$@!&$! Limb twist! (FD pg 2)

[bubbles]

Getting a bit frustrated with limb twist lately.  It is a problem I deal with on most of my bows, both backed and stave. Same problem.  Top limb twisting towards the camera(I think) and probably the bottom doing the opposite. I posted something similar on the "mechanics of limb twist" sticky, but there was no replies.  I've been over that thread dozens of times and I think I'm understanding it correctly, but i just never seem to be able to get a limb from twisting on me.   It seems to be getting real bad on this guy, so I'm reaching out. Which side is the weak side? I'm  kind of at a loss.
I've been scraping what I believe to be the strong side, but it just doesn't seem to be getting worse or better.  There is twist on the tree as well as in the hand and  There is some grain runoff, so maybe that is making the problem worse. I don't want to make it worse at this point. Let me know your thoughts.

[bradsmith2010]

i have read that thread too, I think I am dyslexic about that twist thing,, I am looking at your bow,, if it is twisting to the weak side, that would be the left side in the photo,, so taking off wood in the right strong side would bring the string to center ?? I am hoping someone definitive will post,,,, but thats my guess,,

[DC]

Like you I've read that post many times and walk away scratching my head. There are two main posters there and to me it seems like they are saying opposite things. I'm probably wrong. I've had a few that, like Bubbles, just did not seem to respond. All they did was get weaker. Wizardgoat set me on the road. For that bow I would heat it at the base of the recurve and bend it to the right to bring it into line. Pretty much ignore what it looks like unbraced. Marc St Louis also told me to just grab it by the handle in the vice, pull it to about 20", and manually twist it, no heat, in the desired direction. It's kind of scary but it works.. I think the bottom line is if it dosen't seem to respond to a few scrapes then just be the boss and twist the damn thing

[PatM]

  Go manual on it. Clamp the handle and wrench the recurve past straight. You have to train it a bit
  The scraping of the opposite side it is twisting toward is pretty straightforward but you still have to educate the wood after it's had it's own way for a while.
   

[bubbles]

The twist increases as its drawn though. Is that just a result of the recurve being slightly out of line?

[PatM]

Yes, the recurve gains mechanical advantage on the twist as the limb advances.

[bradsmith2010]

i have to admit,, I have usually gone manual,, heating and twisting into line,,, I have never tried without heat,, but good to know that is an option,,

[BowEd]

Yep the little I know and have had success with is that your alignment is just off a little bit but know that's the trouble here.You got opposing tip alignment there and maybe each might have to be tweaked just a little.Your very close though.

[bubbles]

I guess I was trying to fix it by scraping when I should have fixed  the alignment from the get-go.

[DC]

You fell into the same trap I did. Every time you open the "Bows" page there it is, top of the page, "Mechanics of Bow Twisting". So where you going to go when your bow is twisted? It's subliminal advertising at work

[simson]

Why do you scrape to correct string alignment or lever offset?
I wouldn't do that, take the heat gun and correct your stave! scraping only on one side of the belly produces a 'trapezoid' shaped cross section with different amount of stress on the left and the right side.

I have made lots of statics and most of them have a lever offset when first bracing. I do immediately unbrace and go to correct with heatgun or steam.

[bubby]

The limb twist 4est explained was not a recurve but a flatbow with one side thicker than the other if i remember right

[bubbles]

Right. I'm in the process of getting them in line through gentle use of heat as well as brute manipulation. Its a backed bow so I need to be careful with my heating.   Is it possible that recurves might be a different beast that the "mechanics of limb twisting explained" thread would not apply to? Maybe I should get a pine slat, recurve it and try it out myself.

[George Tsoukalas]

You got some funky grain there in the foreground.

That grain would cause twist that may never come out.


Regarding twist...the weak sides is the side closest to the string at brace. Remove wood from the other side. Use a scraper. Take a few passes...say 10. Take  some really short draws and continue.

More on my site.

http://traditionalarchery101.com/

Jawge

[bubbles]

I feel like the limb closest the to string at brace  is the strong side, at least that's what I understand from the limb twist thread.  Am I wrong on that? It twists towards the weak side bringing the strong side closer to the string?
Anyways,  here is the alignment now and a draw pic. No real improvement on the twist.