Stuck on Epoxy
 

I am putting toghether a glider that has foam,wood and plastic pieces. What is a real good epoxy to use on this. I am needing to mate the wings together which are made of styrofoam wrapped with plastic, and also at the joint there is a 3 piece plywood spar that slides into the foam. I have some epoxy that I used on a balsa wood kit and it doesn't want to stick that well. Do any of you guys have any ideas? Thanks much.

RE: Stuck on Epoxy
 

From what I was told epoxy will melt the foam and will not hurt the plastic or wood of course.

Check this [link=http://www.misterart.com/store/view/001/group_id/1832/Beacon-Craft-Foam-Glue.htm]Foam Glue[/link] out and see if it will give you the bond required for the stress the wing will under go while flying.

P.S. I never used the stuff myself. ;)

Good Luck

RE: Stuck on Epoxy
 

Epoxy will not hurt or melt the foam, but it may not stick to the plastic
very well. You may want to lightly sand the plastic to aid bonding.

Sometimes, like with the old Lanier Arf's....the best thing to bond to the plastic
was plain ol' RTV silicon rubber seal. ;)

I wonder how that new Gorilla Glue would work ?

FBD.

RE: Stuck on Epoxy
 

Like Flyboy Dave wrote: Gorilla glue would work.

I used it on skinned foam,and plain foam,Use very little because it expands ALOT.

RE: Stuck on Epoxy
 

Yes, use polyurethane glue. But, you may want to experiment with it first. The amount of expansion is dependant on your relative humidity and ambient air temperature. The hotter and wetter it is, the more expansion you get. Good luck.

RE: Stuck on Epoxy
 

Hey Deadeye

Would you know what makes Gorilla glue faster ?

I ask becauce you seam to know alot about this glue.

RE: Stuck on Epoxy
 

The only epoxy that may get hot enough to damage the foam panels is 5 minute epoxy. It gets pretty hot due to the chemical reaction, however you will need more working time to get everything set in place. Use 30-minute epoxy. I have used it on foam with success. Your LHS will be able to fix you up.

RE: Stuck on Epoxy
 

I have lots of experience with Polyurethane. In Montana, our air is dry. Unless it's raining we are usually less than 20% humidity. Therefore, I have to spritz my glue with water during it's cure stage. If it is a critical joint, I tend to use more glue and less water. The more the glue expands, the weaker the joint. If the glue is expanding too much for your tastes, you can hit it with a heat gun to evaporate the water faster (you can actually watch the glue cure with enough heat). If my temperature and humidity is right, I can just about set my watch to the cure time, usually 3-4 hours. If I lived in Jamaica or Florida, that cure time would be cut in half.

You just have to experiment. I took an 8 oz dixie cup once, dribbled about 1/4 inch of poly glue in it, and covered that with about 1/2 inch of warm water. The air temp was 80 or so, and within 30 minutes that glue had expanded over the top of the cup. In 2 hours it was set up hard as a rock.

RE: Stuck on Epoxy
 

Thanx Deadeye

You just helped alot of us.

Thankyou Again

Matt

RE: Stuck on Epoxy
 

K-DOG , The moderator is right and wrong at the same time. EPOXY is 1/4 CA glue, so there are some epoxies you can and can not use. and if you do a search on epoxy they will give you and explanation of what each type of epoxy is used for foam.

Good luck.

RE: Stuck on Epoxy
 

"Epoxy is 1/4 CA glue". Where did that come from RC-Fiend? There is zero truth in that statement. All epoxies designed for R/C hobby use can be used on foam.

RE: Stuck on Epoxy
 

WHAT!!!!!! Where's it at -- in the resin or the hardner? If you can give me a brand that has CA in it, I'll investigate, because I've never heard of this before.

RE: Stuck on Epoxy
 

I seriously doubt that any epoxy contains CA glue, they just aren't compatable.

Any CA however WILL melt foam unless the container says "foam safe".
Dennis-