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Main Boards => The Bowyer's Bench => Topic started by: gfugal on March 10, 2018, 02:58:00 PM
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I'm new to the forum, I'm familiar with primitive bow making, but not laminated bows. I'm attempting something now, but I have a couple of questions.
I've read about "taper rate" and I understand the need for a taper. But I'm not sure what they mean when they say .003 taper rate. is that a difference of .003 of an inch from one end to the other. Or is that a 0.003 difference per set unit length (like per foot or per inch). I'm guessing it's a difference of 0.003 inches every inch of length.
My second question is if there is any way you've heard about tapering laminates without a Drum Sander or other fancy/expensive tools. I'm pretty minimalist with my tools: my most elaborate machine is a small bandsaw. I'm not looking to buy anything right now. It would be nice but I'm just not in the position to do so. I also don't want to buy pre-made laminates either, In my opinion that takes the fun out of making it, plus is more expensive (unless you have to buy a super expensive drum sander). However, I know that it is a viable option for others or myself if I get too frustrated haha.
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The .003 is per inch.
I agree buying the lams may take some fun out, but it will also take a bunch of frustration out. There are several ways to grind your own, but most will require you having a sled or at least one lam that is already tapered. A sanding drum in a drill press is probably the simplist.
Check out kennym, a sponsor on here. I think you will find buying the lams will save you money over investing in specialty tools.
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Bvas................. I was looking for KennyM in the sponsors list and he isn't listed there any longer.
I have built several bows recently with no taper and they all shot very good. Do a search, I think there was a thread on bows with no taper a few weeks ago.
James
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James, since I don’t sell bows, only parts , I am only an associate sponsor . My site is on every post I make tho... :)
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Brad pretty well covered your questions, and I'd be happy to help you any way I can!
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Gfugal, I understand your dilemma. I felt the same way when I started making glass bows. I didn't have the means to grind my own lams, but simply ordering them as random 'parts' to assemble lacked a sense of connection for me. I needed to be more involved.
What I did was use my own lumber, but more often cut my own trees, split and dry them, saw them into lumber, specifically orient them to take advantage of the wood grain the way I wanted, then cut them into oversized rough sawn lams on my bandsaw (the only big power tool I had), and send them out to be ground to my specifications. Back then, I would usually send them to Old Master Crafters, instructing them exactly how I wanted them ground. It was pretty cheap to have them done that way. They just charged a flat rate for shop time and shipping. I'd order glass from them at the same time, sometimes a riser piece, and it would come back ready to glue up.
I'm guessing Kenny could do the same thing for you. Or I could do the grinding for you. Just a few more options for ya if you'd like to have more personally invested.
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I should clarify, it wouldn't come back ready to glue up, not quite. I still had to butt join the lams and work the fades down on the riser... but you get the point.
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"What I did was use my own lumber, but more often cut my own trees, split and dry them, saw them into lumber, specifically orient them to take advantage of the wood grain the way I wanted, then cut them into oversized rough sawn lams on my bandsaw (the only big power tool I had), and send them out to be ground to my specifications."
Jeff, you remind me of an article I read once about "Camper Green". Camper Green was the guy that chimed in last about what to bring on a camping trip. One guy claims the steaks, one the potatoes, one guy the veggies....
Camper Green answered with "I'll bring the stove, the tent, the sleeping bags, cots, pillows, stove fuel... etc. etc."
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Thanks for the replies guys! Maybe I could get a drill press and make a sanding drum out of it one day. For now, I'll see if I can make this one with no taper. I might hit Kenny up for my next stuff if anything just so I have a tapered one as a templet. His stuff is considerably cheaper.
I realized I had another question though. What is a power lam? is it wood, fiberglass, or something else entirely and why is it any different from any other lam.
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Check out the vocabulary thread(second thread). You’ll find about as good a definition as any.
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I put a fiberglass powerlam in most of my bows. I believe it helps take pressure off, and protect the riser fades.
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Originally posted by Bvas:
Check out the vocabulary thread(second thread). You’ll find about as good a definition as any.
Cool Just read through it. I pretty much knew everything on there but my two terminology questions: Taper rate, and Power Lam.
So speaking of power lam what's a common dimension for one. Like how thick is the butt end, when does it start tapering, and how far past the riser fade does it usually go.
I also encountered another term on here that wasn't on the vocab thread: tip wedge. Is that a lam that is placed at the tips to increase its thickness there to avoid whip tiller?
Sorry for all the questions. Just trying to get caught up on what everyone is talking about.
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Originally posted by gfugal:
So speaking of power lam what's a common dimension for one. Like how thick is the butt end, when does it start tapering, and how far past the riser fade does it usually go.
I also encountered another term on here that wasn't on the vocab thread: tip wedge. Is that a lam that is placed at the tips to increase its thickness there to avoid whip tiller?
Sorry for all the questions. Just trying to get caught up on what everyone is talking about.
Can’t say what’s “common”. But I usually use .040 glass and taper the ends at a rate of .006-.008. I usually let it extend past the riser 1-2”.
My tip wedges are usually around 6” long with the same .006-.008 taper. And yes, they are used to stiffen the tips.
Neither power lams or tip wedges are a necessity. But they can be used as tools to get a bow bending where, or where you don’t want it to.
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""Neither power lams or tip wedges are a necessity. But they can be used as tools to get a bow bending where, or where you don’t want it to.""
This is a very good asssessment! And its fun to see what they change... LOL
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How do you keep the tip wedges sandwiched in there without it being spat out by the pressure of the clamps?
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I make a “superlam” that has both p lam and t wedge built into a .001” taper that I use on my bows a lot. Better string angle and maybe a couple FPS . Bends the limb s bit more in midlimb.
On the other tip wedges I’ve used , figure where the end of a lam and end of the wedge is and use tape folded over the ends . Make sure it will be cut off with limb tip tho.
I think somebody said leave em a little long and use a dab of superglue at the ends . But make sure to have bow glue where it will be in limb. I haven’t tried that yet.
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So where do you put the power lam in the stack? Right under the riser, or between the fiberglass backing and the outer lam?
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If I were doing it in separate pcs instead of built into the lam I would put it just under glass unless you were using veneers and clear , then under veneer.
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I have all the shop equipment to grind my own lams but chose to buy mine from Kenny figuring there is a big enough learning curve to deal with making my first glass bow and can learn to grind later , Im glad I did so I concentrated my limited time on form making, footed riser glue up and shaping , hot box making etc , I think $$ VS time buying them is the least path of resitence for a first time maker. at least for me it is.
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Originally posted by kennym:
If I were doing it in separate pcs instead of built into the lam I would put it just under glass unless you were using veneers and clear , then under veneer.
Do you make custom "super-lams", or would you have to buy 4 separate tapered lams to make two tip wedges and both sides of the power lam?
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I have one S/L sled, it has a power lam built in the butt end of a .001 taper and a tip wedge on the other end, both about 11" long. Some of the tip wedge cuts off with the lam cut off at tip, and you can cut a little off the butt end to move the bend toward riser if needed...
The power lam would be in 2 pcs unless you skive joined it . The bows I originally made it for were one pc with the belly lams running up the riser ramps and stopping a bit from center of bow.