Trying to make first 3 piece takedown. Glued up first limb yesterday with .002 taper. Gluing up the limb. I guess in my infinate wisdom (LACK OF PAYING ATTENTION), I unknowingly decided it would be better to reverse my taper yesterday on the first limb. Any Idea what this will do to draw and performance. I'm guessing a lot of poundage loss and really bendy at limb wedge?
I agree it will be very weak at fades and may be killer handshock. I think I'd get the stuff to match other limb if possible .
Well I guess I should have waited. That was actually the first limb. I just finished gluing up the second one to match the first mistake. Figured at least they would be matching reverse tapers.
At least you'll know how it works ! :thumbsup:
This was supposed to be a test to help figure out poundage. Now that it is reversed tapered I am guessing it will be hard to estimate what it would have been if I did it correctly?
I was hoping Bigfoot would jump on here. I figured with all his testing and bow building he might know poundage loss between a forward or reverse .002 taper.
If you only got one taper it's gonna bend funny may even hinge. If you got two tapers only one reversed then it's parallel. Weight will be off.
Its 1 taper and 1 parallel
Check your pm's I send you an answer.....
but I'll repeat the thoughts here breifly.
Draw weight is secondary to how your limbs bend, and where they store the energy.
Different limb designs are going to react differently to changing taper rates. Typically the forward taper pushes the working section further out on the limbs and takes pressure off the fades. A revers taper will definitely put more pressure on the fades.
But...... There are mitigating circumstances where a reverse taper can help you out too.
The stack height and draw weight will make a difference. For example: with static tip RC limbs torsional stability is a key part of sucsess. Every design has a point where these limbs start getting squirrelly. As you start lowering draw weight the limbs get thinner, and you start loosing stability.
Here is an example... I use an .001 FT on my RC design with long lean wedges on limbs 45# and up. Once I go below that draw weight I shift to a parallel down to 35#, and below 35# I use a .001 reverse taper and often use a bias weave carbon on the back to help keep it stable. Once that limb thickness goes below .190 at the base of the curl, it starts gettin* squirrelly.
With an .002 reverse taper, she's going to come off the fades pretty hard regardless of draw weight. I don't think you are going to be happy with the results, and it's going to be a crap shoot calculating draw weight with a forward taper comparing these limbs with .002 FT lay up....... Bottom line... you're toast.... Tomato stakes
I kinda gathered that. I was just hoping there would be a way to get something out of it. I guess I got a lesson 😅
Add a lamination to the belly glass that is strong in compression and put enough of a taper to make the bow neutral in taper or back to a .001 FT with a .003 i think. Sand some glass to adhere the wood lam and speculate on thickness, glue it up in your form with your air hose and pressure strip.
As for a weight increase i have no idea how to gauge that but you would be able to trap the back and sand both the back glass and added belly lam if you needed to bring it down some.
If you want more than nothing out of the limbs go for it
Quote from: dbeaver on October 03, 2025, 12:27:03 PMAdd a lamination to the belly glass that is strong in compression and put enough of a taper to make the bow neutral in taper or back to a .001 FT with a .003 i think. Sand some glass to adhere the wood lam and speculate on thickness, glue it up in your form with your air hose and pressure strip.
As for a weight increase i have no idea how to gauge that but you would be able to trap the back and sand both the back glass and added belly lam if you needed to bring it down some.
If you want more than nothing out of the limbs go for it
So.....
Glass
002 RT
Parallel
Glass
003 FT
Glass
?
I think I will just start over rather than waste more glass and do it right
That's probably the best plan..... but I'd go ahead and finish balancing out those limbs and see what they do... you might be surprised.... Kirk
Quote from: Kirkll on October 04, 2025, 12:08:43 AMThat's probably the best plan..... but I'd go ahead and finish balancing out those limbs and see what they do... you might be surprised.... Kirk
I started profiling them like a recurve. Last 10 inches it narrows. Figure it will help with stability and poundage, I can always reprofile like a longbow later
In my suggestion it would just be one wood taper just to clarify i know you began shaping. I draw from the fact that trilam and quad lam all wood bows have thin laminates as the belly or part of the stack and without any glass. it would be superficial to adjust where the bend is and i believe thin enough to hold up glue directly to glass. There is also an old method of backing a selfbow with glass so open belly wood has a few examples. I thought it would be the easiest way to overcome to taper issue. But also i doubt optimal.
Quote from: dbeaver on October 04, 2025, 05:09:44 PMIn my suggestion it would just be one wood taper just to clarify i know you began shaping. I draw from the fact that trilam and quad lam all wood bows have thin laminates as the belly or part of the stack and without any glass. it would be superficial to adjust where the bend is and i believe thin enough to hold up glue directly to glass. There is also an old method of backing a selfbow with glass so open belly wood has a few examples. I thought it would be the easiest way to overcome to taper issue. But also i doubt optimal.
That would be a cool look. A fiberglass bow with a wood belly as long as the back glass didn't overpower the belly wood.
Quote from: Watsonjay on October 05, 2025, 10:20:15 AMQuote from: dbeaver on October 04, 2025, 05:09:44 PMIn my suggestion it would just be one wood taper just to clarify i know you began shaping. I draw from the fact that trilam and quad lam all wood bows have thin laminates as the belly or part of the stack and without any glass. it would be superficial to adjust where the bend is and i believe thin enough to hold up glue directly to glass. There is also an old method of backing a selfbow with glass so open belly wood has a few examples. I thought it would be the easiest way to overcome to taper issue. But also i doubt optimal.
That would be a cool look. A fiberglass bow with a wood belly as long as the back glass didn't overpower the belly wood.
Only problem is.... That it won't hold up. The compression will most likely delaminate that wood over glass on the belly side. And... if you try it on the back of the limbs you better run it full length and I'd probably use bamboo.
Honestly.... I don't think I'd waste time or materials on it. Just finish them as is, and move on. Kirk
Kirk is right on. I was acquainted with a guy who tried over and over. Always wood with a glass back. They always broke regardless of the wood he used. Tried to explain it to him but his brain was stuck.....or something 🤔
I was theorizing so id stick with the wisdom from experience here and ditch the limbs.
I plan on profiling them just to learn a little but yes I will be starting over im sure. Maybe the will be good enough for a kids bow. Ill probably profile lkke a recurve see how the bend an poundage then maybe reprofile to longbow and see the changes. I didn't put enough curve in the limb form anyway.
Pic of normal longbow in front of this one. You can see how flat the 3-piece limbs are
I think you are going to like that flat section.. :thumbsup:
Quote from: Kirkll on October 07, 2025, 08:44:49 PMI think you are going to like that flat section.. :thumbsup:
I guess we will see....you'd know better than me.
Quote from: Watsonjay on October 08, 2025, 09:59:56 PMQuote from: Kirkll on October 07, 2025, 08:44:49 PMI think you are going to like that flat section.. :thumbsup:
I guess we will see....you'd know better than me.
You will be able to use a thicker stack and have better vertical stability with that flat spot, and using a tip wedge will shorten the working section. Use long lean butt wedges, an .003 FT with a straight taper narrow width profile. It's got good potential .
Quote from: Kirkll on October 09, 2025, 09:35:56 AMQuote from: Watsonjay on October 08, 2025, 09:59:56 PMQuote from: Kirkll on October 07, 2025, 08:44:49 PMI think you are going to like that flat section.. :thumbsup:
I guess we will see....you'd know better than me.
You will be able to use a thicker stack and have better vertical stability with that flat spot, and using a tip wedge will shorten the working section. Use long lean butt wedges, an .003 FT with a straight taper narrow width profile. It's got good potential .
It does have about a 5" tip wedge. We will see
I will be interesting your thoughts of the two different limb designs once yo7 have tested it and run it through the paces. Have you set up a shooting machine and a tiller tree where you can do DFC charts?
Quote from: Kirkll on October 09, 2025, 07:00:26 PMI will be interesting your thoughts of the two different limb designs once yo7 have tested it and run it through the paces. Have you set up a shooting machine and a tiller tree where you can do DFC charts?
I dont have a shooting machine but I do have a draw board