Best formula for fillets

Hi,

What is the best formula for strong but light fillets? For MPR & HPR .

I use NHP 30 min epoxy which is a 50:50 mix. I want to add microspheres or milled fibre. What is the best ratio of spheres / fibre to mixed epoxy?

Any input appreciated.

Kev T

Reply to
Kev Timmins
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I still think the best way are 2 pieces of fiberglass cut in 1 larger and one smaller rectangular pieces. Tack the fins with JB weld and work in the larger piece first and then the smaller piece. No need to go fin tip to fin tip. This is much stronger without much added weight at all than any epoxy plus additive formula.

Koen

Reply to
Koen O. Loeven

For wood and paper rockets, yellow glue.

THe 50:50 mix epoxies tend to have fillers in them already, and don't mix or work that well with additional fillers. Your best bet is to get one of the thin epoxies like West, System3, Raka, etc and then add the filler(s) of your choice in the amount of your choice. THey tend to be much cheaper than the mass market epoxies too.

For fillets, I like to be just short of a thixotropic mix, so it will still level itself out smooth, but minimize running. I'll add microballoons and not quite enough of a thixotropic filler. I go for a honey-like consistency, instead of peanut butter.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

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