Noah-Moore

I was wondering if there is a way to make a fiberglasss fuse without having to make plug and all that stuff. Could i just carve something out of foam, then cover it in fiberglass. When it is dry cut it into two halves and dig out the foam. Then glue it back together.

Thanks

Mike James

Yes, you can. It's called the "lost foam" method. Personally, I would only use it for something small, that I was sure I wouldn't need to reproduce.

Obvious "catches" are that since it's a "one-time-only" process, if you screw something up while making it, or damage it later, it's tough to replace. Also, it's unlikely that you'll get ALL the foam out, resulting in somewhat heavier parts.

If you're making something that doesn't have much detail in it, the lost foam method is fine. But if you're going to make your plug look really great, you may as well make a traditional plug, so you can reproduce them as needed.

The whole process of plug and mold making is documented on my non-commercial web site at http://www.nextcraft.com. I also show a "Flying Wing" project that used the lost foam method for the fuselage. (a one-time-only plane)

Good luck with whatever you're making.

JayParke

If you're gonna do a one time only fuse then why not just pour gasoline in the fuse and let the gas eat all the foam. Then dump it out? It may save the hassle of cutting it open digging the foam out then gluing it back up. But of course I think it would smell pretty bad but I bet with a good cleaning all the smell will come off. Or even perhaps use something different than gas?

I haven't tried this method, but I hear all the time of it being used.

Josh

Edwin

My Feedback: (2)

Just rinse it out with soapy water when you're done with the gasoline, it gets rid of the smell. Thats how I make my cowls. I would suggest you put a thinned layer of water and white elmers glue over the foam first. Fill in any divits with spackling. Then a last coat of thinned water and elmers glue. This gives you a smooth interior. Otherwise you end up with a bunch of little spikes from the epoxy/resin bleeding into the foam. After the piece dries, I usually use a crown and round wire brush for a dremil to finish the cleaning out. Goes fast takes 10 or 15 minutes normally.
Edwin

Noah-Moore

Edwin,

I like your method of using the glue and water. I never thought of this. I'm going to give this method a try.

Edwin

My Feedback: (2)

Didnt think of this till later, but on a part with no room to work with on the inside you might be able to go to a car wash and use high pressure water to blow the sludge out. I know my cowls would handle it. Maybe a small fuse. Gotta try that next time. I was thinking it would be cool to make a small glass DF fuse.
Edwin

ProfLooney

I use acetone to eat the foam but it all depends on what you use to glass with as it evaporates totally gone, leaves no residue, and evaporates away totally no nasty scrubbing or all that to get residue out.

Joe

Edwin

My Feedback: (2)

You see there, you can always learn something new. Got to try that next time, proflooney.
Edwin

ProfLooney

I used to be plant manager at a fiberglass boat factory had a lot of experiencew playing around with the RC hobby. I mean why not hehe all the fiberglas I can play with for free and the nice part is the acess to the chopper guns so i dont have to mess with hand layups. Another one I am not sure on but should work like acetone does it is mainly just weaker is called MEK Methyl Ethyl Keotone I think you can get thet at wally world , lowes, meynards, Home Depot too

Joe

Mike James

Since we can't tell what a participant's age or experience is from merely reading these posts, I just want to add one thing.

If you use some of the things mentioned above, expecially Acetone, gasoline, or MEK, be VERY careful. Some of these things are highly flammable, some can cause permanent blindness if you get them in your eyes, and all of them will create a big, gooey mess, if used to melt styrofoam.

At least take a minute to read the labels and follow the recommended safety procedures. These chemicals are useable, but please just be careful.

ProfLooney

good suggestions too often we do forget abt various ages. I can say acetone is very flammible as I have seen a ash from a burn barrel ignight a paper shop rag which was almost dry of acetone catch fire. Acetone is fairly safe health wise. if you get a splash in your eyes you dont have to worry it will sting for a few minutes but nicely cleans out your eyes (I have had more than a splash several times into my eyes and the Dr has told me nothing to worry abt that it wont hurt anything) Also acetone is very good for cuts as it works as an anticeptic. If you look at a lot of topical medicines one of the main ingredients is acetone one example is absorbine junior for foot itches etc it is 65% acetone. If you ever cut yourself in your workshop say slice your finger with an exacto soak it in acetone. again it will sting but it will help the cut to heal 5 times as fast and will disenfect it. MEK has similar qualities but not near as good as acetone.

Joe