Custom Cowling - RC Groups
Thread Tools
Feb 27, 2012, 05:25 PM
Redacted per NSA "suggestion"
dedStik's Avatar

Custom Cowling

I've a PT 40, it's missing the nose cheeks from a crash of long ago. I would like to make a cowling for it, I have thought about buying a ready made that would work, but I think a custom made one will look better on the plane, not to mention I could probably make use of the skill set involved down the road on other projects.

My question is would I be better off going a fiberglass route, making the mold then casting from it, or would vacuum molding be a better solution. I'm looking for ease of casting and overall look after completion. Or some other method I've not thought of. Those are pretty much the only ones I've considered and done some research on.

The cowl will be a 1 off, maybe 2 if a crash occurs, but the process I'd like to use with other models down the road.
Sign up now
to remove ads between posts
Feb 27, 2012, 08:52 PM
KE your cub.
Curare's Avatar
IMO a glass cowl makes more sense.

The only time I've liked vaccum formed cowls was when they were a single peice. Multiple peice cowls always broke, and never looked very good, or if they did, were nearly double the weight of a glass cowling.

Making a glass cowling is a lot more labor intensive, however it does pay dividends, in the fact that you'll have a lighter stronger cowling, and if you mangle it in a crash, you can just pull a new one from your existing mould.

A bit of time spent perusing the 'composites fabrication' forum here on RCU will give you a good idea of what you're up for.

Another way to go may be to build a balsa cowl, that's integral to the fuselage. It's a lot easier and with some effort can be very nice to look at!
Feb 28, 2012, 09:21 AM
Redacted per NSA "suggestion"
dedStik's Avatar
My efforts are not only for looks. I'd like to take out two birds with one stone so to speak, I'm looking at the heaviest option. I'm anticipating my project to be tail heavy and I figure a cowl can counter some of this weight. Fiberglass is an option, I've worked with it in the past, on wings and also repairing surfboard dings.

I had intended if doing vacuum mold to make it one piece, either solution though I am concerned with fuel hatch access, it has to allow me access to the fuel hatch for battery swap out. I think keeping that in mind I'll lean more heavily to the glass solution. Thank you for the help.
Feb 28, 2012, 10:38 AM
Dieselized User
gkamysz's Avatar
The easiest way to make one would be to shape one from foam, glass over the foam, finish and paint, then melt or scrape out the foam. This will be a little more sanding to get a nice finish, but much less work than making a mold of a one off cowl.

Feb 28, 2012, 11:48 AM
Registered User
LesUyeda's Avatar
What gkamysz said.

Blue foam handles very nicely; carves, sands, shapes. Rather than scraping out the foam, find a solvent for whatever you use for the form and dislove it out.

Feb 28, 2012, 12:56 PM
Dieselized User
gkamysz's Avatar
Solvent is fine just make sure you don't dissolve your primer/filler!


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Help! Elite alpha 450 cowling and motor upgrade osamma Electric Plane Talk 0 Mar 11, 2011 11:58 AM
Discussion custom cowling MoD_Eagle Fuel Plane Talk 3 Apr 28, 2006 10:13 AM
TigerMoth with custom cowling by Anheuser-Busch Chuck Parkflyers 4 Feb 09, 2002 01:17 AM