Help with fiberglassing/ reinforcing HORNS!

[JayOneSeven]

As I don't really have time to look through the 280+ pages of the "Help with fiberglassing" thread in search of this one question, has anyone ever some up with a sure working way to fiberglass and reinforce the horns of a helmet?
My only thought so far was using pipe cleaners, bent in such a way that they can reach down into the tips, to push the fiberglass strips into the bottom. Perhaps then somehow turn one of the pipe cleaners into a paint brush and apply the liquid component. I'm still a little hazy as I've never fiberglassed anything, but this stands out to be a problem already! :/

 

[RobotChicken]

Just throwing this out there, but if the horns are short it shouldn't really be any problem. But I'm guessing the horns are very long and thus the difficulty - so maybe it's an option to not pep the entire length of the horn before hardening? Since they're probably conical, they should hold their shape so if you pepped, say, the first 6" of the tip, resined it, added glass (but not all the way to the opening, so you have room to glue the tabs for the next segment), then added on the next 6" of pep and repeat. Would that work?

 

[Jason 078]

I was going to suggest slushing it, but RobotChicken's idea is better.

 

[Katsu]

While you understandably don't want to leaf through the sticky as that is a lot of pages. This still could have been posted there.

Building it in pieces is an idea, but you will definitely have trouble fiberglassing the tip of the horns without getting air bubbles, and the process may be a bit more time consuming to do.

The way Jason mentioned is a pretty common method. You pour rondo inside, slush it around to coat it, and then use an expanding foam to fill the rest of the way.

 

[JayOneSeven]

I see, those sound like great ideas. Sorry I didn't post this there. And yes they are long horns :]
They're ram-type horns, about 1 foot in length with a 90 degree bend in them like a usual curve of a horn. I'm thinking the 'slushing' method would work great as I've already pepped them!

 

[Katsu]

Yeah, fiberglass struggles on tight areas (the tips of the horns) and sharp turns or complex surfaces, so it can be tricky to do (but not impossible).

If you slush, I suggest a slush of rondo, and then the expanding foam. The rondo gives a stiff exterior, and the expanding foam solidifies the inside (because rondo can crack if it's not filled) while not being super heavy. They probably won't be able to take any headbutting unless you replace the rondo with an expensive two-part plastic like smooth-on.

 

[JayOneSeven]

If you slush, I suggest a slush of rondo, and then the expanding foam. The rondo gives a stiff exterior, and the expanding foam solidifies the inside (because rondo can crack if it's not filled) while not being super heavy. They probably won't be able to take any headbutting unless you replace the rondo with an expensive two-part plastic like smooth-on.

Awesome I'm gonna give it try. My other thought (once Rondo'd) was to drill a tiny hole in the very end of the horn, just thick enough to get the expansion foam nozzle through, so i can spray it into the end. Then I could simply just patch over the tiny hole and not have to worry about a hollow gap in the tip. Do you see any issues with doing that?

 

[Katsu]

You could do that trick if you were putting fiberglass in. With rondo it will get the tip of the horns easily.

 

[JayOneSeven]

You could do that trick if you were putting fiberglass in. With rondo it will get the tip of the horns easily.

Awesome thanks I'll update when I get to that stage!

 

[gin tekidan]

Yeah, fiberglass struggles on tight areas (the tips of the horns) and sharp turns or complex surfaces, so it can be tricky to do (but not impossible).

If you slush, I suggest a slush of rondo, and then the expanding foam. The rondo gives a stiff exterior, and the expanding foam solidifies the inside (because rondo can crack if it's not filled) while not being super heavy. They probably won't be able to take any headbutting unless you replace the rondo with an expensive two-part plastic like smooth-on.

My mask has horns as well, and they are kinda lightning bolt shaped so I had planned on slushing them, but as for the foam does it work so long as its polyurethane? I think i got stuff for blown tires instead of the right stuff, but hypothetically if you hadnt heard that would it still work?

 

[Katsu]

The type of expanding foam you use totally depends on your options, needs, and costs.

Things to be aware of:

Some foams won't expand/cure without oxygen, so when using it on really deep, sealed recesses it may not operate properly. The one I used like this I was able to activate it by pouring a little water in... for some reason that worked on that brand but I dunno which one it was.

Some foams are soft and squishy (sponge-like), some are firm but brittle (styrofoam style), and some are dense, heavy and strong (brick!). There are times when each is important. I like the last one but it is a butt to grind through with a dremel.

The bottom line is... these foams and slushes are inside a "solid" object, meaning in theory you won't ever be TOUCHING the inside of horns or guns. As such, the material doesn't matter as much and I'd just worry more about what you have access to, and whether it will STRUCTURALLY work right. And also.. making sure it won't dissolve rondo, which seems to be a bit difficult to do.