Delamination (sp) =(

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#1

Well, not sure why its happening

Using a Clear Gel Coat
Epoxy Resin
The resin CPS is VERY low, almost like water. works great.

Not sure why this is happening on all the parts that i try diff. epoxies. It might be due to the fact im using super 77 and its not getting eaten away with the epoxy so its creating a thin film and the epoxy doesnt adhere to it well.

its 1 kevlar, 2 fiberglass 9oz. came out GREAT!!! some mistakes here and there, but this is all trial. i think its the mold really. i have been doing bad things with it.

can VER help? i can bend the part slightly and all of a sudden the layers are splitting. you can see this in the pic above, the yellower the color, thats where the seperation started!.

heres a nice pic


notice the little spot where its missing resin. =\

#2

1 more thing, how the HELL do you cut kevlar. i have a diamond wheel on a dremel and damn, its just fraying the edges after awhile. how do i make sure i can cut, then sand lightly??

#3

How long was the part allowed to cured and such before twisting it? Sometimes it can days to acheive full cure.

Try a bandsaw and invert the blade (teeth pointing upwards) to cut cured Kevlar. Or in the classsroom when also had Fein tools and they worked great but mostly in a straight line.

#4

If you are using a very thin resin, your problems are almost certainly being caused by there simply not being any resin in the problem areas.

Maybe if your parts are purely cosmetic you would be better to look to try using poly RTM resin (assuming you are using RTM process, rather than hand laminating).

#5

well i did not mention that i applied a bit of heat using a heat gun on top of the part while the resin ran through it. it helped. i really dont think the delam. is caused by the resin being to thin, i think its the super 77. =(

#6

unless you used a heaping coat of the 77 its probly not that.
Most likely the resin isn’t getting to those areas. One thing I’ve noticed in a few of my infusions is if you let the resin get into the vac line before the laminate kicks, it cures and you can lose vacuum (ie. the compression is lost) this poses a problem if you have even the slightest leak in the bag. When the compression is lost, well the layers aren’t being held together

#7

A co-worker of mine (who no longer works with me) used to spray 77 from like 6" away. Needless to say the cloth in those areas would never saturate with epoxy. We ended up throwing away a lot of cloth because of it.

Your first photo looks similar to what happend with my co-worker.

Ive been spraying (lightly misting) cloth from as far away as 3 feet and it still tacks the cloth up nice.

#8

I really do think its the super 77. and i hear that ver will work with it well.

#9

Ive been using 600cps epoxy with it for the past few weeks. It works just fine. VER works well for sure.

The key is to use as little 77 as possible.

#10

well how do i make sure the fiber’s stay put in certain spots. i have really tight corners. =(

#11

have you tried post curing the part?