"pushing my limits" bow buildalong - Cosmetic suggestions?

[ChrisS]

Hey all. I'm working on a static recurve and I've been documenting my progress. This is a total learning experience for me, since I've only tried building one static (selfbow) and it blew up at 22" of tiller. School will have me busy soon, so I figured I should go all out and try a few ideas that have been swimming around in my head.

Advice, critiques, and bets on how far I get before she blows are all welcome!        :D      

       http://www-personal.umich.edu/~cdsnyder/buildalong/index.html      

Chris

[the Ferret]

Neat Chris. Will be watching intently.

[Osagetree]

Real nice,,, Can't wait for more!

I say you go all the way and it's a real shooter!

[Wallcrawler]

Looking forward to the rest of your build.

[TexMex]

[Deadsmple]

Go Chris! I'm pulling for ya, hope it's a shooter!  

[tom sawyer]

Excellent build-along so far Chris!  How did you bend the hickory tips, same steam process?  And did you flip the hickory backing's glue line with respect to the mulberry so they are not the same orientation?  That would probably be slightly stronger.

Your 6" tips do look long, what would you make them now that you see them?  4"?  And is that 6" counting all the wood in the bend or is it to the middle of the bend?  

Your under-backing lam sounds like a good idea.  Will it be full length or tapered to a knife point at midlimb?

I agree with your prep of the hickory backing, I think it is far safer to taper only the glue side.  Especially since you cut it down so much.  I do wonder whether you needed to thin it that much, I'm not one who thinks a backing can necessarily overpower a belly in the thickness range we are dealing with.  I'm finishing a hickory-backed bulletwood bow and it is nearly half hickory in the outer third of the limbs where there is significant reflex, it has held up quite nicely.  Mulberry is pretty light though, guess you were playing it safe.

Keep up the good work.

[ChrisS]

Thanks all for the encouragement. I didn't get much done yesterday evening or this afternoon. On the plus side, I got the landlord to pay me $50 to clean the gutters for his two houses here     My bow building budget just doubled lol.

Oh, and before I forget again. Here's the one that inspired me to give this a try. My design borrows heavily off his, though with less premiere materials    

  http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=40;t=000028  

Lennie - Not exactly sure on the new length. The 6" was from the start of the bend to the tip. I didn't expect it to look so long, but I've never bent wood around a radius that small before.
The bend only took up 2" on the back face and the remaining 4" are straight out. I may go as low as 2" from where the bend straightens, but I'll have to take another look after it's glued and bending a little.

I did the hickory bend the same way. Steamed them for all of 10 minutes. When I unclamped they were only 45 degrees or so, whereas the mulberry kept a good 70 degrees before the dry heat. After the dry heat, however, the hickory was identical to the mulberry bend at around 80 degrees.

I'm going to try a 17" middle lam. I don't know how much it will stiffen the limb up past the fades. JD went with 2-1/2 inch past each fade so I'll try the same and see what happens.

Yea, I'm playin it safe with the hickory. My selfbows out of this mulberry all took on set pretty easy. It's not the best compression wood, but it's so lightweight. I may have better luck with this since it is quarter sawn from the inside rings which were 1/4" thick. My selfbows were from the rings just inside the sap layer and the rings are very tight there.

I had better get in the basement and back to work    
Chris

[ChrisS]

Ok, updated for tonight. Any last minute tips for the glueup tomorrow evening? If I wrench the midlimb down to 1-1/2" deflex will it relax a bit? My target is 3/4" or 1" of R/D. I don't have a tool for toothing the surfaces. I plan on using a 16 tpi jigsaw blade, good enough?

[tom sawyer]

The jigsaw blade would work, I use a fairly fine hacksaw blade and it works great.  Try and scratch until you see new wood and the shiny stuff is gone.  Maybe a very light sanding with 60 grit prior to scratching would help.

As for glueup, make sure you have evenly distributed pressure with your clamps.  I use small blocks of wood that extend across the entire limb.

I persoanlly think 1-1/2" deflex is a bit much, but taht is just me.  If I have 1" I'm happy.  I use a "2x4 block" method.  I put the tips up on 2x4 blocks standing on their long side (3.5"), so that they hand off just a bit and thi8s give closer to 4" reflex.  Then I clamp the handle to a 2x4 block on its short side (1.5"), then clamp the limbs down a little farther than that on either side, about 1/3 the way out.  This gives me that 1" or a little less of deflex.  I figure the bow will set a bit near the handle and that will accentuate the deflex anyway.

With this approach I've been getting consistent resluts of 1" of net reflex, that means I'm only losing 1.5" in tillering.  More a tetament to the design and backing, than my skill.

One other tip, you are likely to have a lot of squeezeout, so put down some plastic wrap to catch the stuff or you'll have a mess on your hands.

[tom sawyer]

Clamp from the handle area, outwards to make sure the surfaces are mating right.  Less potential for gaps that way.

Oops should've looked at your progress report first, disregard that earlier advice.  And anyway, I wasn't thinking about your tips sticking up that far.

The power lam looks excellent, I'm going to give that a try myself.  I've been putting them on the belly side and they work decent there too, on the backing side it'll give you more natural deflex I suspect.

[ChrisS]

Thanks for the tips Lennie. The glue up went smoothly except for the backing not lining up at the tips. Glad I left the tips at 1" wide, there is still plenty to work with. Having 4 layers to the handle made everything want to float around, but it was worth it. The middle lam appears to have helped the deflex as you said.

I updated pics for tonight. Looks like it turned out ok, pending judgement of the glueline. I have the feeling it is a bit thick.


edit: oops, I forgot to change the server copy. *now* it's updated  

[tom sawyer]

Looks good to me.  I know what you mean about things floating around,with thigns all buttered up the lams want to go every which way.  I clamp mine in the center and work my way out, and even then I generally have to loosen things a time or two to realign.  And you're not supposed to do that but I've always gotten away with it.  I generally do the backing/belly first, then a thin power lam on the belly (just pressed to form), then finally a handle piece shaped to the curve.  Takes three days not one though.

Your wood prep looks right, and your glue lines look fine.  Those glues are good to something like 1/16".  Being off a bit on the backing is shouldn't cause any harm since you left it wide.

I use plastic clamps myself, about the same number as you.  You can get away with fewer if you use blocks to distribute the pressure.  And your tip clamps left something to be desired, you'd have been better off cutting a piece to press the curve uniformly, or use a metal strip and clamp it all along.  But it won't be bending and I bet you'll be lopping some of that off anyway.  Don't mean to be too critical, you are doing a fine job overall.

I shudder to imagine what the tillering of that beast will be like!  Looking forward to YOU doing it and reporting with more good pics.

[tom sawyer]

Another question, what do you envision this bow limb bending like?  Where are you going to shoot to have the string lift off the statics?  I don't see many of them, where in the draw does a Grumley lift off?  Anybody know?

I almost think I'd have put a little more sweeping reflex in the mid-limbs, but that might just make it even more difficult to tiller.

[AkDan]

Good stuff Chris.  HOpefully my urac is still good LOL!
'
Nice kayak too!!  Is that one of the
guillemont (sp)?

[ChrisS]

Yea, I would have sanded down something to put in that curve, except that during the dry run the backing was up against the belly all the way around. That and my impatience actually had me up til 2am that night heh.

1/16 of an inch?? Wow.. here I was worried about mine being too thick. It turned out more or less uniform too.. a little variance here and there.

I would have liked a bit more reflex in there... it kept the deflex and then went flat for some reason. I tend to bite off more than I can chew with my projects, so I'm going to take it one step at a time and decide where to go only when I have to hehe. For now I'm going to get to the final profile and start getting it to bend. For the shape, I guess I'm just going to concentrate on getting it to look like a regular longbow shape and imagine the string as if it were on the static bend instead of the tip. I'd imagine there is a greater stress just before the curves, so I'll leave it thicker until last. I'm just guessing at this point.

Thanks AkDan. So you found a few of my construction pics eh? I suppose you know what my house looks like too now.    Yea, it's a guillemu.. gill... yea, one of those. I started and then my dad joined in to make one for himself. We built em side by side back at his place. Those pics were right after fiberglassing.

[ChrisS]

Ok. Got it tillered to the point of bracing it tonight. What do you guys think? I read somewhere that it's easy to think the inner limbs are moving when they aren't with an R/D, any other things I should keep in mind?

Link to third page:
  buildalong page 3

[Luke Vander Vennen]

Don't have much advice as I've never done a composite bow, but I'm enjoying this  

[ChrisS]

I very much enjoyed yours too Luke. In fact, it was part of the reason I decided to try taking on a bow that would likely be beyond my abilities lol. I wasn't around while you were building, but when reading I couldn't help but smile and think "Oh yes!" when you decided to recurve it  


I fixed the twist and started trying to even out the limbs. I'm going to work the flat spot on the right again tomorrow. I think after that they will be a decent match. *crosses fingers*

Here's a couple of closeups for where I left off. Are there any problems spots that I don't see? Any advice is greatly appreciated. It appears to be moving along ok so far, but I don't have any confidence in myself haha.

 

 

[Shakes.602]

Looks Really Good Chris!! Be Proud of Your Skill and Effort Buddy!!