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Rule

As some of you guys know, I have been painstakingly getting my mill up and running. I figure that with this calculation, I am running at about 5800 rpm. The motor is 1 HP at 1750 rpm, the motor pulley wheel is 10", and the spindles pulley wheel is 3". I have stripped most of the original pulleys and the old "vibrating" motor, and this now seems to be cutting much better. Could someone who knows the formula tell me if I am indeed running in that ball park? I think 5700 or so is right where I want to be. Still a long way to go.

I have to say, if you have $400 or 500 to experiment with, you could pretty easily get a mill running for cutting tapered strips. Man, it seems way easier that making planing forms. Get a $200 Baldor (or a $100 Woodtek) or other good motor, motor mounts, get some pulleys and belts, pillow blocks and a 1" keyed shaft, some aluminum angle, bolts, a metal tool stand, a big scrap flat piece of steel for table top, some aluminum and Delrin (or plastic) to make some hold downs, some micarta or fiber board for templates, a few router table kinda of adjustable handles for up/down  adjustment, a few power cords, outlet, a manual motor switch, some Plexiglas for a vacuum hood, a dial indicator, etc....(IMHO) With a drill press, and a lathe, a 1/4 " tap, you could make a great rougher, and maybe even cut strips to final dimension if you could get vibrations minimized and a reproducible height adjustment.  It is amazing what you can get from McMaster-Carr or MSC.

Yeah, so I said I was in the need to break some stuff the other day, but this is now getting to be pretty fun.  (Bob Maulucci)

    Good job.  Mills are fun, aren't they?

    Here's what I use: Five inch pulley divided by three inch pulley equals 1.666.   Now  multiply  1.666  times  3450  and  you  get 5,749.9997, or 5750 rpm -- pretty standard for 3 inch or 2.75 inch cutters.  It is what Dickerson used for both size cutters, for example.  Ten inch pulley divided  by  three  inch  pulley  equals 3.333.  Multiply your 1725 motor by 3.333 and you have the same 5,750 rpm. 

    Remember, rpm's are not what are important.  What you need to know is surface speed of the cutters.  Take a 2.75 inch diameter cutter and multiply that diameter by pi, or 3.1416  and  you  get 8.64.  Multiply 8.64 by 5750 and you get 49,677 inches per minute of cutter teeth travel.   Divide  by  twelve  and  you  get 4,140 feet per minute.  Charlie Jenkins, for example, uses two inch cutters at about 9000 rpm.  Do the math and you realize that he gets 4,712 feet per minute.  Now here  is another variable -- how many teeth you have and how many individual tooth bites or cuts per  second  or  minute.  That is important too -- very important.  Then you have your relief angles behind the cutter faces and lots more stuff.   (Chris Lucker)

      Does it really have to be that complicated?? You're beginning to sound like Garrison, LOL. Can't I just put an X diameter pulley on the shaft and a Y diameter on the motor and if it cuts good call it a done deal? I gotta go get some aspirin.  (John Channer)

        I wasn't trying to make it complicated, just trying to make the pulley choice easier so you can eliminate much of the trial and error.  The feet per minute for the cutters IS important, in fact it is what is really important.  And the  cuts per  second or per minute is important -- along with relief behind the cutters -- for clean cuts.  Some folks out there claim that they cannot get clean cuts with a mill.  They should take another look at their cuts per second (how many teeth/rpm/diameter variables) and the relief behind the cutter faces. 

        Remember, they make different table saw blades for different materials and different tooth angles for different cuts -- ripping, cross grain etc.  Same thing about milling machines for bamboo.  It just so happens that we bamboo guys get pretty lucky with the cheap High Speed Steel 2.75 inch cutters with way too many teeth designed to machine metal.  We get even better results with custom carbide cutters with better relief angles and fewer teeth.  Although, I am still undecided about the value of carbide.  I like how sharp HSS gets.  Carbide cannot be made as sharp as HSS, although carbide stays sharper longer -- at least that's what my tool sharpener tells me.

        I am talking about finish mills, by the way.  You have lots more leeway with rough mills.  And don't get me wrong about finish mills -- you have lots of leeway with them too.  God knows I am not the best machinist and the majority of my stuff works.  (Chris (the trial and error method) Lucker)

          Just shows to go ya how far dumb luck will take you. I got the HSS cutters, domestic, not the imports, and hooked everything up to the 3450 rpm motor that used to be on my table saw, 2.5" pulley on the motor and 3" on the shaft and everything seems to work just fine. I got about 12 rods worth of strips out of the first pair, including cutting the templates. The main thing that has improved the quality of my cuts in having a full length template and a rack and pinion feed. I just feed by turning a crank, but it is much smoother and no burns like when I was pulling them thru by hand and just cutting a straight triangle. Just got my shim stock for making individual patterns for each taper, time will tell if this contraption can cut a finished strip.  (John Channer)

Rule

I thought I'd give you guys an update as to how I am coming along with my mill. First let me say this-if it winds up working, I plan on borrowing my friends digital camera and taking many pictures and forwarding them to Todd for his Tips site. I have had many pics sent to me by a few guys on the list and I found them very helpful so I figured I'd return the favor.

I have acquired most of the big parts- 1 HP 3450 Motor, 5" pulley, heavy duty high speed Mooradian shaper spindle w/1" threaded arbor and 3" drive pulley, 6' of linear bearing with 4 pillow blocks, 6' rack and pinion, and a gear motor with variable speed. The only thing left is the metal, Lexan for dust hood, electrical switches and the like, and, perhaps the biggest hurdle, something to raise and lower the cutter spindle (it probably weighs 35 pounds). I would like to find some sort of over sized compound slide that could be bolted to an angle plate and hence raise/lower the cutter head. Any thoughts?

If you look over the list of ingredients so far it will probably become evident that it's going to be similar to a Dickerson Mill with the two differences mainly being a linear bearing instead of lapped surfaces and the bed will not move.

Thanks to everyone that got me this far and I thank you for your patience with my musings to this point. I suppose I do share this with you in part to stimulate some conversation and hopefully jar loose an idea I may have overlooked. Selfish I know, but I promise to impart anything I learn along the way to all of you here.  (Eamon Lee)

    Look at adapting a Palmgren or South Bend or Logan or whatever milling attachment for a lathe.  Or, the other way around, you can look at using a Micro Fence to raise or lower the bed and keep the spindle fixed.  (Chris Lucker)

    I have just built a rotating base for the Palmgren. Now have adjustable planes for height and squareness to the cutter.  It was the best solution I could come up with.  Still isn't like owning a Bridgeport but it's sturdy enough to handle most small work.  (Jerry Young)

Rule

I am building a roughing mill similar to the Whitehead/Bellinger design including the direct drive cutter setup. I am basing my design solely on pictures in catalogs and books.

I can't seem to find an arbor sleeve that will accept the 1" ID cutters I have. I can turn one on my lathe, but would trust the manufacturing of a pro to my hacking.  Where does on buy this unit?

Also, I have a 1/2 horse 3450 Leeson I picked up from a friend. It's not capacitor start. Will this cut the mustard or should I forgo trying to make this work and just get a 1 horse 3450 cap. start?

Finally, if it turns out I turn my own arbor sleeve, which direction should I thread the end that the lock nut goes on to lock the cutters in? In the direction of the motor rotation or opposite it? I plan on staying away from climb cutting if it makes a difference.

For now that's it. I have an idea for a finish mill but I still need a few more parts. I think it's going to be solid. I plan on making all of my efforts public if something I make works. If it doesn't, well, I'll make that public too. I never learn anything by doing it right the first time!  (Eamon Lee)

    The shaft should be threaded so the cutter tightens when it is under load -- check your power saw.  If rotation is clockwise as viewed from the nut end, it should be a left hand thread.  Otherwise there is a good chance of the cutter coming loose, and that ain't good!

    As to the motor, I have no personal experience, but I'm cheap so I would try the one you have and think about a bigger one if it didn't work.   If you used a belt drive the change wouldn't be very difficult if necessary.  (Neil Savage)

    If you are using the double angle cutters. I have spindles that fit a 1/2" shaft. You saw the rough miller that I was running at the Catskill gathering.  I can send you plans for that unit.  (Hal Bacon)

Rule

I thought I would share this with you guys as I go along so here it goes.

I am almost done making my carriage. It's a 6' piece of 2"x1/2" 6061 aluminum. Two 36" THK 20 mm linear rails are mounted end to end on the bottom along the center. On the top of the carriage nearest the user is a 6' long 1/2"x1/2" 6061 aluminum bar drilled and tapped to accept a pair of push/pull 1/4-20 bolts on 2.5" centers (picture the handmill taper setting assembly.) There are holes drilled and tapped to accept a 1/2"x 1" pattern (material undecided at this point.) This is backed by a 1"x1"x1/8" a 6061 sharp 90* angle to which the tapered pattern, once milled, will be bolted on 5" horizontal centers (picture Dickerson/Bellinger taper set ups.)  Behind this  is the 1/2"x 1/2"x6' rack for linear actuation. This is bolted from underneath on 5" centers. The carriage will ride on 4 bearing blocks, spaced evenly over 18", that are bolted on a 1/2" 6061 plate which will as the base for the other components. If you are not familiar with linear bearings, go to eBay and search linear bearings and look at the pictures. I am technically using them upside down.

I decided to go with an RT Gilman dovetail slide for the up/down motion of the cutter spindle. I'm glad I got it. It's BEAUTIFUL!!! I am going to have a machinist fabricate a pair of positioning brackets to hold the spindle in line. These will be mounted on a 6"x6"x1/2" steel plate and the plate will be mounted to the dovetail slide. Finally the slide will be mounted to a piece of 8"x8"x1/2" ground angle plate. I chose to go with the machinist in order to make sure it's square, balanced, etc...

After that, I have to get a table to mount this thing on and settle on some hold downs, dust collection, and some sort of bearing to take up the carriage overhang.

This is a lot of fun! I look forward to getting it up and running. It's been a fantastic learning process in varied regards and as I said before I look forward to passing along the whole experience. To those who have helped so far I cannot thank you enough. To those who call me a "toy maker" and "lacking commitment to making good rods," well, thank you too! I suppose it helps me better scrutinize the process. However, given the far more important things in my life such as family, work and financial realities, I can only do the best I can with what I've got. I have to give back to this list somehow.  (Eamon Lee)

Rule

This goes out to those of you who taper under power. What materials have you had experience with and what were the results. My original plan was to use maple, then that resin impregnated stuff (I think Winston uses it but the name escapes me), and finally 6061 aluminum.

Maple-

Assumed Pros:  Cheap and easy to work with
Assumed Cons:  Stability of material (I know were only talking 1000'ths...but we ARE talking 1000'ths!!!))

Resin Stuff-

Assumed Pros:  Stability and easy to work with (so my plastic guy says)
Assumed Cons:  Probably expensive

Aluminum-

Assumed Pros:  Stability and cheap
Assumed Cons:  Most difficult of the three to work with

My plan was to bolt the blank 1/2" x 1 1/2" pattern onto my carriage, square it up with the spindle shaft by passing over it with a flat milling cutter, and then impart a taper after shimming. I can see doing this with the resin and maple,  but not with the aluminum. Seems to me it could get violent.

Any experience is appreciated, but I can understand why you would want me to shut up and find out for myself, it's cool, I know the dues paying deal....

Thanks for your help just the same. I hope to be able to get something to Todd or Bob M. (see the pictures here) before too long as I promised before the holidays (pictures, materials, costs, experience, observations, blah, blah, blah....)  (Eamon Lee)

    My favorite material for templates has been MDF.  It is easy to flex if you want to change the taper a bit, it is not hard on the cutters and is pretty darn stable, unless you soak it in water.  6061 is hard on cutters as all aluminum is.  It is easy to drill.  It is easy to cut flex relief cuts into if you want them.  It does not warp.

    I made a nice brass template one time, but because I had the stock anyway.  I would never pay for brass.  Try MDF.  It is easy to go to the lumber yard and ask them to rip out a year's supply for you.  (Chris Lucker)

Rule

All of this talk about roughing mills and finish mills has definitely peaked my interest on how to increase my laziness. I don’t know about the rest of you but whittling the stick is now has become less exciting when  you only have 17 to go and you just had to "chuck" the current strip because a mysterious dark weak spot has just appeared. There is a lot of time invested in one strip for us hand planers.

So how do I go about getting a nice hand planned finished strip without all the hand planning? Oh yea! I am also cheap and spending $3000-4000+ for a mill is not on my to do list. My search for the solution began with Milwards Book. A very good place to start. Building a mill looks like fun but then I hit the cost for the good cutters $150+ Next!.... I then turned to the page with the end face mill and thought I would give it a try. After buying some oak ply wood, aluminum angle, and a $20 HF hand trimmer and  some time I ended up with mill. It uses your planing form or you could actually use wood forms also.

So I gave it a run. I used my roughing beveler to take the strip to a 60 degree. I then placed the strip in the end face mill and made 2 passes on each side. I ended up with the strip 5 thousandths over the forms. I then took my plane and 212 and finished it up. All in all it took about 15 min. Not to bad for an afternoon at Home Depot and a couple of bucks. (Adam Vigil)

Rule

I've recently starting thinking about building a tapering mill similar in concept to the tapering part of the Bellinger Roughing and Tapering machine.  (Sorry, I just can't stop myself).  I'm probably going to stick with something fairly simple.  I've seen some posts on the tips site that say this can be done with a motor connected by pulleys and belt to a shaft fixed in ball bearing pillow blocks.  The cutters, if I read things right, are attached to the shaft.  I've seen the cutters I need (2.75" double angle, 1" hole) in the MSC catalog.  What I couldn't find was how you attached the keyed cutters to the shaft.  Is there a ready made arbor for this?  If someone who's fooled around with this sort of thing could point me in the right direction, I'd be grateful.  (Bill Benham)

    Keep looking in the MSC catalogue, you will find shaft collars for a 1" shaft. They are just a thick metal ring with a set screw in the side, use them to position the cutters and hold them tight together, you will need 2. The pillow blocks come with shaft locks that cam  into place on the pillow block and have set screws to lock the shaft. You will also need a short piece of 1/4" key stock, you can get that at the hardware store.  (John Channer)

Rule

I have a 3/4 hp motor 3450 RPMs with a keyed 5/8 shaft. Does anyone know where I can get an arbor to fit the shaft so I can fit my cutters. I've seen pictures and most have a threaded type arbor.  Or should  I make my mill with a separate shaft and pulleys?  (Bill Tagye)

    I don't think it's a good idea to run a precision cutting tool off of the motor shaft.  Find something built for the loads a cutting tool has exerted on it and power that with a pulley and belt from your motor.

    My $0.02  (Brian Creek)

    I would definitely look into pulleys and a pillow block set up. You can get the needed speed that way. Try McMaster-Carr, Travers or similar suppliers. For example, my Bellinger runs on a 3/4 hp 3450 rpm motor. I wish I had pulleys so that I could get a cleaner cut when tapering.  (Bob Maulucci)

Rule

A friend of mine and myself are in the design process for a Spline Milling Machine and I was wondering---

With a feed rate of about 6”/second; at an rpm of 20,000 at the two flute cutter (router bit), how many thousandths should I reasonably expect to take off a strip per pass?

There are hold down bearings both in front and behind the cutter with between 40 and 60 pounds of downward pressure holding the cane into the form.  (Ren Monllor)

    My first reaction is that your feed rate seems pretty high.  If you think of advance rate per tooth cut you are at .009 inches.  A 10" table saw with a 60 tooth blade would be about .002 inches per tooth at the same 6"/second feed and it is pretty hard to feed a table saw that fast.   As for depth per pass, that depends more on cutter power than anything.   What size router are you planning on?  (Rick Hodges)

Rule

Those that use mills to cut strips to final dimensions, are your cutters 60°? Or are your cutter flattened out a little, say 60°30', or 61°? I've read in some places the old timers used cutter that had a flatter angle of attack. If using 60° cutters, do you have any problems with angle or strips fitting together?

I'm finally tooled up and have the material to TRY and make some cutters. It would sure be easier to mill them to 60° than trying to build them at a flatter angle.  (David Dziadosz)

    I believe the Morgan Hand Mills use two 60° cutters spaced at a 61-1/2° angle apart to plane a spline at 61-1/2° so that the outside edges of the splines come together with a slightly increasing gap to the center of the glued up blank. If I'm wrong about that then I'm sorry for the misinformation and will accept public castigation.  (Larry Swearingen)

      That would be 61.5 for hex, 46 for octs, 73.5 for pentas, 92 for quads and the cutters are triangular inserts.

      You can see this here.  (Scott Grady)

      You could be right about that Larry but I have to wonder to what purpose they do that. Is the cosmetic appearance of the rod more important than integrity of the glue joints? Are they doing that to hide glue lines at the expense of the best glue joints? Or is a very small gap in the middle better because it replaces bamboo with glue? My homemade beveler does 60 degrees and I can usually accomplish a 'no glue line' look with that. But is that the best way to go? Just wonderun.... (Don Ginter)

        I'm not about to start a big argument about this but I'm sure it is done to minimize the glue joint thickness at the outside.  I doubt if it seriously affects the glue joint integrity as with most glues at least "some" small amount of space is needed for glue.  Otherwise all the glue is "squeezed out."

        I just did a CAD layout of the joint gap for a section of  a rod butt of 0.375" diameter that would be produced using  the 61.5° cutters.  At the inner part of the section there would be a gap of 0.0055".  Or 5-1/2 thousandths. Midway out there is a gap of  half that or 0.0028", less than 3 thousandths. I have never heard of anyone who used a Morgan Handmill having delamination problems so do not think is is a practical problem.  (Larry Swearingen)

          If epoxy is spread too thin, it is weaker. It needs to be a layer of a few thousandths thick for strength.  (David Dziadosz)

            Yes, so it does need to have a thickness David, and not being an epoxy builder I can't recall what the thickness should be. I believe that Wayne Cattanach is up on all that. And this leads to the question of, if there is a 5.5 thousandths gap in the middle then how much epoxy thickness is there on the outside of the rod. Whatever it is, you can add that to the 5.5 thousandths. With other glues the question becomes perhaps a little different.

            But in the end, as some would say, it probably doesn't make any difference. I would just add that what makes no difference to me and doesn't matter to me may be extremely important to another rod builder. So maybe a good discussion on the topic isn't a bad idea after all.  Especially when one is going to put a lot of work into making a beveler that is the optimum he can achieve.  (Don Ginter)

              I build using the MHM, and glue with epoxy. I can see no gaps in the glued sections that I have sawn off as selvedge, even under magnification. I have no doubt that there is some interstisial areas that are epoxy filled, which become an integral part of the structure.

              I have been building and fishing rods built with same brand of epoxy for 16-17 years, some of them fished hard and heavy, with no signs of delamination, glue lines or any undue deformity.  (Keith Paskin)

      You can buy them for either 60 or 61.5.  (Doug Easton)

    Most of the old mills and bevelers (and many of the new ones in use today) used 60.5 to 61.5 degree cutters... no big deal to get them resharpened at a good shop.  Mine uses true 60 degree mill cutters.  No problems with the angles or quality of cut.  (Bob Nunley)

      This is what I was wondering! A 60° cutter would be a lot easier to build! Can the angle become narrower as the mill cutter comes around? Not on the MHM, but like on a spinning type cutter.  (David Dziadosz)

      I'm using saws, so I can set the angle to whatever I want it to be by rotating the angle of the spindles. For the hexes, I'm currently using 60 degrees. Haven't quite gotten around to experimenting with the slightly larger included angles yet.

      I did a lousy job of flattening the top of my vacuum hold down. I had to strip all the gasket material and adhesive off the hold down, and I have to resurface the hold down. I didn't have an accurate way to determine the flatness of the top, and it showed up when I started running the saws to cut longer strips. (Mark Wendt)

Rule

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