more on the FRLB Disaster!

[Forwardhandle]

Well that blows    for sure I had the one last year do the same ,do to bad form pressure, I use Kennys recepe of 2 in fade , .140 at 2" , .065 at 1" & paper on the end I have been exstending the fades back farther lately sense Im pulling 31" there is a lot of presure on the fades in this design I always hand lap the fades with sanding blocks to make sure every thing is dead flat and smooth but I seriously dont think those fades bend beyound the 2" mark so every thing needs to be perfect in my mind , after blowing one I spend a lot of time on the riser area & riser fit & havent had any more issues !

[Roy from Pa]

Damn Bobby that sucks.

Glad you didn't get injured when it left go.

You going to put another one together?

[bigbob2]

thanks guys. Yep going to try again Roy. Got lucky when it went, just a small rap on the snout from the bow arm but nothing really.I did have some small doubts about the fade area but it fit so well on the form I decided to go with it as is.It is the correct length etc, just that the ramp heading back from the tip of fades is just a little too deep at a given point,. not a big thing in the scheme of things but with this design, that "little" thing was surely enough.Any one building one of these would be advised to spend time making sure the fades are spot on, with a shallow curve away from tip, I believe the standard .1/16'  @1'' and .1/8' @ 2'' is the right dimensions. Mine were perfectly flat, true etc but the radius just a little insufficient, loading up an area of high stress. Unreal the way the belly glass just sheared strait across about an 1'' in front of fade.That to me denotes the fades were too rigid and acting as a fulcrum point causing the shear and resultant tearing of lams and glass.Bummer, too good a design to just leave it at that so mark 2 will happen. just have to wait for some more epoxy.

[Crooked Stic]

I never seen glass break clean across like that. I agree that the fades could be thinner. I also wonder about the thick belly over lay maybe too close to the fade and not allowing that area to flex enough. A way to cure that would be a G 10 ibeam. Even a PL just a couple of in. past the fade. The superlam.

[bigbob2]

Definitely going to use super lams on next one. I have never seen glass do that either. Bit bizarre actually. I don’t  have access to suitable thickness of G10 at the moment , might just  have to go with super lam.

[Tim Finley]

Just looking at the pictures (hard to tell) but the fade outs look ok to me, it may be your 31" draw lots of bows cant take that long draw length . I used to have a 31" draw length when I was young and I broke lots of bows . I finally started shooting a 66" bow and they stood up .

[Mark R]

Could it be the last couple of inches in the fades that reflex opposite from the limb when flexed at full draw might be to stressed.

[Forwardhandle]

I think this design can hold up to long draws fine I have been pulling the glass 60" to 31" for 800 or more arrows & got about 450 arrows threw the carbon 60" with no issues, I have been exstending my fades out a little bit farther on current bows like in the pic but all where made with the SL in the stack , The PL part of the super lam exstends the fade out aprox 2 1/2 - 3 " depending on where you start the front profile having made the 60 & 64" version my guess is the winner for 31"
Draws is going to be the 62 " but just speculation the 64" is a amazing bow the down side is a little higher brace height , Bob sorry you had to be the pioner on the no SL but at least you answered that question ! I see another in your near future 

[bigbob2]

Thanks guys for your input. Re the long draw, my own draw with stick bow is only 29” , I drew to 30- 31 just for illustrative purposes. I will extend  the fades a little, add a power lam and see how that goes. This is why it was made from shop scraps anyway.

[kennym]

Man that sucks Bob!! I don't have any theories that haven't been offered up, wish I did!

[Crooked Stic]

I really dont think your draw is too long. I would be more worried about maybe that glass had a defect. If you look at this Shrew riser fades and they are bragging about being able to go past 30 in. on them.

[bigbob2]

Yeah see what you mean. Fades are actually thicker than mine! Going to start on mark 2 soon.

[Forwardhandle]

Mike do you know what taper rate they use on the Shrew ? Bob the more of these you make the more questions you get then answers  but Mike poped some veneers, I poped one & you did so we know the fades/ riser are critical the Devils in the details...lol  Im thinking with the SL the riser fade angle might be a bit less critical with the SL fade exstention
but any relief in that area probably helps ! All speculation on my part but glad we can share notes 

[bigbob2]

The weirdest thing is the way the glass first sheared, before it then delaminates. I have seen quite a few destructed  bows over the years but this almost looks like it was cut clear across the glass. Definitely strange. I have started on mark 2 so let the fun begin.

[Crooked Stic]

Dont have a clue what the taper would be on the Shrew.

[kennym]

Wonder if the shrew has a power lam?

[Forwardhandle]

I dont know but bet it does, Bob mine blew do to poor form design I used wood pegs with the topless @70 psi and some pegs broke while it was baking Im not saying its a issue with the design just some thing that needs a critical eye !

[Crooked Stic]

Nothing wrong with the design. I got one prolly close to 800 arrows thru it. Two buddys  and two 35 lbers. out all working fine. The second one I done delamed while building it
. I blamed it on the form that had the hump on the face. That is when I changed the form.

[kennym]

All fades should be real gradual IMO, some bows can get away with less gradual, others not so much. Power lams are great to help this area...

[Forwardhandle]

I have often wondered how far the fades bend back in to the riser on this bow but sandwiched between glass or glass carbon I really dought it moves back any farther then 2" it might be a feel good move on my part smoothing them back but can't hurt when I get my risers all thinned I put them on a clean flat surface and flex them to see if there bending the same but even with the light pressure doing that they stiffen up quick with in a in.  or so !