carbon/ kevlar?

[steveo]

the tunnel on my cat is a little more flimsy than i like and would now like to stiffen it up , i think with the flex i was having during the few runs i have had caused my motor mount to come unglued in one corner its still secure but for how long, i was thinking of using a 1/8 thick ply and gluing it down but maybe there are more options

[domp444]

Kintec Racing has Carbon/Kevlar cloth which you could put down in the tunnel, you can find it here. I'm not sure how to apply it, but it should be pretty similar to laying down fiberglass. Plus, it's really strong.

[Eric Bourlet]

I would stay away from Kevlar unless you can vacuum bag. It is hard to get it to wet out right unless it's bagged. It's also a real pain in the tail to work with. I bagged my Anderson MuttII Sport 40 deck with a carbon Kevlar weave and will never work with that stuff again. It fuzzes and is hard to cut... I would recommend a 2x2 carbon twill

[Chris Harris]

I would stay away from Kevlar unless you can vacuum bag. It is hard to get it to wet out right unless it's bagged. It's also a real pain in the tail to work with. I bagged my Anderson MuttII Sport 40 deck with a carbon Kevlar weave and will never work with that stuff again. It fuzzes and is hard to cut... I would recommend a 2x2 carbon twill

YUP! What he said

Chris

[domp444]

I guess I was wrong. Sorry, I don't have much experience with Kevlar.

[Gerwin Brommer]

Carbon or kevlar on a flat tunnel doesn't add more strenght to it than just plain glass.
The motormount itself could add enough strenght to the tunnel, if glued in the right way.
Did you just glue it, or did you also secure it with a (or more) layer(s) of cloth ?

Another option : make the motormount longer or/and wider !
On a real bad-ass boat I once made for a customer, I made the motormount as wide as the tunnel.

[dasboata]

I have some 2x2 twill that I would sell at a fair price I over bought for a project I am working on LMK thanks Chris

[steveo]

Carbon or kevlar on a flat tunnel doesn't add more strenght to it than just plain glass.
The motormount itself could add enough strenght to the tunnel, if glued in the right way.
Did you just glue it, or did you also secure it with a (or more) layer(s) of cloth ?

Another option : make the motormount longer or/and wider !
On a real bad-ass boat I once made for a customer, I made the motormount as wide as the tunnel.

what i should have done and i know better is to lay down a down a sheet of ply, now thinking it over is what i am going to do. i am also going to through bolt the motor mount with small button head screws and washers through the hull

[befu]

I have some 2x2 twill that I would sell at a fair price I over bought for a project I am working on LMK thanks Chris

please pm me with details on some of the 2x2 if he is not interested in it. I want to build a light weight mono for someone and that would be some nice stuff to work with, but it is SOOOO much more expensive the the stuff in the 5oz range.

Kevlar is awesome stuff, most of my build include it as I really like working with it. The other good thing is, it will work with polyester resin, about the only high strength composite that will work with polyester resin.

Good stuff, but it can be "touchy" to work with especially if you do not have any previous experience with it. I usually like it more than carbon fiber!

Brian

[larryrose11]

I had great result with 2oz fiberglass / epoxy. I cut out 2 layers to fit. Mixed the epoxy, and brushed on as thin of a coat as I can, making sure I got coverage. Starting from the middle, roll the glass mat on, and push out the bubbles with the glue brush. repeat. Make sure you push all the extra epoxy out, and soak it up with a paper towel.

[Fluid]

The thing to remember is that different fibers impart different things to a hull. Carbon is best at adding stiffness, but it is brittle. Kevlar adds resistance to puncture but very little stiffness. That is why carbon/Kevlar cloths are popular, combining both features. I have seen two carbon/Kevlar boats badly crashed, and they looked like bags of broken parts. The brittle carbon and resin shattered and the puncture-proof Kevlar kept the mess inside. Ugly.



.

[Doug Smock]

I'm not a big FE cat guy so please pardon my ignorance.
Wouldn't some well placed stringers not do a better job at stiffining up the tunnel and weigh less than the cloth and or plywood and resin?

Doug

[steveo]

i have thought of stringers the length of the hull but there would still be alittle twist in the hull from motor torque i assume, there is not as much flex side to side than front to back a flat sheet of ply will stiffen all, the weight of the wood will be minimal, i will be going up to 5s2p with a 1520 in the future so the stiffer the better, this will not be my final solution i am sure

[forescott]

I epoxied a piece of thin hobby grade plywood to my TC-31. It adds all the strength you need!!

[DISAR]

Even 3/16" carbon tubes glued to the tunnel add stiffness. On one boat I used carbon tubes and on another thick fiberglass 18oz but the surface must be flat for both cases.
Another option is to use rigid wide servo-mounts or motor or esc mounts glued on the tunnel which really act as stringers and as mounts.