T/D recurve help-along

[Balding Kansan]

Gents - I’m planning to build a TD recurve. I’ve got a handful of self bows under my belt. It’ll be my first glass bow. I know, I shouldn’t start with this but it’ll be ok, I’ve got it pretty well worked out in my head. Spent a couple weeks discussing the materials with Kenny M. and he was very helpful during the process without me having a plan. Other than Kenny’s experience, I’m flying blind here. Stopped by my dads today and traced out 3 of his recurves on some Masonite to get a general idea. 1 is a fedora, another a lost nation, and the last is a bear Kodiak. Just to get a general idea. Anyway, I started my riser layout. I ended up with 25 degree limb pads. The Limb tips are inline with the deepest part of the grip. I obtained my curves by taking a limb off an old target recurve I had a baling wired it up reverse to a steeper curve (don’t laugh we use wire for everything here). So there’s the backstory. I will post pictures along the way. Maybe it will help somebody else out from start to finish. If you see me doing something stupid or have a better idea, please let me know. At this point, with what I have sketched out, I’m worried I’ll have a really high brace height with 25 degree pads, didn’t sound right. Any input is appreciated, this will take awhile. I don’t have forms made yet and need to acquire a belt sander. The plan is to be shooting it by Oct and comfortable shooting it by peak deer season.

[kennym]

Sorry I did t get this info to you sooner! The recurve I have had a 19’ riser pad angle

[Crooked Stic]

I think your pad angle can be flatter with that limb or more setback on your limb. And dont use too much working limb. Use stable core. And under 40 lb. you may want no forward taper.

[Balding Kansan]

Ok. So flatten the pads out a little.

I don’t have stabilcore so should I make the limbs less aggressive?

Also, am I correct in thinking that the more I keep the limb tips behind the handle the more stable it will be? With the trade off being lost performance?

[kennym]

I wouldn't move the nocks behind the riser back.  You need some preload to help performance and make it quieter.  It's a balancing act...

I have stabilcore, but you would need to reduce thickness by .015 or end up heavy(which can happen anyway on a first bow guess)

If you want it, I can make a set of lams that much thinner .

[Buemaker]

Depends of course on design, but on my take down recurves the the string nocks are 1,5 inches in front of back of handle. That is making a straight line between nocks. 62 inch recurve.

[Buemaker]

Like this

[Balding Kansan]

This is all good stuff guys, thanks a lot!

I’m back to the drawing board this morning with these pointers.

Lemme ask you guys this, is the stabilcore for torsional stability? If I don’t use it, would I need to make some more gentle hooks? How did the bowyers of the past get around this? Wider limbs?

[kennym]

Yes on the s core , but there were a lot of them built before they made it...

Is that your curve in second pic?

[Balding Kansan]

I see. The 2nd picture is an old target recurve limb that I pulled into a steeper recurve with some wire. Just to trace and get some ideas.

[Balding Kansan]

Here’s attempt #2. The white block is the same measurements of my riser block.
20 degree pads. Knocks are 1 1/2” beyond the back. Bue’s limb shape is flatter leading up to the hooks, mine somewhat hook the whole way. Not sure if this is good or bad.

[kennym]

I can't answer that, hope some recurvists will come along!!

[Mad Max]

how long is it going to be from nock to nock?
how long is the riser going to be?
how long from the end of the riser is the wedge going to extend?
Buemakers bow looks like a 1950's style recurve. that's a good thing no stable kore back then--1-3/4"  wide glass

[kennym]

There’s ya some help , finally back home?

[Balding Kansan]

how long is it going to be from nock to nock?
how long is the riser going to be?
how long from the end of the riser is the wedge going to extend?
Buemakers bow looks like a 1950's style recurve. that's a good thing no stable kore back then--1-3/4"  wide glass

Nock to nock is 59 1/2”. I came up with this because I’m aiming for 64”. A fedora recurve I was studying is 62” and it measures 57 1/2” Nock to nock, so I added an inch to each end.

The riser is 19” long

I was planning on 3” of bearing surface on the limb pads. Kenny cut the wedges at 10”, so I guess I would have 7” hanging out past the riser end.

[Mad Max]

How are you measuring the nock to nock?  Unbraced or Braced?
like this <-----------------------> or along the back of the bow

[Balding Kansan]

How are you measuring the nock to nock?  Unbraced or Braced?
like this <-----------------------> or along the back of the bow

Unbraced. Straight shot across. Not following contours. Thanks!

[Mad Max]

#2 looks pretty good.
Edit 19" riser with 18 degree pads, 3-1/2" of taper (0 to 1/4" thick in 3" on the butt wedge) will be a good bow.
Make your pads 4" long, the rest of the wedge is scrap to cut off later.
18" of working limb from the nock to the end of the wedge fade, is good too.
For 1-3/4" glass go to 1-5/8" wide (or even full width 1-3/4") out to 8" from the nock, taper that 8" down to 5/8" wide, NO tip wedge.

Full width may be better to keep down on limb twist.
You need that 18 degree to make the tips open up at full draw.

[Balding Kansan]

#2 looks pretty good.
Edit 19" riser with 18 degree pads, 3-1/2" of taper (0 to 1/4" thick in 3" on the butt wedge) will be a good bow.
Make your pads 4" long, the rest of the wedge is scrap to cut off later.
18" of working limb from the nock to the end of the wedge fade, is good too.
For 1-3/4" glass go to 1-5/8" wide (or even full width 1-3/4") out to 8" from the nock, taper that 8" down to 5/8" wide, NO tip wedge.

Full width may be better to keep down on limb twist.
You need that 18 degree to make the tips open up at full draw.

Thanks a bunch. I’ll redraw.
You lost me just a little though. So the wedge will be 7 1/2” long? 4” on the pad and 3 1/2” tapered down to nothing hanging off of the pad?

I need to start getting some stuff ordered. Hose plugs from big Jim and a belt sander. I was looking at the rigid belt/spindle sander, but if I ever wanted to pattern sand, how would that work if it’s oscillating?

[Mad Max]

Thanks a bunch. I’ll redraw.
You lost me just a little though. So the wedge will be 7 1/2” long? 4” on the pad and 3 1/2” tapered down to nothing hanging off of the pad?

Yes
leave it long 8-1/2" so you can pin them together, we will go over that later