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Seems my tailstock wasn't aligned properly, so I decided to see what I could do to remedy that. Found information on how to make a test bar, which I'll make one day, but really didn't see anything there as to how the adjustments are made. The article tells you more about how to find out if it needs alignment then it does about how to go about doing it. Did a quick and dirty attempt at aligning the tailstock this evening and am probably closer then I was before. Would one of you that has some experience with doing this outline a procedure for aligning the tailstock. (Tim Wilhelm) There are several types of adjustments. Most that I have come across are two push screws on on each side of the tail stock. loosen one and screw in the other in the direction that you want the tail stock to move. The Homier I have is different, it has two screws on the back that are just locking screws. It also has one on the bottom of the tail stock that locks it from the bottom. Have not figured out why. I understand the Grizzly 7X10 and 12 has a locking screw on the bottom and none on the end like the Homier. If you have the Homier, lightly loosen the two screws on the tail stock end and lightly tap it in the direction it has to go. My 9X20 has an adjusting screw on each side. I had a deal the other day. It seemed like the tail stock was way off. Could not figure that one out till I found the new 3/8 drill bit I was using had a slight bend in it. Went back to the old one and no more problems. (Tony Spezio) It's a Grizzly 7x12 that only has one adjustment screw on the tailstock, and a cap screw underneath it to tighten it in place. The problem comes because you pretty much have to take the tailstock off to get to the cap screw. I suppose I could get to it from the bottom, but it would be tough. Add to that, when you tighten the tailstock down on to the lathe, it has a tendency to move or rotate. That torque maybe reason enough to modify the attachment to what varmint al shows on his web site. I figure you don't want to align it with the tailstock just setting on the lathe, but instead it needs to be attached as it would be while in operation. It's doable but kind a like going around your "you know what" to scratch your elbow. ;^) (Tim Wilhelm) The easiest way I've found to align a tailstock is to stick a dead center in the tail stock, and also one in the headstock (you may have to remove the chuck to do this). Then, take a real thin feeler gauge, one that's almost paper thin, move the tailstock so that the points of the dead centers are almost touching, secure the tail stock, and hold the feeler gauge between the two points. Advance the tail stock by cranking the hand wheel, until the points touch the feeler gauge. You'll know through immediate feedback, whether the tailstock is in alignment or not. If the feeler gauge twists to the rear, you need to move the tailstock towards the back of the lathe. If it twists towards the front, you need to adjust the tail stock towards the front of the lathe. Repeat until the feeler gauge doesn't move. Once you've aligned the tailstock, scratch a witness mark on the tailstock so that if you ever need to readjust the tailstock, such as turning a taper, you can realign by lining up the witness mark. (Mark Wendt)
This is probably an "old hat" question for most of you people who make your own ferrules and reel seat hardware but it has just raised its ugly head to me and I hope you will take a little pity on me and share your experience with me... Picture this: You have a 3" piece of NS chucked up in your head stock with 2 1/2" sticking out and are attempting to build a male ferrule part. This piece has been drilled to fit over the cane flats. The tail stock is loose on the lathe ways and you slide it up to fit the live center in the drilled end of the ferrule. You then tighten the bolt holding the tail stock to the ways and adjust the live center to be snug in the ferrule opening The next step is to turn the OD down to .250". You do that, making a measurement after each pass of the lathe tool, until you get the turning down to a measurement of about .252". Now you part the ferrule off near the head stock and very carefully measure the newly turned part at several locations along it length. HOLY JUMPIN UP. The stupid thing is .004" smaller at one end than the other. SSSOOO, you take out an expensive 12" piece of brass stock, set it up between centers and begin the task of realigning the tail stock. If you are a little 'slow' and doing this for the first time, it takes most of the day. So, the next day you start building another ferrule and when you make the male part again and measure it "again" you discover that the original problem of .004" still exists. So, you disassemble, clean and oil the tail stock and put the dumb thing back together. Only this time you are forced to get the dial indicator out and put it on the tail stock thimble and zero it and when you (Tightened The Bolt Holding The Tail Stock To The Ways) the dial went from the "0" set to .040". CONCLUSION::: The alignment of this 9x19 Grizzly lathe tail stock is critical to "HOW TIGHT the tail stock hold down ! bolt has been torqued. My Question:: Is there a way to resolve this 'tightening' problem? I would think this might be a problem common to a lot of lathe types. (Don Greife) Brownells sells a set of modified tool maker's buttons that fit between centers so that you can measure the two at the same time. This is a quick way to get rid of tail stock alignment problems. However they are only as good as you mic. You should be able to get within .001 per 12 inch easily. Of course the most accurate way is to turn test pieces between centers. (John Zimny) I've discovered that it helps to be at least as smart as your hammer if you plan to drive a nail. I spent the morning redoing many of the checks on my 9x19 Grizzly that I did yesterday. Last night when I shut the door on the shed I was discouragingly convinced that I could "NEVER" align the tail stock in a "permanent, repeatable and reliable" fashion, because it seemed that the alignment changed every time I moved the location of the tail stock on the ways and had to retighten the hold down bolt. It appeared that the 'new' alignment could be different by as much as .040". WELL, THAT is the part of the hammer I didn't understand. This morning I put a dial indicator on the top of the tail stock quill and loosened and tightened the hold down bolt a number of times looking for movement, well there was 'none'. Then I put the dial indicator on the side of the quill and repeated the process of loosening and tightening the hold down bolt and the movement was < .001". CONCLUSION: Alignment of the tail stock by turning a test bar between centers should provide "good" alignment of the system and I should be able to turn both male and female ferrule parts that "POP" when you pull them apart. While the ferrules I've built do fit together tight and look pretty good (even if I do say so myself) they refuse to "POP" and that's the part of the 'hammer' I'm working on now. I have confidence in the lathe alignment. If you can help me with my "POP" I'd appreciate it. (Don Greife) Talk about a coincidence... On the 7x10 mini lathe list I received an email this morning describing pretty much the same problem you were describing. One of the listers came back with this: For a quickie project, LMS has a plan posted of a tailstock adjuster. The first line of text under the picture of the device (and it's really quite simple to make) goes like this: This tailstock adjuster makes it much easier to adjust the tailstock to center or to adjust it to cut tapers. Maybe this would be the solution to your dilemma. (Mark Wendt) I think that tail stock aligner has some merit and will probably build one for my 9x19. (Don Greife) I think I'm going to make one too. Looks simple enough, and could be made out of aluminum and brass, rather than the steel they use. With aluminum, I can cut out the middle with a hack saw and file to shape. Since I don't own a mill, I look for the easy way...(Mark Wendt) The easy way might be to use a piece of 1/8" plate over two pieces 1/2" square bar. Then all you would have to do is cut to length, drill and hold them all together with a bolt instead of the cap screw. (Tim Wilhelm) I haven't been able to make the males so that they fit like that right out of the lathe. I don't think it is possible except by accident. I have been able to make them so that they have 25 - 50 percent engagement right out of the lathe, but they always need a bit of lapping to get the "pop" fit you are looking for. (Darryl Hayashida)
I recently found my lathe not drilling holes for ferrules straight. Realigning the tail stock didn't fix the problem so I began to check the alignment of the chuck and found it to be pretty straight. Well there was little left to check out except the head stock itself. So, I set a magnetic base dial indicator on the cross slide and checked for both vertical and horizontal alignment. The vertical alignment was dead on but the horizontal was off by 0.009" in 4". At this point, having no idea what to do to correct this mess, I called on the expertise of (your good friend and mine) Tony Spezio who guided me through the process of things that needed to be done to accomplish the head alignment. Thanks Tony, your mentoring and words of encouragement saved me a trip to the Grizzly Maintenance Shop. The following is a summary of the head stock alignment process I went through. Let me preface it by saying that if you own a Grizzly (green) or the Gray one that a quick check of your head stock alignment may well worth the little time spent, considering that I found two head stock bolts and one motor mount bolt very loose. The head stock parts drawing, in the users manual that came with my Grizzly, shows four bolts that hold the head casting in place on the ways bed. It also shows four set screws (two on each side of the casting) which would push against the side of the hold down bolts, to permit alignment of the head casting with the ways. Depending on the version of lathe you may have, there may be four or only two set screws. The two set screw version screws may be found behind the motor mounting bracket. To do the head alignment I used the following tools: Dial indicator with magnetic base, #2 drill index rod (drill rod), hex wrench (metric for set screws), Box end wrenches (metric). Phillips screw driver, pencil and paper. The procedure I used is as follows:
This measurement provides an indication of just how parallel the head stock is with the ways in the horizontal. If this horizontal deviation exceeds spec or your special need, (like ferrule making), you can reduce the error by the following. (leave the dial indicator in place from the last measurement taken)
Also, If you think your chuck/chuck flange alignment is really bad, you might consider using the dial indicator to determine the 'high & low places and mark them on the chuck body and the chuck flange with a permanent marker (use WD40 to remove). You may find that simply rotating the chuck body on the chuck flange 90* that a significant improvement in the alignment may be made and/or a 0.002" shim of scotch tape between the chuck and flange may do the trick. I'd appreciate any comments or corrections anyone may have. (Don Greife)
Just got my Homier 7X12 today, am really satisfied with it, it is real clean. It took two days to clean up my 9X20. (No, the 9X20 did not come from Harbor Freight.) Checked out the runout. It was .0025 out. Removed the chuck and checked the face plate. To my surprise you could barely see the needle move. I was out less than 1/2 a needle width. I felt I did not need to take a face cut. Reinstalled the chuck and still was .0025 out. I tried changing the tension on the hold down nuts. It only changed it .0005. It was still .002 out. Changing the nut tension worked on my 9X20 when I installed a Collet chuck. Finally resorted to an old machinist trick, put a shim of Post It paper between the chuck and face plate. This threw it off .005 in the other direction. I had a Band Aid in the bench, removed the outer wrapper and used a little slip of that. It worked wonders, I am less that .0005 out now. It will stay that way, no reason to play with it any longer. Just a trick if you are having problems getting a chuck to run true. BTW. did not have to make any adjustments on the tail stock. Took a reading at the chuck and at the tail stock. Just about .0005 taper in about 7". Real pleased with the lathe. This little lathe will stay in my rod room, that will keep me from having to go to my other shop to use a lathe. Can't beat the price. (Tony Spezio)
After I removed my Homier lathe head stock to lubricate the gears and to drill the spindle for the Harbor Freight 4 jaw chuck, I remounted the stock 3 jaw chuck after putting everything back together. I found I had .018 runout with the stock 3 jaw chuck. I tried all combinations of remounting and making sure I had no burrs on the mounting surfaces. I was finally able to bring the runout to zero by selective tightening of the 3 chuck mounting nuts. Apparently there must be some flexing of the chuck as the mounting nuts are tightened. Has anyone else experienced this? (Bob McElvain)
I have a Homier 7x12 and seem to be having some excess run out, how do I adjust this? (Tim Stoltz) Just use a magnetic base indicator on the chuck and loosen the three nuts behind the chuck. Don't loosen them too much, just enough so you can tap the chuck with a rubber or brass mallet. I emphasize the word tap. :) Turn the chuck and tap down on the high side until the indicator stays a zero (or whatever you start with) as you turn it. It's easy. (Tony Miller) Where is the run out? Are you getting tapered pieces when you cut straight, or holes drilled that don't center in the work piece? (Mark Wendt) My base indicator is showing run out and when I was making my last ferrule it had a slight taper. (Tim Stoltz) Are you using the tail stock and a dead/live center to stabilize the work piece? You may need to ensure the tail stock is centered on the head stock. Sometimes, in fact most times, the factory setting on the tail stock does is not centered. For a quick and dirty check, what you can do is put a dead center in the tailstock, and a very small drill clamped in the chuck. Slide the tail stock up, tighten it down, and with a thin shim, say a feeler gauge held against the drill bit with the flat side perpendicular to the ways, slowly bring the dead center to the drill. If your tail stock is not centered on the piece, the shim will deflect one way or the other. If the shim deflects towards you, the tail stock will need to be moved to the back side of the lathe. If the shim deflects away from you, the tail stock will need to be adjusted to the front of the lathe. The Homier tail stock makes this kind of a pain in the butt, but to adjust the tail stock, you have to remove it from the lathe. There are three bolts that you have to loosen, two under the crank handle, and one on the bottom of the tail stock. You may have to do this check a number of times to get it lined up dead nuts on. Once you've gotten the tail stock set correctly, make a witness mark across the base and the tail stock upright, so that if you have to offset the tai stock to do an operation, it'll be a piece of cake to get it back to center again. (Mark Wendt)
I've been looking onto the archives and web sites about lathe runout. Doesn't seem to be much info on the subject. Can't find very much info on correcting it either. I got a kick out of your post, Tony, about correcting the runout of the chuck with a piece of wrapper off of a Band-Aid. I was able to eliminate the chuck runout by adjusting it, but sill had runout at the jaws. I used a diamond hone and a lot of time and finally got them to under .001". I was looking in catalogs for chucks (self centering 3 or 4 jaws) and about all of them advertised around .003 tir (total indicator runout). This seemed a bit much, especially for turning ferrules. What is the allowable amount of runout for making a set of ferrules and reel seat hardware? I zeroed the dial indicator at (on a chucked piece of round rod) the jaw with the most positive reading and then polished off a few thousandths off of the jaws reading a negative. It was a hit and miss and if I took off too much, it was start all over again! Is there a formula somewhere to calculate how much to take off and where to take it off? Or is minimal runout just something to live with? (David Dziadosz) There is ever increasing lathe info at www.mini-lathe.com. Varmint Al describes his method of runout adjustment here. I bought a 10 inch length of 1/2" ground rod from McMaster-Carr that I use for measuring and truing the jaws. (Onis Cogburn) I took the chuck off my 7x12 Speedway lathe and the runout went to hell. Before I took it off it was less the .0005, after removal it was more than .005 no matter what I did or how I rotated the chuck position on the flange. Finally I loosened the nuts and tapped the chuck with a nylon hammer while measuring. I easily went back to better than it was originally. I don't think the grinding of the individual jaws is necessary. These are great machines. (Bob McElvain) The only way you can get a chuck to 0 is by using an adjustable chuck. I have a six jaw-Zero Set chuck on my South Bend lathe. You buy it with an adapter plate to fit your lathe and the chuck has six screws around the outside, which you use to move the chuck on the adapter plate. With this chuck and my tailstock adjusted properly, I can hold .0005. That's a half a thousandth. These chucks aren't cheap, though. My chuck with the adapter plate, ran me around $1,000.00 You can pick them up a little cheaper now. There are a few companies making them. You can get them in three jaw or six jaw. (Dave LeClair)
After I got my 7 x 12, I used a dial indicator to check the chuck alignment and it was perfect. I took the lathe apart to remove the heavy grease and I carefully marked the position of the chuck on the hub so I could reassemble and get the same good alignment. Concentricity was off by .008 when I reassembled. I tried other bolt positions with no improvement. I got the alignment back by snugging the bolts, then using the dial indicator on a magnetic stand, tapping the chuck lightly with a nylon hammer, I was able to get perfect alignment. Well, at least as perfect as I can measure with tools from Harbor Freight. The hub and chuck have a self centering flange but it needs a little help. Good luck. (Bob McElvain) Sometimes little nits will get between the face of the faceplate and the area that's been machined away on the chuck to fit onto the faceplate. I had that happen on mine. Even so, on my large chuck, I have to shim it on one side so that I can get it back within tolerances. A nylon, or rubber hammer, however, does make a great "persuader"... (Mark Wendt) It doesn't take much to get a chuck out of alignment. Everything you did was right. In my case on my 7X12, I had the shim one side with a slip of paper from a Band Aid wrapper. On my 9X20, changing the tension on the bolts did the trick. (Tony Spezio)
I know there are other ways to check your lathe for runout, but I just do it the way it works for me. Note, all right or left readings are FACING the indicator First thing is to check the chuck for run out. Put a short length of drill rod (I like 3/8 or 1/2") in the chuck. You only need a couple of inches out beyond the chuck jaws. Set up a dial indicator, set the indicator to zero on the stock and rotate the chuck by hand. This will tell you if the chuck is off. When turning the chuck, if the indicator reads more than .0005 deflection you need to take care of this first. Rotate the chuck by hand till you get the highest deflection. Reset the indicator to zero. Now rotate the chuck slow by hand. If the indicator needle moves to the left of zero that means the stock in the chuck is moving away from you, if to the right of zero, that means the stock is moving closer to you. This can be corrected by a couple of different ways. What you are trying to do here is get the stock so that there is no deflection. If the stock is closer to you ( indicator reading to the right of zero) the stock needs to be moved away from you. That can be done by cocking the chuck. Lots of times cocking the chuck, can be done by just tightening or loosening the chuck attach screw on the opposite side. If you want the stock to move away from you, tighten the screw(s) on the far side of the chuck or back off on the screw(s) on the near side. The tightening or loosening is just a touch. Just a slight bit can make a difference. That is all it took on my 9X20. On my Homier, I shimmed the chuck with a slip of paper from a Band Aid wrapper. The shim will be put between the chuck and face plate to cock the chuck away from you. I hope this is clear enough. A newbie might have to read it slow and visualize each step. When you have the chuck running true, you can set up the tail stock. If you don't have a dial indicator set up, put a tool bit in the tool holder and with the cross slide move it up to the drill rod as you turn the chuck. The tool bit will touch the drill rod at the point nearest you, adjust as above till the tool bit point touches the drill rod even, all the way around. After each try, you should move the tool bit to a new location on the drill rod. Homier does not have positive adjustment screws on the tail stock. This is about the only thing I can find fault with. The tail stock on mine has a locking Allan head screw on the bottom and two slotted set screws on the end. It is impossible to get to the screw on the bottom with the tail stock in place. Here is what I did to line the tail stock up. Removed the tail stock and just snugged the bottom screw, not tight. Put the tail stock back on the lathe and did the same with the two screws on the end of the tail stock. I have been told that some of the later Homiers only have the bottom screw. No real problem, the same way is used to align the tail stock. Put a length of rod or tube about 8" long in the chuck and bring the tail stock up to it. Center drill the rod for the tail stock center. If a tube, use the tail stock dead or live center to hold in place, a rod will do a lot better than the tube. Tighten it all up and take a cut the full length. Take cuts till you get a clean cut the full length. With your caliper, take a reading at the chuck end and at the tail stock end on the rod or tube you are turning. If the reading is larger at the chuck end, that means the tail stock it closest to you. Loosen the lock nut just a bit. With soft mallet, tap the tail stock at the base, away from you. Lock the nut back down. If bigger at the tail stock end, tap it away from you. Tap very light as just a small bit makes a big difference. Take another full cut and check again. Do this till you have the same reading on both ends of the rod. It will take several cuts and taps but you can get it right on the money. When you have the same readings at both ends, Loosen the lock nut and remove the tail stock. Tighten all the lock screws that were just snug. Put the tail stock back on the lathe and check it one more time. It should be right on. Now here is a better way and easier if you want to make a adjusting setup for the tail stock. Go to Little Machine Shop. Click on Projects, click on Tailstock Adjuster. I started making one but have not finished it since I have my tail stock centered. Also print out the Mini Lathe Users Guide. Loads of info on that site. Hope this will help you all get your lathes tuned up. Mine was almost right on out of the box. (Tony Spezio)
I'm driving myself nuts trying to align my lathe. Here is the problem: Turning a 8" long aluminum rod, the rod diameter is off by a couple of thousands end to end. Sounds simple, move the tail stock. I must have more than one thing wrong. If I align the tail stock by putting a center in the head stock and adjust the point of the tail stock so that it spears a business card between the points and doesn't rotate it in any direction, I'm off end to end. Thinking the problem my be in the chuck, I turned a 60° point on a rod, Without removing the point from the chuck and aligning the tail stock point to the new point. I'm off on the other end of the 8" rod. Playing with moving the tail stock so that each end of the 8" rod is the same diameter, not a easy task, when I check to see if the tail stock point lines up with the point at the head stock, it's off. Turning from left to right or right to left I get different results by as much as .003". Thinking the bit may have something to do with all of this, I changed bits & types. Same results. Took the lathe apart and went through all of the adjustments. Went through all the above again. Same unacceptable tolerance error. The only thing I haven't changed is the live center in the tail stock only because I don't have another one. It turns and doesn't flop around and looks OK. Could the problem be in the shaft that comes out of the tail stock that holds the live center? (Don Schneider) After reading all the things you have tried, it sounds like the bed may be twisted. Have you tried centering the head and tail stocks, then adjusting the bed to achieve the same stock diameters at 8 inches? (Ron Grantham) You may be right, because I've had the tail stock adjusted so that either end of the rod would end up fatter. I don't know how to adjust the bed. Another puzzling question, if it is off, how did it happen? I haven't picked up the lathe and thrown it on the floor, not that I haven't thought of it in the last three days trying to correct this problem. I've also had the tail stock adjusted so that the rod is the same on both ends but the live center wouldn't line up with a center in the head stock. That really baffles me... In the past I've made ferrules dead on the money with this lathe. At present I can plane a rod to closer tolerances than this thing will make ferrules. I'm ready to chuck the whole thing and get a real lathe. Anybody need an anchor? Daddy always said "Cheap tools are expensive." I’m having a drink. (Don Schneider) Ron may be right that your spindle is not aligned with your ways. I recently adjusted my lathe and found this web site which has some good information about aligning the lathe. There are couple things that I think work against you when adjusting the lathe that caused me to stop when I got within .002" First, I think there is a little torque created when you tighten down on the tailstock. I bought a replacement tailstock form Micro Mark tightens down with a cam lever to solve that problem. Without some modifications to the tailstock that would allow fine tuning, I think adjusting the tailstock is a little bit of a hit and miss operation. If the taper on your 8" rod is .003" then you need to move the tailstock .0015 one way or the other. How do you measure that? Loosen the set screw, tap lightly with a ball peen and cross your fingers. For me it was adjust and test, adjust and test and so on until I decided I couldn't adjust another time. The other thing to remember is that you are testing your alignment using an 8" test bar. What do you plan to turn that is that long that needs closer tolerances then that? Or is it more likely that you are turning something like a ferrule, more on the order of 1 - 2 inches hanging outside of the chuck jaws and in that case your taper is .001 or less. (Tim Wilhelm) Could be a slight warp in your ways. Also, when you chuck up the piece, and put the center into the stock, how far out is your tailstock quill extended? It to may have a slight bend in it. Chuck up a DTI in your headstock, extend your tailstock quill, and run the DTI around the inside of the quill. (Mark Wendt) Thanks to all that responded for your help. I'm not done yet but thought I'd give you a update. This all started because I jammed a cutoff tool and knocked my lathe out of alignment. I have an excuse but let's just say it was stupid on my part. I used the alignment procedure found here. Well, I now feel comfortable making the adjustments on the HS/Ways alignment. Here is what I've found so far: Measurements taken using a shock rod & drill rod are the same. So, anyone that goes through this, which I hope you don't have to, won't have to buy a drill rod if they can salvage a rod out of a shock absorber. I marked the chuck jaws and rods and took 2 sets of readings 9" apart for vertical/horizontal alignment with the dot on each rods lined up with each chuck jaw. Averaged the measurements and found the HS/Ways alignment error is: Horizontal error @ 9" is .006" to the rear. Vertical error @ 9" is .00325" down. One thing surprising to me, the range of the numbers: Horizontal .006125" to .005875" Vertical .00425" to .002063" These ranges seem large to me. Not sure what this means but when I get this puppy aligned I'm going to mark the chuck/bolts so I put the chuck on the same bolt pattern each time. Any answers/comments? Now for the fun part, fixing it. (Don Schneider) Your range of errors may be due to the inaccuracy of your self-centering 3-jaw chuck. This is common in most lathes, large and small. For exact accuracy, use an independently adjustable four-jaw chuck. When temporarily removing material from a 3-jaw chuck, always mark the piece at the #1 jaw and put it back in the same position. (Ron Grantham)
I was turning some metal for a slide band and noticed something that just didn't seem right! After turning the piece, it still looked like it had a lot of run out. I set up a dial indicator/base. Chuck looked pretty good, but a piece of drill rod several inches from the chuck was pretty far off! Trying to figure out how to adjust it to eliminate the runout, (chuck screws onto the headstock spindle), I decided to true up the jaws with a light grinding, (mainly to see if that was the problem). The grinding wheel touched all three jaws! Then I noticed something that seemed way off base! I didn't have the same amount of runout on each revolution! I marked the high spot on a drill rod several inches from the chuck and set the dial indicator on zero. One full revolution, a reading of negative .005". One more revolution I got a reading of negative .002". After a third revolution, the reading was back to zero. After more testing, the readings bounced all over the place, never the same, but always came back to zero. Sometimes after three revolutions, sometimes after five! The indicator was set up solid. The only thing I can figure out, is maybe, kind of, sort of, could it be, nah it can't be, back to maybe, a flat spot in one of the bearings in the head stock? The balls in the race can rotate at a different rate than the shaft. This is on a new 9X19 Grizz. I have to wait till Monday to to talk to a service tech at Grizzly. Has anyone run into such an odd ball problem? Has anyone changed out the bearings in the headstock of a 9X19/9X20 lathe? Is there a service manual for this lathe? Other than the common "Owner's Manual". I'm beginning to think this lathe should have been painted yellow (lemon) instead of green! (David Dziadosz) Boy, something has to be loose in there. The only problem I had was I had to face off the back side of my 4 jaw chuck to square it up. But I'm sure that (before) I did this, I was getting consistent readings, so this couldn't be your problem? the fact you say that it always comes beck to "0" is also strange. Do you have 2 chucks and are the results the same? (Martin Jensen) Last night, I pulled the spindle out. The parts manual labeled the bearings as "ball bearings". They're actually "tapered roller bearings". So, they can be adjusted like the wheel bearings on an automobile. The wear pattern on the races were different. The inboard bearing race was shiny all the way around. The outboard bearing had more of an uneven wear pattern. Grizz is supposed to call me today. I'll find out more. (David Dziadosz) Last night I pulled the bearings out of the head stock. The inboard bearing had a small rough spot in it. In a so called precision machine, a small rough spot might as well be like the Rocky Mountains! The wear pattern in the outboard bearing race was uneven. I talked to a Grizzly tech today and he agreed that it was the bearings! A new set on the way! The bearings in the lathe are shipped fairly dry, a small amount of rust was on the inboard bearing! Improper load on the bearings probably caused the uneven wear on the outboard race. Hopefully the mystery will be solved in a couple of days. (David Dziadosz) If you check the Yahoo lathe sites you will see that the Chinese lathes are using automotive bearings. Had six things to do to make my Jet 9 x 20" more accurate. Most beneficial was replacing the headstock bearings with new Timkin P-6 (precision). (Jerry Young) Even lower quality bearing won't account for that kind of run out. The run out difference between the best and the worst is only a few tenths. Quite likely the preload on the bearings was not adjusted properly at the factory or the adjusting nut has loosened up. Typically, there is a nut on the spindle which "clamps" the headstock bearings together. There should be a washer with tabs keyed to the shaft so when the nut is adjusted properly, the washer tabs are bent into slots in the nut to keep it from loosening. You could look to see if such a setup exists in your lathe and if the nut has loosened. (Al Baldauski)
I hadn't made a ferrule in about a year, when I first figured out how to make them I made quite a few sets in the sizes I use the most, in fact I still have three 13/64ths Duronze ferrules left, but now I need a couple sizes in aluminum for the 6’ 4 piece backpacking rod I am making. In a moment of stupidity I ran the carriage on power feed into the tailstock hard enough to stop the lathe before I could turn off the switch. The power feed makes a new rattling sound, but it still works smoothly. But, in checking to see if the tailstock is still aligned I turned 4 inches of steel rod down 0.004 inches with a live center and checked to see if everything was still straight - and it wasn't. The spindle side was 0.003 larger than the tailstock side. I ran the cutting tool back and forth four times to make sure no chips were coming off, the rod was as true as the lathe was ever going to make it, and checked again. The spindle side was still 0.003 larger than the tailstock side. I have a Homier mini-lathe and on it the tailstock is adjusted by an allen head screw on the bottom, accessed from underneath the tailstock, and two set screws on the top of the base. So I have to take the tailstock off, loosen the hex bolt, put it back on, loosen the two set screws, loosen the main hold down nut, tap on the tailstock to get it to infinitesimally move in the right direction - in this case away from the cutting tool, tighten the set screws, tighten the hold down nut, turn the steel rod down another 0.004, running the cutting tool back and forth several times until no more chips come off, measure the diameter in several places down the length of the rod. It wasn't straight yet, so do the whole thing over again - you get the idea. Four hours later of doing this over and over again I can cut the rod as straight as I could before I ran the carriage in to the tailstock. Moral of this story - Don't run the carriage under power feed into your tailstock! It would be nice if there were some power cutoff switch before the carriage hit the tailstock. (Darryl Hayashida) I recently went through the same dilemma of aligning the tail stock. I made the following modification and it makes life easier. Also moved the TS adjusting locking bolt from underneath to where you can get at it with a allen wrench from above with the TS mounted. Requires drilling the present threaded hole so a 1/4 x 20 x 1 1/4 cap bolt will pass through from the top and through the slotted hole below. Use a 1/4 x 20 hex nut and washer in the slot. If you don't have a cam lock TS you can still get a wrench on the main lock nut. With these modifications and setting up a DTI on a mag base you can measure the movement between the top & bottom of the TS, forward and back, to less than .0005" When I jammed my lathe I also checked/aligned the Head Stock to the Ways. That a lot of fun ! :>) If you want to check it out here. Think mine was off from the factory and the miss alignment was not caused by the jam. Here is the order I followed: 1. Got rid of the rubber feet and bolted the lathe to a piece of 5" x 1/4 x 28" "C" channel. 2. Did the Head Stock to Ways alignment. 3. Made the modifications to the TS. 4. Align the TS. (Don Schneider) The tailstock adjuster looks like it would do a good job, but I don't usually change the adjustment. I'm not sure making and installing it would be worth it. Hopefully I won't knock my tailstock out of line again. I did just order the tailstock cam lock from littlemachineshop.com. I got really tired of having to move the compound tool rest out of the way every time to tighten and loosen the tailstock while I was adjusting it, and and maybe if I am quick enough I can unlock the tailstock before any damage is done if I ever do this again. (Darryl Hayashida) I like the Tailstock camlock but it does sometime get in the way of the compound when you need to get in tight. As when you are cutting ferrule stations ! It is then necessary to run the TS dead center pretty far out to provide enough clearance. The reason I chose to get the littlemachineshop.com design is the handle goes behind the tailstock and doesn't appear to have anything that would interfere any more than the stock setup. Here is a picture of the cam lock. The picture of the installed kit is near the bottom of the page. (Larry Swearingen) I received the tailstock cam lock from UPS yesterday and installed it. Installing the cam lock involves drilling the casting with a 1/2 inch drill. Fortunately I do have a 1/2 inch drill bit and a 1/2 inch power drill. One word of caution though, installing the way that I did - leaving the tailstock on the lathe and marking where it needed to be drilled with a hammer and center punch knocks the alignment off again. So I spent another couple of hours aligning the tailstock again. The tailstock adjustment mod is looking better and better, but hopefully the tailstock won't go off again - knock on wood. The cam lock is great! As many others on this list has been telling me. Being able to move the tailstock out of the way in a second and consequently being able to crank the compound rest out of the way is a huge help in many lathe operations. The cam lock also allows me to conveniently move the tailstock closer up to the work when drilling and reaming, making the setup more rigid and a little more precise. It's one of those "How did I ever do without it" things. (Darryl Hayashida) You might want to remove the gear cover and check the gears out carefully. I once ran the saddle into the end of the lead screw, and it cracked the gear on the lead screw. They're just plastic, and they can't take much abuse. That could be the source of the rattling sound. In my case, the lead screw still turned, but the crack was large enough that there was a gap in the teeth of the gear, effectively turning the 80 tooth gear into an 81 or 82. (Robert Kope) Since you put the Tail Stock OUT of adjustment by force I would have suggested putting it back IN adjustment by the judicious use of force. How 'bout a little tapping with a lead or brass hammer in the correct direction. I bet it would work easier and with more accuracy than trying the standard procedure of taking the TS off the ways and making the adjustment, then remounting the TS. After all you are only talking about a total movement of .002" in the tailstock. I've got a Grizzly version of the same lathe and that's how I fine tuned mine after the frustration of the "Standard Procedure." (Larry Swearingen)
I've discovered that my lathe (three year-old Sherline 4400) is out of true. I put a drill rod in preparing to fit a ferrule and discovered that there's a slight wobble when the lathe rotates. To double-check I brought the tool-holder up to the face of the three-jaw chuck and as it rotates it comes in and out of contact with it. Can this be tapped back into place with a mallet or must some other alchemy be performed? (Henry Mitchell) If I understand what you're saying, the 3 jaw chuck wobbles off axis. Unscrew the chuck from the head spindle, check the threads on both. Check the spring clamp on the back of the chuck, check the two faces of the chuck for easy turning & even mating or look to see if the screw threads inside might be throwing it off. If you have a magnetic base stand with a indicator gauge it will help check all the parts. Also check your lathe head adjustment to see if it's true. (Chad Wigham) I hate to say this but it may be the problem. Have you turned anything that might of hung up. I had this happen on a small lathe I had. Was cutting off a piece stock with a cutoff tool and it hung up. The bit went under the metal. After I cleared the jamb, the chuck would not run true. I had bent the spindle just behind the threads and had to replace it. I tried to get it back true with a lever and a rubber mallet. Never got it true enough to satisfy me. I was lucky enough to get a new spindle. Replaced it and sold the lathe, then upgraded to a larger lathe. (Tony Spezio) Tony is right, as he so often is. What probably caused this was starting the lathe when the rods used to tighten the chuck were still in it. Remembering this I took the coward's way out and called Sherline. They say it could be either the spindle or the chuck, to send them the headstock and that they thought send it back the day they receive it. In full realization of my own mechanical incompetence, it has already been packaged. (Henry Mitchell) What probably caused this was starting the lathe when the rods used to tighten the chuck were still in it. That's a no-no! (Neil Savage) Make sure the headstock locking screw is tight. If it's not locked in place the headstock will vibrate. It will appear that the spindle is not turning true. It's also possible that the headstock key is not seated properly making it difficult to lock. Remove the headstock and clean the key and the groove that it rests in. (David Bolin)
I have a 7x12 mini lathe and after a year decided the reason my ferrules seem to kick left or right after mounting is because I'm cutting the station on the lathe and maybe the chuck is not true (Thanks Tony). So today I mounted my dial indicator on the tool holder, chucked up a 9" length of 3/8" drill rod and sure enough at about 6" out there is a .005" run out. Whether or not this is the problem with my ferrules is still up for debate, but for sure the run out is unacceptable. Now to the question - how the heck do I true the chuck. My initial thought is that something somewhere needs to be shimmed, but since I have never set up a machine lathe before I want to make sure that I don't make things worse. I have no doubt that many of you have faced this same dilemma at some point and hope you would be willing to share the "truing" procedure with me. (Tom Key) P.S. If you're wondering why it took me a year to realize the chuck wasn't running true it's because I just build my first 3 pc. 2 tip blank and it's not as easy to work around the ferrule issue by picking the most accurate flat. In my case it just took the thickness of a "Band Aid Paper Wrapper" between the chuck and mounting plate. Find the side that the test rod is reading the highest deflection, that means that the chuck has to be moved away from the mounting plate. Loosen the mounting nuts on the studs holding the chuck. Slip a paper shim between the plate and chuck at that point. Tighten the nuts and check it out again. It don't take much at the chuck to make a difference at 6". Do this till there is no deflection. (Tony Spezio) Just to be sure we are on the same page here, do you mean that the indicator needle is oscillating by .005, or that it is a consistent .005 different from the reading where the rod exits the headstock? If it's oscillating, Tony's advice is the cure, but I would first make sure it's not the rod being slightly bent. Mark the high point of the oscillation on the rod, then rotate the bar 180° within the chuck. If the marked side is still the high point, it's the rod, not the chuck. If the reading is a consistent .005 off, then it's the headstock itself that is out of line. When turning ferrule stations, make sure the section itself is dead straight, and be sure the section is centered where it exits the back of the headstock hole. I use a bored out plug which just fits in the headstock hole, and the blank is padded up with masking tape until it is snug in the plug. (Tom Smithwick) Good point Tom, I had assumed that he meant the rod was oscillating. (Tony Spezio) Are you sure the piece of drill rod was STRAIGHT? It wouldn't take much to show a TIR of .005 at 6" out of the chuck jaws. Besides that if your chuck reads a TIR of .003 that's pretty good for a 3 jaw chuck. I bet your blank doesn't measure that close across 3 flats. When you cut your ferrule station you want to keep the blank as close to the chuck as you can get it and still cut bamboo. You may also need to shim a flat to get the blank running closer assuming your blank doesn't measure within a thousandth across all three flats. 'Course that's NEVER happened to me! {:>) (Larry Swearingen) Another thing to look at, is the fit truly a snug fit between the bamboo and the ferrule? The slightest “give” may cock the ferrule while drying, Ask how I know this. (Ren Monllor) And yet another issue is if you wrap tape around the blank to protect it from the chuck jaws, be sure you have the same number of layers under each jaw. Actually, fit-wise it's probably best to use only one wrap, but then you take a chance on marring the blank. I try to get the overlap on a flat that falls between the jaws. (Neil Savage)
I need some advice. I have a cool little Unimat lathe I intend to use in making ferrules and other small parts, but I'm having trouble getting it to run true. The spindle itself has less than .0005" run out. With the 3-jaw chuck in place, I can't get it to less than about .003" of run out. Someone suggested that I gently remove material from first one jaw, then another, of the chuck until it runs true. After considering doing so and examining the chuck carefully, it appears that has already been done. And it seems that at least two of the jaws have had more material removed at the rear than at the front. I could be wrong, but when a piece of drill rod is lightly clamped in the jaws only the rear of the jaw is touching the material. That allows the drill rod to wiggle around slightly at the front of the jaws. Any suggestions? Should I try to correct the problem? Should I buy a new 3 jaw chuck? Know where I can find a good one? (Harry Boyd) I’m not a machinist but I would think that if you mounted some sort of drill or round file in the tailstock and opened the jaws to just make contact, start the lathe, adjust the jaws a bit tighter etc you could get all the jaw surfaces level to one another. Just a thought, no experience with this procedure. (Mike Monsos) I think that purchasing a new 3-jaw chuck would be the best way to go. Why not go to "Google" and put in "Unimat Lathes" and watch a lot of suggested possibilities and information. Just my suggestions. (Frank Paul) I had somewhat the same problem with a grizzly. Truing the backing plate solved the problem. Previously ground jaws could be another problem. And I am surely your worst source of advise for machining problems. (Larry Tucker) I have one of these things somewhere in my garage ... First things first ... Before you start cutting, lets explore some of the symptoms deeper. Are you sure the jaws have been installed in the proper order? How are you determining that the chuck is not true? Have you tried rotating the chuck 1/3 turn on the back plate to see if the run out changes? First, if the chuck has soft jaws, all you need to do is find a known true circle piece of metal, of about the size of the diameter you wish to chuck (I use an old shaft from a shock absorber). If you can't find one, you can turn one with the jaws you have, just locate the jaws on the turned part in the jaws far enough in from the face of the jaws, so you have room to turn a "step" in the soft jaws deep enough for you to chuck on to the piece you need to have true. The piece you use to chuck in the jaws for trueing, is called a "BORING RING". After the step is cut, close to the diameter of the part you need to have run true, just remove the "boring ring", and chuck up your part. It will now run true, if it is true to start with. If your jaws on the chuck are hard, you will not be able to cut a step in the jaws with a tool bit, even if it is a carbide bit. In this case you will have to mount a grinding machine to your tool post, or some other method, so as to be able to move the grinder in or out, or up and down. Depending on how much you have to take in order to true the jaws, a Dremel Rotary Tool with a fairly hard stone in it, should work just fine. Given that you properly have done this correctly ... There is help here ... Here is a Yahoo Unimat discussion group that can also offer advise. UNIMAT Users Group TRUING A THREE OR FOUR JAW SELF CENTERING CHUCK The jaws that are more suitable for use with non ferrous, soft materials like brass, aluminum, plastics, and wood, are called soft jaws and are made of aluminum, as hardened steel jaws, unless padding is used to protect the work will dig and mar the work surface especially when a piece is reversed and gripped around a newly machined surface. The soft jaws as usually furnished are in an unmachined state but is not as bad as it sounds. If you try to use them to hold material as they are, you will find that the inner bearing surfaces may hold the work slightly off center and have a pronounced runout. The inner griping surfaces of the chuck jaws need to be lightly machined in a boring type process to bring them all to not only a concentric condition but also perpendicular to the chuck and parallel to the lathe axis. Open the chuck about mid way and insert a very thin steel washer about an inch in diameter into the opening between the jaws and while pushing it firmly against the back of the chuck face, tighten the jaws. This will tension the jaws outward the same way as they would be when they are gripping a piece of stock. With a boring bar and a medium to slow speed of the spindle, you should begin to take light cuts along the inside surfaces of the check jaws. Check each jaw after every pass to see how the work is progressing and quit as soon as three jaw's griping surfaces are evenly machined along their whole length. Doing it this way will insure that the jaws will hold a workpiece as concentric as possible for the type of chuck it is. The inner surface of the newly machined jaws can be left smooth or it could have a couple of little grooves cut into them for better gripping power. The runout can measured by gripping a short piece round 1/2" drill rod and taking a dial indicator reading from the surface of the rod while watching the indicator needle for any fluctuations as you hand turn the chuck. It should be well within .001" to .0005" although depending of the quality of the scrolling mechanism, it may be less. Because the jaws are relatively soft, they will not withstand excessive abuse and may have to have its griping surfaces lightly machined every once in a while as a matter of maintenance to keep them in tune. The blank set of jaws for the TAIG chucks are very low cost and several sets can be machined for special purpose jobs without much in they way of expense. (Ron Hossack) With a few hours of patient tinkering, I got it pretty close. What I determined was that a previous owner had filed or ground the jaws in such a way that they were larger at the front end than the spindle end. I carefully filed them back to "square" with the threaded side. Then using drill rod and an indicator I determined which jaw was highest and lowest. Next step was to remove the chuck and the offending jaws. To compensate I would make two or three light passes with a #4 Grobet file on the offending jaw. Check for squareness again and reassemble. After 10-12 tried, I got things very close. With the dial indicator at "0" the needle barely wiggles when the chuck is turned. Run out on the chuck is now very close to the same as the spindle itself. The Unimat lathe chuck screws on to a threaded spindle, so there is no back plate. Each jaw is marked, as is its place in the chuck. I knew the chuck itself was out because a dial indicator on the spindle ran within .0005" of true, but a DI on drill stock held in the jaws were out by .003" or so. The jaws are plenty hard, and I was hesitant to mount a Dremel tool or a grinding point in the tailstock, as I had no way to know whether the tailstock itself was true. Never thought to mount it in the tool post. Could have done that somehow and accomplished the same thing I did with a file, albeit perhaps quicker. Thanks again for all the help guys. Another dilemma solved. That's the great thing about this list -- friends helping friends. (Harry Boyd) Is this a self centering chuck? If so, you may never get is close enough for ferrule work unless you use a very good collet set like some had suggested. I have a small Taig lathe, and tried a 3 jaw with collets, but didn’t want to spend the money to get all the collet sizes I needed, and I also found that the collets had trouble holding the bar stock when center drilling. I went with an independent 4 jaw set and that was the answer for me. Takes more time to set up, but I can get it to 0 play each time. Also, using a center pin from the tail stock when cutting will help keep the bar stock running true. (Louis DeVos) If you can't get the jaws true and want to try new jaws they are relatively inexpensive @ $8.40 plus other goodies for your lathe. Visit eBay. (Ron Hossack) If you're going to make ferrules with it, ditch the three jaw and get a 4 jaw chuck. You'll never get a reliable, true running 3 jaw at all diameters. You can grind the jaws, but they'll only be accurate at the diameter you've ground. Nature of the three jaw chuck beast. I've seen other three jaws with much worse runout. (Mark Wendt) Why then, when you turn a piece of metal, it seems to be perfect round and bored center. Then if you have to re-chuck the piece, you'll never get it to run true! And I'm guessing you'll have to re-chuck it to turn a set of ferrules. I'm also guessing that is why the male slide is turned a bit over sized and then lapped to fit. I've practiced making ferrules that turned out pretty darn good using a three jaw chuck. (David Dziadosz) If it is a quality name brand chuck, you can buy replacement jaws. A machine shop can grind your jaws for you - about $150.00 My Opinion- With the possible exception of cut off work (Parting) 3 jaw chucks have no place in ferrule making. Even the best 3 jaw will still be 3-4 times less accurate, with no repeatability, than a collet setup. What you want is some sort of draw in collet setup, with a few collet stops. If your lathe spindle can't accommodate a draw in collet directly, Bison makes a small version of their 5C collet chuck designed for smaller lathes. (Dave Kenney) About the only way to fix the runout in the chuck is to grind the jaws ----- BUT ----- in most cases it will only be trued at the diameter it is ground at, and will show runout at other sizes. You can try and shim the the work piece to run true, but pretty hard to do with something small as a ferrule in a small Lathe like a Unimat. (James Dempsey)
Does anyone have a easy method of aligning a lathe headstock and tailstock? I know about turning a long bar and measuring each end. I'm looking for a quick and dirty method that works, if possible. (Tom Smithwick) I would be interested in this too. I wonder whether you couldn't turn a snug fitting male and a female part, mount one in the tailstock and the other in the headstock, loosen the tailstock adjustments, slide the tailstock so that the parts are coupled, lock the tailstock to the ways and then tighten the adjustments? (Steve Dugmore) If you have a DTI, mount it in the head stock (preferably in a collet, or the very least a 4 jaw chuck) and probe the opening of the tail stock with it, slowly rotating the DTI around the inner circumference of the tail stock. (Mark Wendt) Place a live center in each and line up the centers. (Jim Lowe) Jim's answer agrees with everything I have ever read in the popular U.S, English, and Australian literature on lathes and turning. The only difference is that I don't recall a live center being specified; just a "center," as a dead center should work just as well as a live center. You just need a finite point in both the headstock and the tailstock, and if the points don't meet, you need to adjust the tailstock until they do. (Frank Schlicht) Did that just yesterday with my lathe and managed to get the tailstock with .0005" of dead on. That's as close as I can measure. (Harry Boyd) Here's a pretty good pdf file on this ... Rollie's Dad's Lathe alignment. (Ron Hossack) That method will get you close, but it really depends on the condition of the points on the centers, much like the points on our depth gauges. How many of you fully trust the point on your DG to set 0.000" every time... ;-) (Mark Wendt) Now I'm not a machinist but I do get to play one via email. For my Wood lathe (MT2 HS & TS) I have a set I use. A 60º point on the male and a 60º cup on the Female. Put them in the HS & TS and slide together and adjust until they are seated. Why wouldn't something like this work for a metal lathe to simplify alignment? On mine I'd need a MT3 for the HS and a MT2 for the TS. (Ron Hossack) Sure, if just like your depth gauge, you can guarantee that the points on your centers are accurate. Remember, you aren't holding the part with the point, you are holding the part with the sides of the cone, just like your DG. (Mark Wendt) The dead center to dead center is a good basic method. Similar to setting your cutting tool to center with a feeler gage. use a leaf from a sacrificial set of feeler gages, or a small steel rule. Pin it between the points of the centers gently. If it stays perfectly vertical and square, the points are in alignment. If it hangs at an angle or twists side to side, the points are not in alignment. If alignment is off, the Rollie's Dad's method mentioned is good. Another good source of info is here. The headstock rarely needs alignment, usually the tailstock, gibs, or operator needs tweaking... (Chuck Pickering) The dead center to dead center is a good basic method. I can foresee a possible complication where the points align dead on but the axis of the tailstock is off. This may be resolved by aligning the points when the shaft of the tailstock is fully extended as well as fully retracted.... may involve toing and froing to get it right (Steve Dugmore) I went down to our toolroom and asked the toolmakers. I was told the following for the toolroom lathes...Hardinge's etc.. Obviously the headstock is as is. So, chuck up a piece of round stock that's truly "round" in a collet. Using the tailstock, center drill a hole and using a live center chuck it up from the rear. Use an indicator close to the tailstock to align the tailstock via the gib screws on the that tailstock. This will get you movement to/fro, not up/down obviously. That's all you need. You should be able to align to "dead nuts"! Hope this helps. I'm NOT a machinist. (Jeremy Gubbins) One way to do this is put a dead center in the head or some other point that is true and a dead center in the tail, bring them both together with a razor blade in the middle. If you are lined up, the blade will be vertical and horizontal. (Steve Kiley) That will get you in the ball park, but it won't get you dead nuts on. (Mark Wendt) That's pretty much what I've done in the past, and it will get you close enough for Government work, but what I'm trying to do is get it dead nuts on, so I can turn male ferrules with no taper at all. I was thinking of mounting an indicator on a faceplate or headstock chuck with the point directed inward. Then mounting a drill rod in the tailstock chuck, so that the indicator point contacted it and turning the lathe by hand. The only problem with that is it's only as good as the tailstock chuck. If all else fails, I can always turn the rod... I'll have to get Harry to come over and calibrate my eyeballs. (Tom Smithwick) Brownell's sells some "lathe buttons" for this purpose. I don't know if they would work better than any of the other solutions suggested or not. FWIW (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) If you're really wanting it to get dead nuts on, the DTI chucked up in a collet or 4 jaw chuck is the only way to go. (Mark Wendt) If you want it “dead nuts on” what you describe in your post will get you “dead nuts on”. There are no shortcuts…. (Ren Monllor) There are no shortcuts…. I guess so. I did use the turn and tweak method and got to the point where there's only going to be .0001 to .0002 taper in a ferrule slide. That's probably about as good as I should expect from a 1930's era Atlas, and that much error can be cleaned up with a jeweler's file. Thanks to all who replied, It's interesting how much there is to this stuff when you start looking closely. (Tom Smithwick) Thanks for bringing up this discussion, I just got a new Jet 9 x 20 an could not figure out why I had a .002" taper in my male ferrules. I checked and it was off. (Don Green) Another factor to consider ---- if you have it all aligned and still have problems look to the tailstock height. The import lathes are bad in this respect, you may need to shim, or scrape the bottom of tailstock. (James Dempsey) Tail stock height won't usually cause a taper though. Tapers are caused by the tail stock being offset to one side or the other. The geometry of the cutting tool negates the offset in the vertical. (Mark Wendt)
I'm trying to measure run-out on a tiny little collet chuck. To do so I need to gauge right at the chuck and also about 1.5" beyond the chuck. Every piece of drill rod I check has enough bend in it to throw the measurements off. The same is true for actual drill bits. I tried using 1/4" dowel pins, but they are too short. What I'm looking for is something about 1/4" in diameter that's approx. 3" long, and truly straight. I know I could order some gauge pins, but thought some of you might have a good idea about something I could find locally. (Harry Boyd) I don't know what you could use that would be truly straight but a little math could solve the problem using the drill rod you have. 1. chuck up your test piece and find and mark the point of max indicator reading. Record this reading and readings at 90-degree rotation intervals. 2. Loosen the chuck, rotate the test piece 90 degrees, tighten the chuck, and repeat the readings. 3. You can now subtract out the error due to a bent piece and the residual should be the chuck run out. The idea here is that the error due to the bend will change position relative to the chuck while the chuck run out error will remain in the same quadrant. As a double check you could repeat the process but this time hold the piece in the same position then loosen and rotate the chuck (spindle) 90 degrees and retighten. If it is chuck run out, the error should move to a different quadrant of the test piece. I hope this at least gives you another way to think about the problem. (Rick Hodges) I talked with my bro-in law who has been a Tool maker for eons and he reminded me of something I should've thought of myself. Tim said to get yourself a "drill blank"! They are centerless ground, harder than heck, as straight as anything, can be had in a supply house individually and are relatively inexpensive. This, coming from a precision toolmaker who has drilled holes as small as "0.003 dia. and still has a few drill bits in hand in case anyone calls him a B.S.'er! He's done lots of precision stuff on the grinders for the military contracts so I'll have to say I trust his word Harry. (Jeremy Gubbins)
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