Questions about how to finish bow

[Dweena]

Hi, I'm a newbie!
 
I've been pursuing target archery since December of last year. I've been shooting a commercial recurve bow, but I am very interested in shooting barebow.

I got myself a vintage longbow, which unexpectedly blew up in my face on about the 80th draw. That made me sad, because I was really enjoying shooting that thing. So I ordered a very basic longbow from Philip Silva (which turned out to come from rudderbows.com). I had to order a custom one because I am only able to draw about 20 - 22 lbs, which was way below the lowest draw weight they had in stock.

That arrived, and I started shooting it; but the hand shock was such that I started getting tendonitis in my bow hand. Even though I added a padded wrap, it was still hurting me, so I set it aside for the time being.

I am now in the middle of tillering my first bow. I decided to try to make a board bow, found a pretty good red oak board at the hardware store, and just jumped in. I backed it with linen, added extra wood to the grip so it would give less hand shock...all seemed not bad, until I got to the tillering - surprise, surprise!

I built a tillering tree and made a (crude) tillering gizmo. I'm in the long string tillering stage right now and I don't know if I'll ever be able to shave this thing down to a reasonable draw weight for myself. With the long string I can draw it, but I don't imagine that once I get the bowstring on it, that I'll be able to.

My question: how do I figure out what draw weight the bow is currently at? I see people attaching scales of some kind to the string? How is that done? I looked for more detail on George's website but couldn't find the detail I wanted about how he is actually using the scale.
I'm attaching a picture of where I was at with it last night, 18" with the long string:


I would welcome feedback on how to get this down to around 22lb draw weight, and also anything you see in the tiller shown here.
Thanks,
Dweena

[bubby]

Dweena congrats on starting your bow although you would probably get more help in the bow section.
First off you need to shorten the string so that it is at a couple inches brace height then post a pic of it at brace, also needed are the dimensions of the bow length and layout and I'll help you out

[aaron]

Yes, first shorten that long string as much as possible.
next, get a bathroom scale. Put your tillering tree right on the scale and pull down on the string until the scale reads 20. Never pull the bow past 20 lbs. Re-read that last sentence. Just continue tillering until you can get a short string on it. Your tiller looks fine so far. Please post dimentions, a picture of the back, and a closeup side view of the handle. What tools do you have?

[aaron]

Also, you can reduce the handshock in the other bow by narrowing the tips. If you start another thread on it, we can help. On a 20 lb bow, the tips are often no bigger than a pencil

[Dweena]

OK, I will shorten that long string and post new pics of it with a couple inches brace height.

The bow is 68" in length, and is a pyramid board bow. Here is a pic of the belly to give you an idea of the outline.


At this point the board thickness right past the handle fade is .5", and at the tips it is .25".
The limbs are 2" at the widest point, handle is about 6" if you include the 'shoulders' of the pyramids.

And I think I get what you're saying Aaron - but, would it be best to put the tillering tree & bow on the scale first, zero it out, then see how far the string goes to make 20 lb?

Should I ask the admin to move this to Bows?  I promise that's the last question for now!

[Dweena]

Oh, also - the tools I have are: table saw, bandsaw, farrier rasp, surform rasp, chisels, sandpaper, clamps, drills, the usual - the thing I wish I had but don't is a belt sander

[bubby]

You need to start narrowing the width, side tillering

[DC]

Questions are what keeps this place going. Never stop asking.

[aaron]

Yes, zero the scale with everything on it
Can you post a side view of the handle and fades?

[Dweena]

Ugh, I hate posting these - it looks so wonky. But here you go, hope these help:





The darker wood on the handle is Koa.
I don't have a half round file, and I haven't been able to get the rough marks out yet...it looks rough, and is rough, I guess .

[Dweena]

So, side tillering - need to take material off the edges, then? This will reduce the draw weight?
That seems like it might not be too hard. I still need to put the shorter string on this and use the scale. Probably tomorrow - I'm supposed to be getting ready to have people over

[aaron]

Ok, thanks. The fades are a bit abrupt.Next time extend the fades a little, and make the belly surface of the fade more concave. To remove those tool marks, wrap rough sand paper around something round.

[aaron]

Yes, side tillering is removal from the edges, making it narrower.

[bubby]

That looks thicker than 1/4" thick if it is you can still remove belly wood you need to get a more curved transition at the fades

[Dweena]

OK, sounds like the fade from built-up handle to limb should be concave, rather than convex, which is what it's like now -  I think I can do something about that.

The limb thickness is 1/2" right past the fade, so I can still remove belly wood, especially on the lower half of the limbs.

I wish now that I hadn't backed it already - will the linen be a problem when I go to rasping the edges to make it narrower? How would you approach that - would you just mark a line to the inside of the current edge, and rasp down to that?

I'm guessing that I will want to narrow the limbs mostly on the lower half - the top half of the limbs is already pretty slender. So just establish a new angle that eventually joins the existing line of the upper limb, maybe. Should I be working in 1/8" increments to do that, or is that too much?

I strung the bow with a shorter string, enough to give it about a 2" brace height:




And I weighed the tillering tree with bow on it, made note of weight, then  pulled until the scale read 20. However, I think that counts as 14.5 pounds, because the tree/bow weighed 6.4 pounds. I didn't feel I could safely pull it further than that, so I stopped there. This was at 18" draw as given on the tillering tree.


(edited to add) My draw length is about 26.5, so I have a way to go to get where I can use this bow.