Stack weight

[Badger]

   As long as the bow can handle the stress the recurves will always add to the speed. Many times a bow will already be over stressed and have taken set so the builder will recurve the tips hoping to offset the set. In this case it backfires and just takes more set.

[DC]

So 26" was the peak. 27 dropped to 173 and 28 was 175. It's taking some serious set, 2-3 inches I guess. So this much bend is too much for OS I think. Maybe 61-62 inches long rather than 57 would be the sweet spot. The recurves aren't very aggressive either. Looks like the bottom limb could have bent a little more. Actually the top limb should have bent a little less. Back to chores

[Stick Bender]

One thing I have always liked about you DC is you put your talk and your ideas in to action rather then just rely on theory because there are times when you build a bow that it performs differently then expected, there is really only one way to find out  & you do it 

[SLIMBOB]

Well said and I agree. Mucho.

[sleek]

I certainly appreciate your willingness to experiment!

I think with the set the bow was taking, any gains or losses from the further draw length and string tip angles will be lost or unobservable due to the set.

[Badger]

  I agree with Stickbender, you are doing some good research work. I used to do a lot more but not as motivated as I was. How much is the mass in that bow and what was the starting reflex?

[DC]

493 grams and it was pretty much straight with a bit of deflex dogleg in each limb. I steamed that out but a bit of it came back. Pic is after sitting for a day. I'm trying to think of kinda the next step. I could reflex the limbs and bring it back to 40# or deflex the handle but deflexing would drop the draw weight and any results would be meaningless. I could do both. Deflex the handle and reflex the limbs trying for the same total reflex as it has now. that may preserve the draw weight. I'll have to decide if it's taken to much set.

Thanks for all the nice thoughts but the motivation is mostly trying to find something to do in the shop that doesn't result in another bow hanging on the wall. There's almost 60 hanging there now and it just starts to feel pointless to make another. The horn bow is taking no daily time, it's mostly waiting.

[silent sniper]

Very nice work DC, thanks for posting!
-Taylor

[DC]

Here's the next step. It's got 5" of reflex and about 5° of deflex. I was trying to get the same reflex as I had before but I over did it. Some will pull out. Tiller seems OK on the long string. See if I can get it braced

[DC]

Got it braced but the string alignment got messed up when I reflexed it. I'm correcting that now. I should have picked a stave with no sideways bend for this. It's coming back to haunt me.

[SLIMBOB]

What?  There is such a thing?

[DC]

OK string alignment is good enough. Put it on the tree and it went to 40#@28 with no tillering. That's the same DW as when it was straight. Most of the 5" reflex pulled out. It now has 1 1/2" total reflex which is very close to what it was when it was straight. It now shoots 181fps@10gpp.
When I pulled it to 28" before I deflexed the handle it was starting to take some serious(I thought) set. I think deflexing took some strain off the bow letting it hold a bit of the reflex I heated in. It was 175fps before so it looks like just changing it to RD got me 6fps.

[sleek]

OK string alignment is good enough. Put it on the tree and it went to 40#@28 with no tillering. That's the same DW as when it was straight. Most of the 5" reflex pulled out. It now has 1 1/2" total reflex which is very close to what it was when it was straight. It now shoots 181fps@10gpp.
When I pulled it to 28" before I deflexed the handle it was starting to take some serious(I thought) set. I think deflexing took some strain off the bow letting it hold a bit of the reflex I heated in. It was 175fps before so it looks like just changing it to RD got me 6fps.

Fantastic experiment and nice results as well. I'm a very firm believer in the advantages of deflex.

[DC]

I think the total reflex has to stay the same so I'm thinking it has to be reflex deflex rather than just deflex. That said, I've never made a straight limbed deflex bow. Have you?

[Badger]

That was a very valuable test you did there it clearly demonstrated the benefits to D Flex. D Flex put the limb in the right position to start bending right out of the handle right from the start it makes for a little higher energy storage and takes the strain off of some of the Lim