? re: altering a bow's weight

[?ucznik]

#2947

I have a longbow that I purchased a couple years ago that is a wide-limbed D-style bow. I do not remember what kind of wood it is made of but, it is backed with clear glass. It was not an expensive bow. I think I paid $130 for it new. The bow claims to be 55#@26″ but it feels A LOT heavier than my other longbow which is 53#@26″. It also seems to stack quite a bit.

OK so; here are my questions. How difficult/expensive would it be for someone to modify this bow to a lighter draw-weight? Is this something that someone with absolutely no bowyery experience could reasonably accomplish or should it be taken to a professional?

[William Warren]

#14796

I would’nt try it and I have 11 years experience with tillering selfbows. I would take it to someone who is skilled at tillering that type of bow. Assuming they would risk making your bow too weak. Definitely a job for a professional.

[Stephen Graf]

#15280

I have to respectfully disagree with Duncan.

Since you say it is not an expensive bow, and it currently isn’t fun to shoot, what have you got to loose? It would cost you more to have it fixed by a bowyer, then it cost you to buy it…

If you want to learn about making a bow, this would be a good place to start without actually having to make one from scratch. If you aren’t “burning” to make a bow, then skip it.

You can reduce the weight of a glass bow in several ways. They all require a lot of sanding. If you have a belt sander, or palm sander, it would make it easier. But hand sanding, elbow grease, and time, will get you there. I would suggest you get a bow scale if you don’t have one. Otherwise, when checking the bow weight a bunch, you start fooling yourself. It’s also nice to see how much weight is shed with how much sanding. Thus you can predict how much more sanding you need to achieve your goal. Also, a good dust mask is mandatory. Fiberglass dust is hell on your lungs.

– you can narrow the limbs by sanding the sides (is the bow really narrow limbed? then this may not be an option)
– You can sand the belly corners near the riser, and out about 18 inches (makes it trapezoidal in cross section)
– You can sand the back corners near the tip and in about 18 inches. (makes it trapezoidal in cross section)

If it was me, I would do a little of all three, and check the draw weight often to see how things are progressing. After I had gotten within 3 pounds of my draw weight, I would check the tiller, and if necessary sand the belly of whichever limb needed adjusting.

Whew, that sounds like a lot of work 😆

[William Warren]

#15551

After looking at your post again I have to say Steve makes some valid points on all counts. The bow may not be worth paying a bowyer to retiller to a lower poundage and it would be a good learning tool if you want to learn about tillering a bow. As for me, I’m not thrilled about the idea of sanding fiberglass but as Steve stressed, it can be done safely with the proper breathing protection and probably should wear some latex gloves too. Good luck with whatever you decide to do.

[Chris Shelton]

#15606

I think these gentlemen above have said it pretty well. I have very little bowyer experience, all I have done is finished a U-finish bow, so that is not very much. However, I didnt see either of them say this- be careful not to sand one spot more than the others, or the bow will hinge. Expeically when using power tools, with a elbow grease I think you would have to work hard at over sanding a specific spot, but with a belt sander, keep it in one spot for too long and it could effect it! Just my .02

[?ucznik]

#15856

steve graf wrote:
You can reduce the weight of a glass bow in several ways. They all require a lot of sanding.

Oh goodie! Sanding is my “favorite” activity!!!

steve graf wrote:
…a good dust mask is mandatory. Fiberglass dust is hell on your lungs.

I’m assuming I would only be sanding the fiberglass from the sides. Is that correct? I wouldn’t be sanding the fiberglass to be any thinner would I?

steve graf wrote:
is the bow really narrow limbed?

No, quite the opposite actually. It is a profoundly wide-limbed bow.

steve graf wrote:
Whew, that sounds like a lot of work 😆

Oh well. Most things are.

Actually, all things considered, I think I will be time and $$ ahead to just let this bow go. I too am not terribly thrilled about the idea of sanding fiberglass.

[William Warren]

#15979

If it is profoundly wide as you say maybe carefully reducing the width is the way to go.

[Hiram]

#16054

All along the way, you must try to keep your tiller within reason while doing this. Start by marking two points, preferably at even points at the fade outs and measure your tiller. Bet it is positive by a little, say 1/8 to 1/4. Do you shoot split or three under? Split is better with a little positive tiller, generally. Now you have the points measured to check periodically while you sand. Since you are not a Bowyer, I would recomend a sanding block and several grits of sandpaper from 80 on the sides to 120 on the glass. I would narrow the sides all the way to the tips first, evenly as you go and measure often. I would string it from time to time and check for centering too. I would reserve sanding on the back (front of the Bow) primarily for tillering. Use dial calipers for measuring the limb width and go slow! Harder to put material back on than taking it off. Or, better yet, sell it and buy a cheapy in the right draw weight LOL.:)

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