Limb Twist Improvements minimal... next step?

[bowhunter15]

I shaved down the strong side of the belly on one of the limbs until the calipers showed roughly the same on each side. It perhaps looks a little better in the twist department, but not perfect by any means. Last night I took a wrench with enough weight to correct the curve and hung it off the side of the bow overnight. When I took the weights off this morning, the bow relaxed into a little twist.

Should my next steps be to tiller the other limb to match, and just exercise the bow in hopes that it comes more into alignment? Or should I continue to thin the belly on the strong side at mid limb, even if it made that side thinner? Or should I start shaving from the side of the limb at mid limb and not touch the belly?

[Jomohr84]

I always try to tiller out any twist. The first time I had twist I actually scraped the wrong sides of the limbs and made it worse, before I found this thread on   Limb twist  

Once I fixed the twist, my bow that was going to be 50# ended up at 40#!

[bowhunter15]

Yea I started out at 64#. Shot it for almost a year just ignoring the twist. Then I tapered the width on the last 10" so the tips are 0.4" wide instead of 0.66" to reduce hand shock and such. That should reduce poundage. And with the extra wood I'm taking off for fixing the twist, it might be in the 40s or 50s and that's fine.

It is a R/D design so the limbs are a bit goofy to look at. I should probably post a pic to make sure I'm doing it right.

[Roy from Pa]

Either continue to thin the strong side and or check the string nock depths. Are the limbs straight with the bow unstrung?

 

[bowhunter15]

Here we go. Tried to get a telling photograph. So, according to this image and the picture Roy posted, my bow is like the sketch on the left, and I need to remove wood from the belly on the right side of the bow, correct? That's what I've been doing, and as I look at this picture, it does appear better than when I started.

But one thing I would like to know is whether or not I should expect immediate results after shaving the correct amount, or if I need to shave, then retiller to full draw and exercising the limbs gradually pull the bow back into alignment?

[Roy from Pa]

Not sure on the picture, but that bow is unstrung, correct? And are there string nocks cut in the tips? If that bow limb is twisted while unstrung, then the limb is twisted side to side.

[bowhunter15]

Yes, the bow is unstrung, and string grooves are cut in, but there is no string. The limb tip appears to be twisted to the side when looking straight down, but when you take a wrench on the deepest part of the curve and twist the limb (counterclockwise while looking at that photo) it pulls everything into alignment.

[Roy from Pa]

I'd put that wrench back on there and lock it down tight to something so it holds the limb straight. Actually I would lock it down a little wee bit past it being straight. Then heat the entire limb till pretty warm, then let it cool completely. Or if you can see a certain spot where the twist seems to be centered, then just heat that spot while clamped a little past straight.

[bowhunter15]

Alright, I'll try out out with a hair dryer. The garage is about 39 degrees so it should have no problem cooling off afterwards.

[Roy from Pa]

Gonna need a heat gun most likely. Unless ya got a really hot hair dryer..  

[Crooked Stic]

Most times on a glass backed recurve you just need to deepen the string groove on the side that will bring it toward center. So on the initial profile of the limb needs to be left some wider than you want to end up with. Then when you get the grooves right do the final width.

[bowhunter15]

Seems to be getting better with the heat gun. I've done a couple rounds. I'll do another couple tomorrow and see if that does it. Once I get them pretty much straight I can start working on the re-tiller.

[mikkekeswick]

Are you trying to straighten that limb because the string is off the side of your handle when braced?

If so you can save yourself all the hassle when you make another by simply leaving the handle area full width until the bow is braced....then you simply shape the handle to the string. Works everytime on even the most wonky of character staves.

Unstrung pictures don't really mean a great deal. It's what it looks like braced that matters.

[George Tsoukalas]

I would not worry about the twist in that picture.
Are there other problems like string alignment?
Jawge

[bowhunter15]

Here are some more pics while strung:

 
 
 

I can hold it so that the string is aligned down the center, but the curves are outside of the line. When I line up the two tips, the string is off center since both tips bend to the same side of the bow.

[Roy from Pa]

When we say remove wood from the side, we mean at an angle like you do facets, and lowering the facets, not at a 90 degree like you have.

[bowhunter15]

So instead of removing wood like the sketches on the left, I should be removing wood like the sketches on the right?

 
 

[Roy from Pa]

Remove it at an angle like the top picture, with the top being the back of the bow. When the bow is done it should resemble the bottom picture.

I noticed many scratches in the bamboo on the back of your bow, that is not good and asking for a splinter to pop up.

[Roy from Pa]

Read through this thread below.

 http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=2;t=000122

[bowhunter15]

Originally posted by Roy from Pa:
 

Remove it at an angle like the top picture, with the top being the back of the bow. When the bow is done it should resemble the bottom picture.

I noticed many scratches in the bamboo on the back of your bow, that is not good and asking for a splinter to pop up.

So I want to take more off the back than the belly? As if I were trapping the bamboo? I'm not trying to round out all the edges, only just what is needed to bring everything back in line.