Tillering help on bamboo-IPE

[SOS]

Finally got my first bamboo backed bow on the string and as you can see it is, in my mom's old terminology, "katy-whoomp-us".  Please offer advice on where to go on the upper limb (right) to get it bending.  Wasn't sure if I should keep scraping the whole limb or concentrate on one section more than others.  Thanks for your help before I go whacking away at it.  Steve

Current tiller

 

Unstrung before roughing out the riser.

 

[walkabout]

it looks to me like the portion just about halfway in from the end needs scraped to allow your reflex to bend like the left limb is. inner limb looks fine, you just need to get the outer half of the limb moving a bit more. looks good though.

[SOS]

Thanks Richard....so take 10 or so scrapes of the middle third of the limb, exercise it, then string it up.  Then repeat until it gets close to the same shape and bend.  Then start working them down to target weight together?  I do like the way the lower limb is looking.  Steve

[Roy from Pa]

I would slowly remove a little wood where it is circled. Do maybe 7 - 8 scrapes, then recheck on the tree. Otherwise it looks sweet.

 

[Roy from Pa]

Also check out this thread and make yourself a tillering gizmo. It works great.

  http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=2;t=000075

[walkabout]

yep the area roy outlined was right where i was referring to. the other limb draws out the reflex but the right one doesnt so careful scraping until it comes around. id put a mark to indicate where you want to localize your scraping so you don't end up with hinges. the tillering gizmo roy linked also will help, and it can be made as simple as drilling a block of wood and pushing a pencil through.

[SOS]

Thanks, I thought scraping mid-limb and maybe a little toward the tip was right but this is my first bamboo backed bow, with a little R/D to boot.  Better to ask than be sorry!  I can't wait to get them bending evenly, then I can start moving in on final draw weight.  Cheers, Steve

p.s.  Will the tillering gizmo work on an R/D bow or only on a straight limbed bow?

[walkabout]

the r/d design will allow use of the tillering gizmo. as you can see from the other limb, once braced it looks like the normal profile of any straight limbed bow more or less. some r/d keep their reflex alot until drawn almost full length, however on your bow the other limb is already bending so it would only help to even it out. hope this makes sense.lol

[SOS]

Now we got it in the ball park. Much better - but idiot me took the pictures backwards from earlier....
Here it is strung and pulled to 10 inches.

Time to go slow and work down to the low 40's is my target.

Thanks for your input....
 
 

[walkabout]

looks much better. remember too that you can use thinning the limb width to help get closer to weight and better tiller. helps when you got limbs that are looking thin. tillering gizmo will help alot now, since it can show you areas that you cant see sometimes. in the bottom pic the right limb looks stiff toward the tips and the left limb looks like its bending pretty well out of the fades or a bit from there so be careful of them.

[Stiks-n-Strings]

I was thinking the same thing as Richard, looks a bit stiff yet on right limb in the botom pic. I would give it a few swipes in the last 1/3 of the limb and maybe two or three scrapes in the 1/4 at the fade.

[Apex Predator]

Much better Steve!

[razorsharptokill]

I have a bamboo backed osage and elm that looks like that at long string. I used some scrap from around the shop and some shipping slats KennyM sent. I didnt mic them out well enough I guess and the tiller is WAY off. I may revisit this project now. Maybe there is hope.