Glass ??

[Crooked Stic]

I bought some strips that the guy said was core tuff. All the coretuff I have had has been uni. This I got is .030 but is woven. So what is it called?
AlsoI think it may workasgood as stablecore??

[Mad Max]

I use this from Bingham Projects before I found Stabil-Kore and I still have some
red, clear , black

Uni-weft is a continuous unidirectional “E” fiberglass laminate with 90 degree fiberglass inlay. This combination not only gives high strength and stiffness along the longitudinal (0) axis, but also provides cross strength and stiffness (90 degrees to the longitudinal axis). It provides increased tortional stability where thin or narrow limb design is used. Available in .030″ natural (no color), 2″, 1.75″, or 1 1/2″, sanded on both sides.

Go to Bingham site and look at the Pictures

[Crooked Stic]

Thanks Max.
Do you find it to be as stiff. Adding it to the stack would you subtract .030 from your core and put the uniweft in and still have the same weight?
Do you think it is as good as stablecore?

[Mad Max]

I couldn't tell any difference.
Works just like stabil-kore, subtract from the core, same weight.

[Kirkll]

it works exactly like stable core IMO.... but... its twice the thickness and twice the mass weight added to your limb which looses performance.  if you buy stablecore by the roll its a LOT cheaper, and a better product in my opinion.

btw.... dont ever use the core tough as accent lines in a riser. the edges are not good looking as accent lines at all. i don't use any glass as accent lines in risers.

.02 cents worth....  Kirk

[Crooked Stic]

 Well I was thinking I was getting uni core tuff Gotta use it up. How much performance. You gonna lose prolly not gonna see it without a chrono.

[Buggs]

"Uni-weft is a continuous unidirectional “E” fiberglass laminate with 90 degree fiberglass inlay. This combination not only gives high strength and stiffness along the longitudinal (0) axis, but also provides cross strength and stiffness (90 degrees to the longitudinal axis)."

Thats the definition of an oxymoron. Unidirectional with 90deg fiber "inlay"

[Crooked Stic]

 Not woven then ?

[Buggs]

Not woven would be an overlay. Inlay is insertion or intrusion into a surface, at which point it is no longer unidirectional.

It would be very helpful if the brochure writers for some of these companies could use accurate terminology to describe their products. 

[Crooked Stic]

Gotcha I think 

[Longcruise]

It would be very helpful if the brochure writers for some of these companies could use accurate terminology to describe their products.

I think they just copy the manufacturer descriptions mostly.

I used core tuff in a long bow once. Seemed to make it a bit doggy.  Might be more beneficial if it's ground down to .015 but why bother when stabilcore does it well.

[Crooked Stic]

A longbow should not need core tuff or stablecore. And it is nowhere near as good as .020 twill for stabilty. Too bad you cant get it with both sides glueable.

[Buggs]

Stic, what material are you referring to that can't be glued on both sides?

[Kirkll]

A longbow should not need core tuff or stablecore. And it is nowhere near as good as .020 twill for stabilty. Too bad you cant get it with both sides glueable.

So where are you buying this "Twill" at bro?  You say it gives better torsional stability in a recurve limb than stable core, but its only sanded one side?  Might be something i'd be interested in for light weight target bows. Those always seem a bit squirrely even running a par taper getting down to 35# or less.  Kirk

[Crooked Stic]

Yes sir I am trying a new limb design and of course missed the weight light came out 32 lbs.  It has worked for me buy just removing .020 from the core and put the twill on the front or if you want really solid front and belly. The only thing is if you use 2 ply witch is .020 you have to put glass under it.
The very first set of limbs I done on a known design was
.020 2 ply twill
.030 core turf
Then bamboo core
.030 core turf
. 020 2 ply twill
Rock solid stable.
I get it from Rosewood shop 65 cents an inch so it is not something cheap. The 2 ply adds no stiffness. They have a 6 ply that you can use on the front that has undirectional added and 2 ply on the belly with no glass. Thinking the Widow carbons are built that way.
Buggs the twill has a finish on one side. Slick and shiny. I suppose you could sand it but not sure it would bee wise.

[Buggs]

If one side takes glue and the material is homogeneous, the other side will also. Laminates are laid up on polished and treated surfaces for ease of release and cosmetic appearance. I would not hesitate to abrade the surface and glue it up.

[Kirkll]

Good luck with your new design bro…. That is a bit too expensive for this kid to play with, but I’d love to see the finished product.   Kirk

[Longcruise]

Yes sir I am trying a new limb design and of course missed the weight light came out 32 lbs.  It has worked for me buy just removing .020 from the core and put the twill on the front or if you want really solid front and belly. The only thing is if you use 2 ply witch is .020 you have to put glass under it.
The very first set of limbs I done on a known design was
.020 2 ply twill
.030 core turf
Then bamboo core
.030 core turf
. 020 2 ply twill
Rock solid stable.
I get it from Rosewood shop 65 cents an inch so it is not something cheap. The 2 ply adds no stiffness. They have a 6 ply that you can use on the front that has undirectional added and 2 ply on the belly with no glass. Thinking the Widow carbons are built that way.
Buggs the twill has a finish on one side. Slick and shiny. I suppose you could sand it but not sure it would bee wise.

So, why all that core tuff?  Is it to replace the strength of the typical glass?

How about taking the core tuff down to 010 or 015 and adding more wood?

Not critiquing here.  I've never been down this path but have been thinking along these lines.

[Mark R]

I've only used the carbon made for backing a bow, 6 ply and other lay ups, it's not all the same but pretty close, availability changes a bit, at least it used to, what Stick is doing may have benefits for lighter bows he should know, not sure the benefit or the cost of using a .020 ply carbon belly over glass with a 6 ply carbon back, I would think the 6 ply carbon back would give all the stability you need with a glass belly, it's worked well for myself, years ago I heard of bowyers using .020 ply carbon belly over glass  just for looks. Design has a lot to do with how well it works or if really needed at all and carbon is much more expensive to play with but can have benefits when used right. JMHO.

[Kirkll]

I did a bunch of prototype work with carbon backing, and the biggest gains in torsional stability is using the bias weave both belly and back.

 The biggest hurdle doing that is putting that carbon on the belly and keeping it from shearing at the belly lam it’s glued too. Typically that is the weak spot because the carbon does not compress, and it buckles and delaminates.

I think the best combo I came up with was using a .020 bias weave carbon belly over .020 glass , over a rock hard maple core on the belly side. That was the most durable combo I came up with. I never had any issues running carbon on just the back side, but the torsional stability gains are not even comparable to using it belly and back.

Once again…. I wish you luck with those expensive prototypes bro. I’m pretty much done with messing with building time bombs….   Kirk