Another mad project!

[Halfbow]

Wow it's looking much better! What did you do? Tore it apart and added a 3rd lam? Or just started over?

What kind of set is it taking? Are the tips wanting to twist to the side at all? Since it's already so narrow, your only option may be to keep bending it more and watch that it takes even set, and not too much. If it seems stable, could do some minimal tillering on the sides. Why not? Also you can kind of train bamboo. If you want one area to bend more, hold the handle in one hand and the tip of the limb in the other, and repeatedly push your knee in to the belly of the limb where you want it to bend more. But it looks like you might end up with a bow with a shorter draw and higher draw weight than you intended. But it might be a bow! Might even be surprisingly fast.

[MattZA]

Well I shot it a bit today.

Brace height of 3". Drawing 20". It was pulling 28# at that length. Bracing the bow requires a stringer because of the force needed.

It's VERY fast, and surprisingly smooth. I was expecting a lot of handshock, but I'm pleasantly surprised.

You're going to be amazed at what I did to fix it... I simply glued another lam onto the belly. Just like that. Tillered to be stiffer in the handle, cut from the same piece of bamboo.

It's taking a pretty unique set. It's straight before stringing (with the siyahs about 3" in front of the straight line). Then it takes about 2" of set immediately after being unstrung. That set returns to zero after about 5 minutes. I put about 50 arrows through it today, and it is currently straight, like I've never strung it before.

The side twist is also quite strange. It pulls a tad sideways on the tillering stick, but when drawn and fired it tracks pretty true. The lower side occasionally ends up a tiny bit to one side, but nowhere near enough to miss the string bridge. Which I'm very happy with, considering they're just 3/16" wide.

I also haven't heat tempered the belly at all. I'm kind of saving that for my trump card as a tiller. I was considering heating the handle section to make it stiffer.

It's such a disaster to look at though. The belly lam that I glued on was a bit too narrow - so it was entirely unbalanced when dry. To remedy it, I simply carved a couple of pieces of thin bamboo and glued them awkwardly onto the edges. They got a small sanding (which is the extent of my artistic skill), and somehow fixed the balance.

[Halfbow]

Ha! That's great. Who cares what it looks like as long as it works, right? I'd love to see a pic of this belly lam.

It's good that it returns to straight. Bamboo is very resilient. Out of curiosity, during those minutes when it's still showing set, does that set make an even arc?

It sounds like twist isn't a problem but if you want to perfect it and you feel like your siyahs could stand to be a little thinner, the easiest and most effective way I know to fix alignment on a bow like this is to thin the tips on the appropriate side. Just go slow and string it up and check your progress before you feel like you've done enough.

Be careful with heat. What kind of glue did you use? I've ruined more than one laminated bow by trying heat corrections after glue up. Guess I'm a slow learner.

[MattZA]

I've attached a few artistically disgusting, yet functional pics to have a look at. I don't even really sand a bow after a glue up unless it's going to affect the tiller. That said, this is my first ever attempt at actual lamination (across any kind of woodwork discipline).

The set isn't 100% even. It's a tiiiny but more pronounced at the inner limb area

I'm using South Africa's version of TB3. It's named differently, but is made by the same company, and is identical in its makeup. I'm glad you warned me about this. My total "just wing it" approach would love some guidance in that area.

[MattZA]

A few more, showing overall length and various widths...

[MattZA]

Oh, just to mention the glue...

I mixed it with saw dust from a random other piece of wood (a door needed sanding).

So it's a mix of TB3 and doordust 

[DC]

About the twist on the tree and not in the hand. I had this with a bow and what it was in my case was a little flat spot on the handle the held the bow slightly leaned over on the tree. This lean started the bow twisting. When it was in my hand the flat spot had no effect. I rounded the handle to let it rock freely on the tree and the problem went away. This may not be your problem but it was a nice thing to find.

[MattZA]

DC, that was exactly what it was. I added some cushioning to the top of the tiller so the bow would stay in the position I want and it's been perfect since.

What are your thoughts on wrapping them? Do you think it's necessary when we're only playing with about 45# all in (including brace tension, which is substantial).

[DC]

Wrapping them??

[MattZA]

Sorry,

I mean wrapping the siyahs...

[DC]

The only bow I glued siyahs on I used a 3" "V" joint. It was a 40# bow. I didn't wrap them and had no problem. I did notice your joints are short but  it's not a heavy bow. Is it a "V" joint or glued on top?

[MattZA]

It's just a straight forward V splice. You'll also notice the temporary string bridges. I'm going to measure the height of them and carve new ones to match the siyah wood. They'll also be stuck onto the v splice showing on the belly. That'll provide a bit more support too.

The bow is going to be around 40-45# in total, if I include pre-brace tension.

You reckon that'll be enough?

[DC]

I'll take a guess and say that a 2" "V" joint will take it. If you're worried a few wraps of thread will help. I always use epoxy so I don't have any first hand glue advice.

[MattZA]

Yea I was considering a few sisal twine wraps. They bond very well with simple white PVA glue in my experience.

Then it's just to find a way to wrap the entire bow in felt, and build up a handle of some kind...

[Halfbow]

Looking forward to seeing how it turns out. I'm fond of this little bow.