over shot my weight.. best way to reduce? (updated - now twisting)

[Bradford]

So I was so paranoid of not getting the weight I wanted, I think I overshot.

There is .050 glass in front and .050 glass in back.. the limb is 1 9/16 wide at fade and down to 3/4" at tip.

I know I can sand some off the glass to lower the weight.. but what is the best way to sand the glass with out ruining it..

And is there any other ideas.  

Thanks

[Roy from Pa]

Sand glass off the sides equally on both sides.

[PEARL DRUMS]

I watched a guy named Art from "Art of Archery" bows reduce weight on a bow by about 5#. He did nothing more than reduce the width as Roy mentioned. It didnt take much and I couldnt tell he did it.

[Trux Turning]

How much weight are you needing to reduce? You will get a bigger reduction sanding the glass and with .050 on both sides that should give you at least .010 per side you can sand off. Sanding the sides will also reduce weight but not as much- plus you can run into limb stability issues if you get too narrow.

[Bradford]

That is what I was worried about Trux.. They are already pretty narrow.  I had the guy I am building it for help me string it up this morning and he pulled it back about 26".. said it felt to be about 65#.. so I bet we will be close to 80# at 30".  I was going for 65# at 30".

So I might throw on the 150 grit paper on the spindle sander and sand down the black glass on the belly down .010 or so and see what it does.

I am afraid to sand the clear glass to much.. I don't want to ruin clearity.

[Don Armstrong]

Shouldn't you put it on a scale first? I have a lot of trouble guessing weight. Don

[Trux Turning]

I would go with hand block sanding the glass vs the spindle sander- that way you can take the same amount of strokes off each limb-I would get a weight before the sanding begins also to gauge your progress.

[Bradford]

That is the hard part.  With my arthritis, I could not get the string on it myself.  That is why I brought it with me to work for the guy I am making it for.

He said it felt good till about 26" then started to get harder.  I was watching the side profile and notice it was not bending all that much from end of fade and up a bit.  So either way - no matter what the weight is, I need it to bend more there.  So I will do the block sanding method on it to make it bend a little more in that area and bring it back into work with me so he can string and test it.

[kennym]

Block is much safer!! Too easy to get thin in places with a spindle. I'd count strokes also and make all glass same as close as you can!

[JamesV]

I would retaper the limbs 1 1/4" at the fades down to 1/2" or less at the tips. Then get yourself an orbital sander ( 1/4 sheet) with 80 grit and work the glass down both sides till you get close, then switch to 220 grit and finish the glass. Check yout tiller and weight as you go. With .050 glass and narrowing the limbs you shouldn't have any problems taking 15# off.

James

[strungstick]

You should be able to easily drop 15 lbs with a little patience.  I've done it on a couple of recurves I've over shot the weight on.  Wood block and sand paper is the way to go.  I've seen guys do it with a large pnuematic sanding drum, but I don't have one. Get a bow scale, check your tiller as you go.  Unless you've made a number of recurves I'd keep the width, they can be a little difficult if they get too narrow out at the tips.

[Robertfishes]

I also missed weight on my latest bow..it was a new form this was the first bow off of it. stack was only .243 and it came out 65 lbs a whopping  15#s heavy..I retapered the limbs about 1/16" on each side, had to leave tips wide because of the way tips are bending on tiller string and no tip wedge. I sanded the 040 belly glass mid limb with a sanding block and 180 grit paper,then 220 paper, I then rounded the heck out of the belly glass edges pretty much trapping limbs using a "shoeshine" stroke and 1 inch wide by 24 inch long 120 grit emory cloth then several pieces of 240 grit emory cloth (also 1 " wide x 24 long ), I have a 100 ft roll of each..got it down to 56 lbs. I would not use a spindle sander on the glass, very likely you will get a bunch of thin spots (waves). what ever you do go slow and easy

[Bradford]

Thanks everyone for the advice.. a little bit of everything.. but you gave me the confidence to jump in and do it.

So I did use a block for sanding but I did not count strokes.. instead I marked multiple places and used my micrometer so I knew they were both the same.  Took off about .012 from the black glass on the belly and narrowed up just a bit.

 

 

 

I am at 1 5/8" at the block.. then down to 1 1/2" at the end of the fade.. then 1 3/8", 1 1/4", 7/8" and 3/4" at tip.  These are 4" increments.  I am at .310 at the end of fade.. .295 @ 4" then down to .260 starting into the curve.

I am going to bring it in to work with me and let my buddy string it up and test it again.  I will let you know what happens.

Any more opinions or helpful tips are still welcome.  I am hoping I am not to narrow for stability.

[bamboo]

get a bow stringer--someone posted pictures of stringer that mounted on the end of a bench--a while back---it looked real easy and safe---and guessing the weight--is well..guessing?!??

[Bradford]

I have a bow stringer.. it is still hard for me.
We are measuring 65# at 27"... so by the time I am done sanding we should be good.

I am getting a little limb twist.. but nothing that can not be corrected with a little tweaking.

Here it is being pulled back..

 

[JamesV]

Bradford............

OOPs.........The suggestions I made were for a longbow, The advice from the recurve guys is spot on.

Good luck

[Robertfishes]

I worked on my over weight bow some more. It's a one piece. I still had my pre glue up tape on tne back and I also had a grid on it but in one inch increments, I make the grid and center line pre glue up, I check centerline with eye and string after glue up..last night  I sanded sides fade to tip, I also rounded the edges of belly glass quite a bit.. Limb width at fades is 1 9/16" and tips are a fuzz over 5/8 at string groove. Thats as far as I can go on sides,I can sand the belly glass a little more..but may leave it where its at. You may be able to reduce last 8 inches of limb to tip?

[Bradford]

Yeah.. I can still sand down the clear glass side.. the will give me a little more there.. I still need to round the sides more.. and yes, was going to do the tip area a bit more as well.. He said it pulled back a lot nicer this time.. so a little more should do it.

The scale I have is hard to use on heavy bows.. so he was only able to pull back with the scale to about 26".. and hit the 65#.. so I am guessing that it would be around 75# at 30" because of the power lams.  So a little more work and I think we should be good.

I just have never made limbs so narrow before.. but it seems to be stable.. and reading the post others have gone that small..

[Bradford]

Well.. now I am getting sever twist.. I think it is to narrow

These pics are hard to see it, but when stringing it, the limb bends off to the right

 

 

 

I don't know.  I already started cutting wood up for a new limb.  If I switch the stringer around it does not do it.  So I think I got something off or just went to narrow for too long at the tips.