Bamboo Tips - Tips Area
Cane Prep - Nodes


< Home < Tips Area < Cane Prep < Nodes

Rule

Ever wonder the minimum space between nodes you need to be able to use a Chevy 6 or spiral node pattern, and still have maximum distance from the ferrule to the first node, and from the last node to the tip on a two piece rod?   All these assume a node spacing of 1 1/2 inch, or 9 inches total, and you’ll have one node possibly under the ferrule and one possibly under the tip.  The first to second node measurement is given, the rest of the spacing will be greater.

7’0” rod -- 16 1/2” minimum from the first to second node.
7’6” rod -- 17 1/2” minimum from the first to second node.
8’0” rod -- 18 1/2” minimum from the first to second node.
8’6” rod -- 19 1/2” minimum from the first to second node.
9’0” rod -- 20 1/2” minimum from the first to second node.

(Martin-Darrell)

Rule

On the last rod I did, I used a different technique for prepping the nodes.  I split the strips first, and then dressed the nodes themselves on the individual strips.  To do that I used a stationary 1" belt sander.  I took off the ridge on the enamel side and dressed the area pretty flat.  I also took off some of the back side of the strip which allowed the node to be pressed flat without compressing it too much.

Does anyone else use this technique or does anyone see any problems it would cause.  It seems to work pretty good on the last rod with the exception of 1 strip I messed up do to inattention.  (Scott Allred)

    That is a fairly good method. It is similar to what you can see Glenn Brackett do in the Winston Waters video, except that he flattens them with a disc sander. I think that if you keep the enamel side on, take off the back side (like you describe), and then press and straighten while flattening the node with the notched vise jaws (to put the lip into), you will love the results even more. Then there is so little to file off it is scary. I just did two tips worth of strips in the shop this way, and they are great.

    Here's what I did:

    • Plane the pith side flat.
    • File the pith side under where the nodal bump is. I have a rounded file that creates a small dish shape (gives somewhere for the node to displace to).
    • Heat the node as usual.
    • Straighten side to side with Ray Gould's node press. (Just built this weekend). It is great. I do it quickly and I think about the sides of the press I am going to use while I am heating the strip.
    • Immediately put the lip of the node into the notch in my bench vise and press.
    • Leave it in there while I heat up the next strip.

    Warning: If you heat the nodes again in any way before glue up, be prepared to press them straight again. I am going to heat treat the strips before hand from now on.  Last week I had four great strips that went right back to crud when I heat treated before final planing. (Watch the Digger video, he heats the whole culm before even splitting).

    Works for me.  (Bob Maulucci)

Rule

After reading about "linishing" and splitting (again) last week, I was wondering why I haven't seen a discussion of filing the nodes BEFORE splitting the culm?  The direction of the power fibers at a node looks rather random.  Since the direction of a split along along the entire culm is aided/determined by the direction of the power fibers, would the randomness of the fibers precisely at the node, perhaps, send the split at a node off course?  I understand it would only remove part of the randomness, but would the "every little bit helps" model apply here?

I built a North Carolina redneck "linisher" this weekend (duct taped my belt sander to the garage floor) and smoothed the nodes before splitting on a culm.  I only took it to ~3/8" as I was splitting for a butt section, but it sure seemed to split straighter with less effort. (David Smith)

    I'm a big believer in "pre-linishing"  my culms.

    I thought that everyone linished the culm first and then split.  I linish the outside, split in half and knock out dams, then linish inside before continuing to split.  This is important to get really good splits as you get down to final splitting.  At this is how it works best for me!!!  I have tried other ways with less success.  (John Kenealy)

      It's been my experience filing the nodes makes splitting noticeably easier.  The only drawback is you might be taking extra time filing some nodes that might be trimmed off later when you do your node staggering.  Otherwise, splitting is easier after filing.  (John Long)

    In the beginning I would file the nodes, but then it occurred to me that the upright belt sander would make much shorter work of it, so I put a 1" belt, 120 grit, on the 2" upright belt sander, a source of illumination on the underside of the table so as to be able to see what I was doing against the belt, and started removing the majority in this fashion. It does make splitting easier, both in terms of the effort required and keeping the split from wandering through the node. I also hog out the dams on the inside  of  the  split  culm  "halves".  This helps,  too.  (Martin-Darrell)

    I always do some initial preparation on the nodes when splitting.  I've found that the splitting runs much more "true" when the nodes are reduced in size both inside and out.  After I get my initial six strips from a culm, I whack away at the pithy dams.  Next, I hold the outer nodes of each strip against a large diameter drum sander -- but only enough to remove the ridges.

    Then I'm ready to split the narrower strips.  I continue leveling both the dams and the outer nodes (only if needed) as I split finer and finer.  It all has to be done sooner or later anyway, so I figure I might as well try to help myself by preparing the nodes as I split.  (Bill Harms)

Rule

Is it possible that bamboo can be too dry from storage to properly press/displace nodes?

I live in an old house that has  been converted into four apartments. The landlady lets me use part of the basement to make a few rods and it's really dry. There are four furnaces and two large water heaters with standing pilot lights,  in the basement. During a good rain, water runs in and gets very wet, then within a few days it's bone dry again.

When I heat nodes, they seem to get brittle instead of flexible. They seem to press OK, but when I heat treat they pop back up. Not all or very much, just enough to be annoying and require more attention.

Is it true that some moisture is required for the strip to be flexible and the lignins to adhere and stay flat after heat treating? Is this part of the reason for soaking strips in water? How do you know when all the moisture has been removed when heat treating? Has anyone tried the impregnating process with water, to turn a 3-5 day wait to minutes, to soak strips? It goes against my grain to add moisture, but if that's what I need to do, then that's what I'll do!  (David Dziadosz)

    Just taking a guess here, but it sounds to me like you are overheating the nodes during the flattening and straightening process.  In my experience, there really is a "sweet spot" when heating nodes; too little and the node won't soften, too much and the node gets brittle.

    For years I tended to err on the too little side, forcing me to reheat the nodes.  With time I've learned to "feel" the node softening and immediately work the nodes.  With my particular setup, the nodes get just right at about the same time that the very first, very faint light brown scorching begins to appear on the pith side.  If I blackened nodes like so many I've seen, every one of them would snap.

    I don't know the particulars, but let's assume that bamboo first softens at "X" degrees Fahrenheit.  My guess is that at every degree above "X", the bamboo gets less and less soft.

    Others?  (Harry Boyd)

      I just got Bob Milward's book, and He has some surprising things to say, but the one that impressed me was that heat treating past the point at which the ambient water is driven out degrades the integrity of the material.  The more it is heated the less bonding of the fibers. and the consequent more brittle He also makes the point that trying to displace nodes is largely an exercise in futility, since any reheating will cause them to pop up again.

      David, Not taking issue with Harry, because I agree with him, but I would add that judicious filing of the nodes is necessary, and the heat applied to the cane should be applied like you are cooking a medium steak ==  all the way through.  Charring the outside and trying to correct the node, will inevitably cause the node to fracture.  Remember that the power fibers are disrupted at the node, and filing them is not all that much of a problem.  Over heating is!!!  Todd Talsma's Tips has a couple of entries that address your problem. Take a look  (Ralph Moon)

        I've never been one to let honest research or real truth stand in the way of my opinions, have you?  Just because Consumer Reports tells me that car brand T is better than car brand C doesn't mean I have to lust after Toyota's more passionately than Caddy's, does it?  (Of course I own two Mazda's, and no Harley's)

        That said, some of my experiences don't line up with Bob Milward's well-researched findings.  I'd be afraid NOT to heat treat to the point where there was some significant color change.  Another point of disagreement concerns nodes.  If the pressing and straightening is done juuuuussssttttt right, they don't pop back out. I agree though, judicious filing of nodes is necessary.  But the key word is judicious.  (Harry Boyd)

        Adam Vigil, who used to be on the list, wrote a article for the planing form on a heat treating test that he did and he pretty much came to the same conclusion as Bob Milward. 225 degrees for 1 to 2 hours and 350 degrees for 30 minutes. Soon as the cane starts to darken you're caramelizing the sugar and lignin (Bob Milward) and loosing strength. I cast a few of his rods at Corbett lake over the last few meetings, none were brand new and all had been fished a lot (steelhead, salmon, sea run cut throat and kamloops trout) and none of them had any kind of set and they were  blond and some were dark. He uses leather dye diluted with metal hydrate to  darken his rods.  Looks like a nice dark rod.  (Patrick Coffey)

          The darker the cane the more brittle it becomes! But a dark rod is greater then the sum of its parts. The bending required to break a rod section often exceeds normal use. So flame on! (just not to much)  (Adam Vigil)

            One of the wisest things I've ever seen on the list.  Good words.  I hope lots of folks here them.  All good rods are more than the sum of their parts, IMHO.  (Harry Boyd)

Rule

After lurking on this board, reading everything I could get my hands on and collecting and building enough tools, I thought I was finally ready to actually get started. I've already made lots of mistakes on practice culms and figured that it was time for the real thing. I assumed I'd get farther than I actually did without coming to this group for advice but that's where plans and reality parted ways. So here goes....

I'm having trouble with bamboo strips bowing up after straightening the strips at the nodes. My initial attempts had me sanding out a bit from the pith side of the node and soaking the strips overnight. I then heated the strips at the node, pressed the node flat and then straightened by pressing the sides. What I ended up with was strips that were badly bowed from one end to the other (about a 6" overall bow in a 48" strip). ! At first, I thought this was due to soaking the strips prior to straightening so I thought I'd try this without soaking. Again, I started with reasonably straight strips but ended up with the all to familiar bowing.

I had reasonable success with one set strips by placing them on flat table after straightening and putting some weight on top until I was ready to plane them. Seems like more of a hack than anything - but it worked!

As much reading and preparing as I've done, I don't recall reading anything about a problem like this.

Any ideas what I'm doing wrong or suggestions about what could be done differently?  (Pat Higgins)

    Starting is the most important part of learning. Now from what I do and have talked to other builders as to what they do I can tell you that straightening nodes is primary and you really do not have to worry about the sweeps. Once you start planning you will remove a lot of material and when you are at the 60 degree stage you can bind them and heat treat. This will remove  most of the sweeps. As you continue to plane you will see that the sweeps are greatly diminished. When you get to glue up just make sure the blank is straight and it will dry the same way.  (Adam Vigil)

    First, if you're going to soak the strips, overnight is not sufficient to achieve much, if any, benefit. Try three days minimum, with four being preferred. Second, it is not at all unusual to have strips with a bow running from end to end, both after straightening nodes, and after heat-treating, though the bow will be less pronounced after heat-treatment. Don’t worry about it. Much of this will come out as you plane to final dimensions, and the cane has more give to it. Upon glue-up, you'll get the rest of it out -- what little there is. It's not a problem, so you may now find  other areas for concern,  and trust me,  you will.  ;o)  (Martin-Darrell)

    I plane my strips to approximately .010" to .020" over size, then bind and heat treat.  The heat treated strips are quite straight.  However, as you plane to final size the strips will bow up.  I take this as evidence that internal stresses are being relieved by the planing.  The "bow" has no effect on gluing.  (Ted Knott)

Rule

I guess I did not save the post about two weeks ago, so I don't know who to thank for this. A post last week or two mentioned a German rod maker that flattens his nodes without filing them first. He used a plate??? with a slot in it or something to that effect.

I just finished flattening 18 strips and that is the way to go. It may not be traditional but the nodes came out beautiful. I took a length of 1/2" X 1/8" aluminum strap, (hardware store stuff) the length of my vise jaws, filed a narrow "V" groove across the middle to accommodate the node ridge and attached it to one vise jaw with double sided tape.

I soak my strips for three days and it don't take much heat to soften the nodes up. After the nodes were flattened there was only the little narrow ridge to be filed off. A couple of strokes took care of that. The enamel is still up to that ridge line.

All I can see is a fine line where the ridge was. On the finished rod there will  be just a  narrow line  where the node was or none at all.. Will report on how it looks when I finish up the blank. I am real satisfied with the results. It really seemed easier to flatten the nodes this way.  (Tony Spezio)

Rule

Now that I have given it more of a try, I want to say with great confidence that putting a groove in the vise to accommodate the lip of the node is really ingenious. I have tried it several times and had good results, but today I removed the jaws from my bigger vise, flattened them, and put the groove in one side. Now I have great results.

My wife came home to hear me talking to myself in the basement shop, "Holy *(%^!"

She screamed down, "What is it? What's wrong!"

SO now I have a whole rack of strips split out that I won't use because the nodes are too wide.  (Bob Maulucci)

    I started using this method when it was posted a while back. It really makes a difference. The last three blanks have real small node areas. On some nodes there is just a line where the ridge was. Lot easier to do the nodes too. I do mine after I soak them No burning and the nodes don't seem to be hard like they are doing them dry.  (Tony Spezio)

Rule

Here is how the Waara node press works:

It is a horizontal toggle clamp in which the piston presses the strip against a notched backstop.  There is an additional piece which slips over the backstop for smaller radius bends.  The piston is adjustable (in and out) and the head is narrow one way and by rotating 90 Degrees, is about X2 wider.

There is a foot on the front end which elevates the press for a better viewing angle making straightening a sit down job. 

The press should not be attached to a bench or held in a vice.  You can do straightening anywhere - just grab the press, your strips, a small propane heater and go.

You can straighten during final planing or even a glued-up section.  It’s the only thing I have used for the past 15 years.  Bill "done good" with this tool.  (John Long)

Rule

I prefer to file nodes on the culm when making flamed rods so that I can flame the culm after the nodes are dressed but have never liked the time and effort I have had to put into hand filing.  I just discovered (maybe I'm the last to do so) a sanding flap disk for my 4.5 " portable grinder.  The things are available in grits from 40 to 120 and are like 1" wide shingles arranged on the disk.  I can cradle the culm and  rotate it while making short work of the nodes.  Seems to work great.  (David Van Burgel)

Rule

I found the following tip, originally from Chris Bogart, on the Tips Site.  Not sure how old it is. Anyone used or using this method?  I've only built nodeless rods to date (and only a single handful at that), but this way of doing things sounds very attractive - no straightening of the nodes or sections.

snip

===========================================

You have a Medved style router beveler - let it do the dirty work for you.

I gave a demonstration at Roscoe this year on this procedure. BTW, all the strips for the gathering rod were prepared w/o heating, straightening, or pressing. Nobody was the wiser and the rod turned out fine.

Next time try this:

1)  Split culm to quarters - knock out dams, stagger, and cut to length.

2)  Using a belt sander - sand your nodes flat!

3)  Heat treat these sections - add an extra minute or two to your normal time

4)  Split quarters into quarters - you end up with 16 sections.

5)  Now run these through the Medved beveler to get triangles.  When the strips are about .050 - .060" oversized then (do this) - after you run it though the beveler (and before adjusting the cut), run it a second time with the enamel side up! 

Repeat the previous step until the strips are down to just over the dimension for putting into your form.

You will end up with 16 strips for butt / mid and 16 for the tips - if you screw up the planing then you will have a heat treated prepared strip to take its place. The router has done all the work for you. (Chris Bogart)

============================================

end snip

I have some questions for anyone using this method or with thoughts about it:

1) Can I heat treat after working the strips to triangles (or, why heat treat before final splitting & beveling)?  I'd probably have to make 3-4 runs with my heat gun oven to treat a culms worth of quarter sections.

2) Can I reduce the size of the strips with the beveler using the squaring tray before going to the 60 tray and get the same net "Straightening" effect?  The design of my hold downs on my beveler wouldn't accommodate a strip 3/8" wide in the 60 tray.   (Bill Benham)

    Following Alexander Pope, who said "fools rush in where angels fear to tread" I will take a stab at this one. The bottom line is that the method works; however, a lot of makers would not agree with the approach.

    The heat treating triangular strips will work fine. Many makers heat treat after establishing the basic triangle. Most bind the strips together and use an oven. It sounds like you are heating them by passing a heat gun over them. That would work, but you might want to have some way to measure the amount of heat applied so that you have some measure of repeatability.

    The squaring of strips was a major aspect of a talk that Chris gave at Grayrock several years ago. He used the technique you shared, but split oversized strips that were then squared on the beveler. This cut away the kinks surrounding the nodes and gave perfectly straight strips with no straightening. Then the strips were beveled.

    There are are several criticisms of this method:

    1. It is equivalent to sawing, and does not follow the grain as splitting does. This has been debated endlessly with no resolution.

    2. It wastes cane. You might get one rod and some spares rather than two rods. The cane is the least expensive part of the rod, and it isn't exactly a scarce commodity. On the other hand, many makers are appalled when a single scrap of precious cane is wasted. This has been debated endlessly with no resolution.

    3. The sanding may weaken the node by removing material that should be displaced instead. This MAY be the one valid criticism. I used a similar node treatment on the only rod I ever broke. There were many other possible reasons why it broke, and perhaps even a different node treatment would not have prevented the break (caught the steel wool on the tip when finishing). But I personally try to remove as little material as possible. This has been debated ... you get it.

    My bottom line is that it is a good method, but I would heat and press the nodes instead of just whacking them off. It seems especially appropriate for Morgan Hand Mill users- if the strip isn't straight as an arrow you  will have  problems.  (Jeff Schaeffer)

Rule

I suppose that all any of can say about rodmaking and how we make rods is we use what works for us!  I dread the process of straightening and pressing strips and nodes, being as it is such a repetitive and mind glugging operation, but it's nevertheless (in my opinion, at any rate) one  which has to be done.

My process, very briefly, is this :

  • Sand and file the nodal ridges flat, or until the black mouldy crud has disappeared from the trough
  • Split the culm
  • Stagger the nodes and cut the sections to length
  • Plane the edges of the strips to semi-squareness
  • Using a Bosch heat gun on medium setting, I work my way down each of the strips, heating and straightening and pressing as I go.  I heat until I first feel some plasticity in the strip, then straighten or press or whatever;  and no, I don't worry about a little bit of charring.  If I were to char so badly that the discoloration did not disappear when the strip was planed, though, I would consider that I had stuffed that strip and would replace it with another.
  • When I have finished pressing and straightening, I tidy up the sides and pith sides of the strips a bit more, so that I have a very clean, square,  and straight strip ready for planing a rough 60.
  • When I finish a section, I tape the six strips FIRMLY together with masking tape and lie them flat until ready to rough plane them.

I don't get too carried away about the nodal scar.  To me my nodes are not so wide as to be ugly, but the are not kind of hair's breadth either - about a centimeter, I guess.

The biggest advantage of this fussy business of squaring and tidying is that I then commence rough planing with a straight, squared, stable strip which sits well and true in the form and delivers a good 60.

For what it's worth, I have never had any trouble with fragility using this technique,  and some of my rods get thumped pretty hard by their owners, and by me.  I think success comes from not doing anything to excess - neither heating, nor pressing, nor bending.  (Peter McKean)

    I hope I am not stepping on any toes with this.

    Why file off the nodal ridges before splitting the culm. I did on the first couple of rods only to discard lengths of bamboo that had the ridges filed off and nodes sanded. I find that splitting the culm first,  staggering and cut the strips to length. After the strips are cut to length the inner node webs are sanded off with a small sanding drum mounted in a drill press. I don't do anything to the inner webs till now. If you want, you can hit the nodal ridge at that time. It only takes seconds to do it all. I leave the nodal ridge till after the node is displaced or flattened, (whatever pleases the maker)  using a notched plate for the ridge. It takes a couple of passes with the mill file to remove the ridge and the nodal area is clean and flat. This takes the drudgery out of node work. For me, nodes are no problem at all. Give it a try, it might work for you too.  (Tony Spezio)

      I agree with you, and in fact I think that all things being equal, the later you attack the nodal ridge, the better, as the arcs you have to deal with are smaller.

      The reason I do it when I do it is, and I omitted to say this, I flame the culms  and I find that if the ridges are gone before I flame, I am able to flame a bit of color into the area of the node.

      What you lose on the swings, you gain on the roundabouts, I guess.  (Peter McKean)

        That is a good enough reason for removing the ridge. I seldom make a flamed rod. When I do, I flame the individual strips after I do the node work.  (Tony Spezio)

      I actually use the "little drum on the drill press" to remove the outer ridge before splitting.   Then split in two and knock out the nodal dams.  Then split into relatively flat strips and at that point back to the drill press sander and take off the insides. This way when you're splitting it's easier to guide the split across the nodes without it going haywire.   (Henry Mitchell)

Rule

Understand that sanding nodes is a short cut in getting the rod  finished. That is why production makers did it. Makers of the past did not sand the node because it was the right thing to do, it was simply the quick thing to do. Now what is the point, other then being lazy, in sanding nodes? Is it a fashion statement because some makers like big node scars or is it that the maker can not master the skill of taming the node?

If sanding nodes starts you off making rods, then that is okay, but all makers should learn to minimize the node scar just to go that extra step on a hand crafted item that separates itself from the rest.

If nodes are your nemesis and hate pressing and planing them do this. Saw the strips with a table saw, sand the nodes on a linisher and mill your strips. Your strips will come out straight and will look just like a Hardy Bamboo,   if you like that kind of thing.  (Adam Vigil)

    So what your saying is if a rod maker sands his nodes he's lazy! And his rod is just sub par!  (Bill Tagye)

      Let’s stick to what I say and not what I didn’t.

      Quote: "Now what is the point, other then being lazy, in  sanding nodes?"

      That is the question, nothing about being sub par, whatever that means. Many makers new and old sand the nodes. Why? Being lazy is one answer, what are the others?   (Adam Vigil)

        in all do respect...

        Some maybe of the school that heating and pressing the nodes weakens the cane...

        Some may argue that by heating and pressing nodes you are sacrificing performance over looks...

        Here's a question... Name any material that you can heat then collapse it's structure while retaining the same structural integrity?

        I have thought this from the jump and haven't heated and pressed nodes (I call it "burn and crush") for years...

        Bottom line, it works both ways so go with what you know.  (Dave Collyer)

        I don't sand nodes I soak, heat straighten and very gently press followed with a gentle planing of the remaining ridge. I get nodal scars that are quite acceptable to me and not much larger or the same as "traditionally" pressed nodes. I have a practical reason other than laziness for doing this. It gives me the dead flat enamel side I need to make the Morgan mill work best. I get better strips with fewer chips at the nodes. That's why I do it.  (Doug Easton)

        You are correct when you say that straightening the node is better than sanding it flat. The heat used for correcting bends and kinks is no more than that used for heat treating, if done properly. And we all heat treat, don't we?

        However, the term "pressing" the node implies that the node is deformed under pressure. That's not good.  I soak, heat, straighten, then clamp to hold the node straight until cool -- about 30 seconds in a metal vise -- just long enough to heat the next node on another strip.  (Ron Grantham)

          I am right there with you. Same procedure I use. Dewey asked a question and it was pretty silent here. I asked the question the way I did to get some answers. Its good to hear why people do what they do.  (Adam Vigil)

          I'm working with a well respected maker at the moment. We have to do a ton of rods real quick so, sanding nodes is the only way to do it  ;)  Not to mention that the nodes can not be pressed in the cane that we are working with. This stuff is heat treated as a culm. When I first started working with him and he told me to sand all the nodes.  I looked at him like he was crazy. Then he gave me a strip, lamp, and vise, and said press it. I gave up rather quick.  So to answer your question. If someone is making only a few rods a year, pressing, (I think), is the way to go. It just looks better. If you are having to pump out a bunch of blanks, then sanding is a better option. I don't think it is a "lazy" thing, more of a time saving issue.

          I have learned that there are so many different ways to do this bamboo thing, mostly from this List and things that I have read on the net. Everyone has a method to their madness, and no single way is the Law. I think that a lot of makers make this a lot harder than it really has to be. These things are just fish poles, after all. (Robert Hicks)

            "I don't think it is a "lazy" thing, more of a time saving issue."

            Precisely.  I've only got so much time to devote to this hobby, and have way more rods that I'd like to build than I have time for.  I want a decent rod, made by my own two hands, that looks good and fishes well.  I don't aspire to perfection, so I don't give a rats arse if I have large "node scars".   So I sand the hell outta them.  (Bill Benham)

            You've heat treated the entire culm.  Would flaming a culm before splitting have a similar effect thereby making it more difficult to press the nodes?  (Tim Wilhelm)

              I have had no problem when I flame the culms. my problem was having the hump come back. I think I have solved that with help from the list. This is the new process that has worked really great for me.

              I:

              • flame the culm
              • split it into workable strips
              • heat to straighten
              • square up the strips as best as possible with a plane
              • on the pith side I plane off the pith
              • I sand the node on the pith side with the edge of my belt sander so there's a half moon under the node (this has made a big difference!)
              • on the enamel side I take off the ridge of the node with a plane (this really helps with leaving a very small scar (IT'S THE NOT LAZY METHOD)
              • heat the node without changing the color and press it
              • when it comes out of the vise I sand any imperfections

            After this, the node is nearly perfectly flat with a scar no larger than 3/8 of an inch if I'm lucky. I hope this makes sense.  (Bill Tagye)

                The method you are using is what a lot of us are using and it is not considered "sanding the nodes" When I ask about sanding the nodes I am speaking of using a linisher, belt sander, disc sander to remove the entire nodal hump on the enamel side. This method can leavea node scar of a couple of inches.

                I know you took exception on my node sanding question. But it sounds like you are straightening and pressing not sanding.  (Adam Vigil)

      Bob Milward says that if  you heat  to the point the cane changes color, then you have weakened it.  That applies to heat treating as well as nodes and straightening.  He's not talking about charring, just darkening.  And he seems to have the data to prove it.  (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive)

    Nobody worries about the damage to nodes from removing lateral kinks, I doubt pressing them is any worse. On the other hand, if someone were to do an experiment that showed sanding was ultimately stronger I'd be happy to hear it.  (Henry Mitchell)

    I don't think anyone yet has addressed what "sanding" consists of?  I remember seeing pictures (maybe the Winston video?) of a disk sander that had to be at least 12" maybe 18" in diameter. Now that's a freaking sander! You slap a strip on that baby and flatten a node and you've done some sanding! I'm not sure of course, but don't most of us guys sanding any portion of a node using something CONSIDERABLY smaller? Not to mention finer (sorry for this to all it offends) grits? I don't know about you’se guys, but the sander I use is only an inch wide and a wore out 220 grit belt. I only use it to smooth out the node instead of a file. I still have to heat, press, scrape and sand nodes. There's sanding and then there's SANDING!  (Mike Shay)

      I use a belt sander on the pith side(as I really don't think size of area sanded on the pith makes any difference) and a Delta with a 1" belt on the node. Same grit as Mike mentioned on the Delta. FWIW, It works great!  (Dewey Hildebrand)

Rule

I'm working on my first rods(s).  I have my strips split (which actually went very well after I got the hang of it), nodes staggered, and strips cut to length.  My question for today is on nodes.

I didn't do anything to the nodes before I split the strips.  What's my best course of action now. 

I've tried heating them and then putting them in a vice with a vertical notch in one side as described in the tips page, but this really hasn't given me as flat on area as I'd hoped for. 

I've also tried taking a plane with a very sharp blade set to take a fine cut and planed the node area flat.  For me this seemed to work very well.  I'll probably restart a fierce debate, but other than appearance will this affect the performance or durability of the rod?  I've read some things in books from the 1950's that describe completely sanding off or filing off the node.  Planing can't be much different can it?  I understand that I'll end up with a large nodal area.  (Aaron Gaffney)

    There are many ways of getting the nodal area flat that you can use.  You can sand them, file them, file and sand them, plane them, plane and sand them, you can even cut the buggers out.  As you can probably tell, people have or do use any of these methods.  What you want to do with them is really up to you.  Try the different methods out and go from there.

    Here's what I've done in the past.  After splitting, I plane the back side of the strip fairly flat.  Then, I file and sand the nodal ridge off the strip.  I clamp the strip in a vise with the nodal area above the vise jaws and get them fairly flat.  After that, I flip the strip over and file a little bit of a relief on the back side of the strip.  After all the nodal areas on the strip are done, I drop the strip in a tube of water and soak for a couple of days.  After the strip has been soaking, I'll pull it out and heat up the nodal area over my heat gun and then I'll press the nodes in a vise.

    I'm not going to say my nodes are perfect, but it works well enough for me.  (Todd Talsma)

    Like Todd said, there are lots of ways to deal with nodes. I generally flatten them like Todd then gently plane off the remaining bumps. I have asked several "small node" advocates to look at them and they couldn't tell they were planed. I think that the soaking really helps the planing and after that the straightening. One additional note. Make at least one extra strip for each stagger. You may screw up one or two- ask me.  (Doug Easton)

    Look at a side view of a node and you'll see that the power fibers form part of the hump. If you sand or plane the nodes completely off you will end up with small patches of weak, pale colored material called pith, and there is absolutely no strength in pith.

    As others will tell you, file the ridge smooth, soak the strips, then heat and straighten the nodes. It takes a bit of work, but that's where the 50 - 60 hours to make a rod come in.

    Remember, if a job is worth doing, it's worth doing well.  (Ron Grantham)

      I agree with Ron. The power fibers are offset by the depth of the dip.  I flatten them out (level them).  (Mike Canazon)

      I plane the nodes flat also. The pale colored material you speak of is not pith. It is an area of jumbled bunched up fibers which I call power fibers, but others reserve that name for the very thin fibers just under the enamel. Look at a planed off node with a magnifying glass, and no way will you call that pith.  (Darryl Hayashida)

        I just did an experiment with a two flamed strips planed to final dimension where the nodes were flattened with a plane. I was able to bend the strips (APEX IN) into a full circle. I noted that the nodes were much stiffer than the internodes. When the strips broke they broke either side the node (this was where the highest stress was). Of course this was only two strips and these should be compared with other types of node prep.  (Doug Easton)

          I know there have been several people that have done similar tests and reported them to the list, but as far as I know (correct me if I'm wrong), there hasn't been any scientific research on this.  Of course, since we're dealing with an organic substance, it could be difficult to nail down the data. Any comments from others out there????  (Todd Talsma)

          Are you all saying you plane the enamel side of the strip to remove the node hump?  (Pete Van Schaack)

            I think that's what we're saying.  I've done it this way before and to tell you the truth, I don't think that I'll do it again.  I just didn't like it.  That's just my personal opinion.  I know other people do this and have great success with it, even planing the enamel too (GASP!).  (Todd Talsma)

          As I recall, lumber, where the grain is oriented roughly in one direction, offers less resistance to bending then composite beams that have various layers oriented in different directions.

          We speak of nodes as the weak spot in the bamboo while at the same time acknowledging that rods tend to break on either side of the node.  That seems like a contradiction if indeed the node is the weakest point.

          My suspicions are that the bamboo between the nodes, where the fibers are oriented parallel to each other, offers less resistance to bending then the nodes where the fibers are not parallel.  Stresses, it would seem, would concentrate at a point where the parallel fibers met the nonparallel fibers of the node.

          If that is the case it would follow that staggering the nodes lessens the possibility of a flat spot when the rod is bent.  By removing the node by planing or sanding, one may be reducing the nodal area's ability to resist bending as opposed to flattening the node which would not cause a change in resistance.  For that reason removing the node with a plane may well offer advantages to pressing the node.  (Tim Wilhelm)

        One of the rodmaking myths that really bugs me is that the nodes are the weak part of a strip. If you doubt me, please test for yourself.

        Take an average strip of cane (about .250) and place your hands on two nodes with one node smack in the middle. Bend this strip so that the middle node is at the apex of the bend. The first thing you will notice is that the node creates a flat spot. Now continue bending the strip until it breaks. Remember, you are purposefully trying to break the strip at the point of highest stress which is the apex of the bend or the middle node. 99% of the time, the strip will break anywhere but at the node. Now take another strip or a different part of your first strip and file, plane, sand, or grind the inner and outer nodes flat. Again try the break test and you'll get the same results just about every time. Lastly, heat the node and press it as is suggested in many books. The strip will now break at the node 99% of the time. My theories & conclusions are not only based on repetitive stress testing but also on physical observations made with the assistance of a microscope. The nodal part of the culm is where fibers no longer run somewhat straight and parallel but they intertwine creating locking fibrous knots. This nodal structure is the strongest part of a culm until it is pressed or displaced. When pressing or displacing a node, the interlocking fibers are broken.

        I think most of you would also agree that when a material that flexes with a certain index has a transition to a section that flexes at a greater index (like a nickel silver ferrule on a rod), stress and weak points are created on either side of this transition. Looking back at how a strip with unpressed nodes flexes, you'll see the area between nodes flex while the nodal areas remain straight. The stress is then moved to the apex of the transitional area creating a weak spot.

        In conclusion, pressing or displacing nodes weakens them, while flattening nodal ridges by filing, planing, grinding or sanding is the only way to ensure nodal fiber integrity and strength throughout the length of a strip.  (Jeff Fultz)

          Accurate,  but now take the same strip, heat treat it, and press the node. Some makers actually get charcoaling while heating the node. Now bend that strip and if the node was over heated...POP! nodal area breaks. Thus the belief the node area is weak. The correct statement is the node area is weak if not treated properly.

          If you soak the strips and heat and press nodes you can avoid the  charring and maintain the strength.  (Adam Vigil)

            Does anyone know the exact temperature at which this transition takes place, in general?  (Jerry Foster)

              I can't tell you the exact temperature, but will say that the temperature at which cane softens is probably less than we think.  I experimented a little earlier this week with heating a node or two with stream.  Though it took several minutes, the steam softened the node quite effectively.   I'm no scientist, but steam is 212 degrees Fahrenheit, so the strip could not have been any warmer than that.

              I'll repeat a story I've shared here before.  When I was first getting started making rods, someone asked the List "How much charring is okay when heating and pressing nodes?"  John Zimny answered succinctly, "None."  That bothered me, because I had been charring all my nodes.  I played with it for several months and found that when bamboo first begins to change to a light brown from heating over my heat gun, it is usually soft enough to remain pliable and allow me to work that node without breaking it.  I now heat as little as I can possibly get away with.  I never let them get black, or even dark brown.  Just a little color change at the edges on the pith side.  (Harry Boyd)

                I still can't bring myself to soak strips, however, I have stumbled (bumbled assed) on to something. My previous shop was in a very dry area in the apartment complex I was living. The stored cane became very dry! When prepping nodes, I had to add more heat and they became very brittle. My new shop, is in a partitioned section of the garage. The stored cane is subject to more humidity, therefore it has more moisture content. Now it takes less heat and is more pliable. And planes much easier.

                I think there was an article in the Planing Form about soaking, just the nodes, using a towel and steaming hot water. It would probably be easier to soak the whole bundle of strips at one time!

                I have a idea about putting the strips in a tube and pulling a vacuum, then filling the tube with water under pressure. The supply pressure coming into the house is around 100 PSI. I'm thinking this could cut down the soaking time. Has anyone tried this  process?  (David Dziadosz)

          Again, I agree. Prior to heat treatment a spline will not break at the node. Heating the nodal area weakens it. But I think that you need to line up the power fibers (press or displace) as was previously posted. If you look at a strip from the side you will see by lightly pressing, the fibers can be aligned, as opposed to filing or sanding them off.  And this is about power fibers.  (Mike Canazon)

          I am sure you are correct. It would be interesting to do the same test with pressed soaked strips.

          BTW, How do you handle the lateral kinks without heating and pressing?  (Stephen Dugmore)

          One year ago I have made a search about the nature of bamboo nodes (from the rodmaker point of view) and I am arrived to the same conclusions that you describe. Nodes is a moment of discontinuity of the fibers structure of the culm and the structure of the nodes are more complex than the structure of the other parts of the culm.

          I have used a microscope to 20 powers enlargement, I have made same pictures and I have used a software for remote sensing to enhance the images. Before and after the node heating/pressing. In the nodes the fibers don't go only along the vertical axis, but they made also same curves along the horizontal axis.

          During the pressing. with this type of structure, you have not only the compression of parenchymal material around the fibers (that's OK). but also the breakup and the dislocation of the fibers from parenchyma. That's no good! But in practice you have no effect from this procedure, considering the staggering of the nodes and the bonding effect of the modern glue. Apart this aspect, I consider more efficient for the rod structure to remove a thin part of the surface power fibers by filing/sanding than stressing the structure by heating/pressing the nodes.   (Marco Giardina)

            The power fibers are not aligned from one side of the node to the other. If you look at a strip this is quite obvious. So why not level (press, displace, whatever you want to do) them out so they line up and look close to normal.

            There are many ways to do this, and it seems to me that a few of us believe that the less heat applied to the nodal area equates to a structurally strong spline. It has been well documented that the strongest power fibers are closest to the enamel, so why sand them off?  If you have a dip in a node near the tip I believe it will create a weak spot in the section.

            I know that many of the production rod companies of the past sanded off the nodes, but I believe they had a lot more cane to work with then you or I, and could afford to discard a lot of stuff that I don't.

            When I look at a rod, probably the first thing I see is the node work. Is it small. Do the fibers line up coming in and out of a section. To me it shows the workmanship that went into a rod.  Whether it is an old Leonard or a rod by a new maker.

            I am also curious about the idea of not "pressing" a node, not crushing, as it were. I was in the school of displacement, but I am beginning to rethink that. It seems to me that there are not as many power fibers in the node and by "crushing" them together, you may make a stronger rod.  (Mike Canazon)

              "it has been well documented that the strongest power fibers are closest to the enamel, so why sand them off?"

              When and where was this proven and by who? Or is this just another one of those assumptions that has sprung up and perpetuated itself? Actually the fibers there aren't necessarily stronger, just that there are more of them right under the enamel and they are bundled closer together. Maybe all this is yet another myth we can dismiss.  (Larry Puckett)

                Maybe we could ask the Mythbusters on TV to check this out?   (Rich Jezioro)

            It has already been done.  Read Bob Milward's book.  He went to great lengths to debunk many rodmaking myths.  His book will not teach you how to build a rod, but it has more information per page than any other book on bamboo rodmaking I've seen.  (Robert Kope)

          Isn't the whole purpose of the nodes in the living plant, to give it support and strength, to withstand wind and the weight of  the plant?  How does that translate into a fly rod? You would think, by cutting out the nodes in a nodeless rod, it would be more flexible. Maybe not, since the scarf joints are laced with adhesive, making them stiffer.  (David Dziadosz)

            The bamboo power fibers structure are not different from the structure of the graphite material used for the rods.

            Carbon single fiber have only a strong resistance to the stretch. Also a group of carbon fibers maintain this characteristics: tensile strength only.  If they are confined in a resin matrix they assume the mechanical characteristics that we know in graphite rods. In bamboo the resin matrix is the parenchyma.

            In the case of node the compression in this area can produce not only the matrix compression, but also the lost of contact/contiguity between the the "matrix" and the fibers. Consider also that the two elements have different reaction to the compression.

            In any case, I don't think that pressing Vs. sanding can produce different resistance and mechanical characteristics in a bamboo rod. I think that the two systems are equivalent from the practical point of view. If one of the two  systems had produced more fragile rods, it would be well known and abandoned by the rodmakers community  since long time. It is like the natural selection: a productive system that create problems is abandoned as soon as possible. An example? Animal glues Vs. synthetics glues.

            Anyway I don't think that pressing or sanding nodes produce rods of different quality. Frankly, pressing nodes is not a particular difficult operation that needs a particular knowledge and skill. It is a procedure just like sanding nodes.

            I think that the quality of a bamboo rod is the sum of many elements and processes: I don't think that passing a file on a node reject a rod only for that in the side of low quality rods.  (Marco Giardina)

              The nodes in the raw culm are exactly analogous with the solid dams that some use when hollow building.  In short their purpose is to diminish the tendency to ovality in the cross section when tubular structures are put under stress.

              The stiffness of a regular polygon, which includes a circle, is proportional to the fourth power of its diameter, but when that cross section becomes an ellipse it is proportional to the major axis multiplied by the cube of the minor axis, which is, of course, less. The more elliptical the cross section becomes the less stiff it becomes, for a constant cross sectional area. So, for a constant increase in stress (load) you get an increasing amount of  strain (bend). Hollow built cane rods do not differ in any way from any other tube, and the cure is the same. This is one of the reasons that people think that hollow built rods lack butt stiffness under load, no compensation is made for the onset of ovality.

              There was much discussion about this tendency to ovality when fiberglass tubes became popular, people said they could measure no ovality in the tips of rods when bent, so it did not matter. They were half right, the ovality occurred in the butts, and it could be counteracted by making the butts with a calculated degree of concave taper.  (Robin Haywood)

        Something occurs to me.  Has anyone investigated the nodal area with a microscope or any other form of magnification.  We know the fibers are jumbled at the nodal area but are they continuous?  We are assuming the power fibers run the entire length of the bamboo.  But is this correct or do they end and begin in the "jumble" at the node.  If they are continuous, then cutting even one fiber would reduce the strength of the rod but if they actually end and begin at the nodal area, is this true?  I am convinced that the strength of the nodal area is reduced as the temperature of the node is elevated during flattening, so are we forced to weaken the nodes by either heating or planing?  It would seem that there is no "right" way to treat the nodes but rather do the best we can by either minimizing planing or keeping temperatures to a minimum.  I do not "plane" the enamel side of the strip but I do scrape it; same result but smaller bites.  I flatten before scraping.  (Onis Cogburn)

          I seem to recall that Bob Milward established that the length of the power fibers was very short.  On the order of an inch 0r two.  Interesting concept that!  (Ralph Moon)

Rule

I've got a stupid question. Are the nodes closer at the bottom of the plant or at the top???  (Ren Monllor)

    The only stupid question is the one unasked.  Node spacing is closer at the butt.  (Al Baldauski)

    The nodes are closer at the botton, farther apart at the top.  (Chris Obuchowski)

      And there are also lots more power fibers closer to the bottom.   (Geert Poorteman)

        In his book "Bamboo - Fact, Fiction and Flyrod" Bob Millward says based on his measurements (pp 25-) that TIP sections of culms are stiffer than butts.  (Tapani Salmi)

Rule

Site Design by: Talsma Web Creations

Tips Home - What's New - Tips - Articles - Tutorials - Contraptions - Contributors - Search Site - Contact Us - Taper Archives
Christmas Missives - Chat Room - Photo Galleries - Line Conversions - The Journey - Extreme Rodmaking - Rodmaker's Pictures - Donate - Store