Amateur hour: A question about wood

[BowsAreFUN]

Hello!

New guy here. I'm starting on a reflex/deflex hickory backed ipe bow. My previous (and only) build was from a longbow from kit purchased online, so i didn't have to choose the wood myself. I know from what i read that the backing wood grain need to be straight, without run off or knot. I don't know much about sawing techniques, but it seems to me that what i want in that case would be a quarter sawn hickory plank. Does that make sense to anyone else?

Also, how important is the cut and grain straightness of the ipe plank? I have seen a couple of builds online using a 1"x6"x7' decking plank and dividing it to make multiple bows, apparently without regards to wood grain or run off. I don't want to screw up the very first step and having the bow breaking in my face after hours of work.

I'm aiming for around #50 at 29".

Thanks!

[KellyG]

Belly is not as important as the back and hickory does what it wants. So post pics so the experts can further help your cause.

[BowsAreFUN]

I don't have any pics since I wanted to understand what I needed to get before going to the wood shop. I looked online at types of planks and saw this page (http://blog.carbideprocessors.com/uncategorized/quarter-sawn-lumber-vs-plain-sawn-lumber/).

Now I'm just confused because some things I read seems to say that you need the back of the bow to be one growth ring (or is that only for selfbows?), therefore a plain sawn. If I DON'T need the plank to be parallel to the growth rings, then I can get quarter sawn or rift sawn planks with really straight grain, right?

[Roy from Pa]

You want 1/4 sawn for the backing, with very little or no runs outs. 1/4 sawn for the belly works good too with little or no runs outs.

[Bowjunkie]

Yes, the one growth ring deal is mostly for selfbows. Backing a piece of ipe is best done with quarter or rift sawn hickory with virtually no runout of the growth rings.

[BowsAreFUN]

Thanks everyone for the help. Most of the reflex/deflex builds I saw online seems to go for a 68" bow with a 28" draw length. My own draw length being around 29.5", I was thinking I should maybe go for a 70" bow. What do you guys think?

[LittleBen]

With a reflex deflex bow, you could probably go as short as 66" comfortably. I don't think 70" is necessary unless you just want it that length.

Certainly shorter than 66" is possible, but it makes tillering more challenging the shorter you go. Obviously longer is always ok.

[KellyG]

Oh and PM the crap out of Roy their are few that do as many backed bows as he does. even though he is a step closer to glass ones.

[canopyboy]

Originally posted by KellyG:
Oh and PM the crap out of Roy their are few that do as many backed bows as he does. even though he is a step closer to glass ones.

Glass/Grass: about the same at this point. Heck, they're even spelled about the same...

[BowsAreFUN]

Alright, here's the plan:

 

Please feel free to express your amazement at my awesomes Paint skills! The goal here is to get a length of 70" nock to nock and around 50# at 29" r/d bow. Anything obviously wrong in there?

[BMorv]

I've done 3 Ipe/Bamboo bows.  I've never worked with hickory as a backing though.  I don't see any problems with your bow dimensions as they are pretty close to what I ended up going with, and I also have a 29.5" draw.  One thing I will mention with you being a beginner (As am I) is that adding that reflex/deflex adds a lot more difficulty.  You can't use a tillering gizmo with this style bow.  I had 2 bows fail on me because I took too much wood off of the reflex area, so keep that in mind if you do decide to try the reflex/deflex.  
Ipe is a diffuse porous wood, meaning that it is growing all year in its tropic environment, and the wood is dense throughout, so grain orientation isn't as important as in other woods.    That being said, it doesn't perform well in tension, so I would leave the Ipe 1.25" until after you glue in the backing and reflex/deflex. I had one break on me during the glue up stage, and since then I leave it full width (from the top view) and I haven't had any problems.

[BowsAreFUN]

Won't leaving the full width until after the bend make it a lot harder to taper? I'm a lot more scared of screwing up the tapering once the glue is done and the bend is set than doing it while everyting is separated and still flat.

[BMorv]

I'm not sure you are understanding what I'm suggesting.  On your side view, you would taper the Ipe from 1/2" to 1/4" as shown before glue up.  This critical taper would be difficult to get correct after gluing in bends.  
 
The part that I'm suggesting you leave 1.25" is on your top view and only on the ipe. Have your backing tapered per your top view drawing, 1.25" on the handle area down to 5/8" at the tips.  Once you have it glued up, it's easy to follow the backing and trim the remaining ipe.  

Sam Harper has an excellent build along on his website for a reflex/deflex bamboo/ipe bow.  He also leaves the ipe full "top view" width until after glue up.

[macbow]

Agree with BMorv leave the IPE full width shape the hickory, glue it up to your R/D then clean it and use the hickory as a pattern to cut the IPE.