[secant0give]

Thanks Frank,

The wing on this plane so thin that even micro servos stick out through the bottom surface. I haven’t flown it with the new fairings on yet, but it should make for a reasonable reduction in drag.
The previous fairings were laid up in the mould, covered with cling film, then a sponge was put on top and a weight on top of the sponge to hold the layup against the mould. It would have been easier if I used a few layers of much lighter cloth, but I have heaps of 6oz that I wanted to use up. The sponge conformes to the shape of the inside of the fairing and holds the cloth and resin nicely against the internal corners of the mould. Epoxy doesn't stick to cling film so that separated the sponge from the inside of the fairing and was easily removed after it cured. The section that goes over the linkage is separate piece, made from the RareBear linkage fairing.



While I'm waiting for the paint to really harden up on the plug for fuse, I've dragged out my old vaccum pump, changed the oil in it and tested it out moulding some more servo fairings. This time I vac bagged them into the mould. The bag is just a clip lock bag and since it's made of similar material to cling wrap it doesn't adhere to the lay-up either. The strip across the two moulds inside the bag is a wick to let the air out. It's made from a piece of cotton cloth folded up in a strip of Peel ply. Peel ply forms a porous layer that will release from the layup. It will just peel off the inside of the fairing before I pull it out of the mould. If I didn’t put a wick in there I don’t think it would have sucked right down into the shape of the mould.

Here’s a pic of the Lay-up, one layer of white paper on the outside and then one layer of 6oz glass, cut from 6oz tape. The paper is cut from the corners so it will take the shape of the mould with out wrinkeling. The resin I used was Hobby king 30min epoxy so it's pretty thick and it's not so easy to wet out the cloth. But it has the advantage that it is easy to mix in small ammounts and is cheep. Although it's a 30 min epoxy it's not stiff enough to take out of the mould for about 12 hours and is still a bit plyable even then, but cures nice and very crisp after a couple of days.

   

Here it is in the bag

   

Here’s my ancient Vacuum pump.