Hi Richard,
I have been fooling around with this a bit of late. I am using Expandcell
mixed with Carbosil in a 4:1 ratio. For Epoxy I am using the West System
resins with the pumps that screw into the top of the cans. I use one pump
of resin and a cooking measure stolen from the kitchen which is a "1/3rd"
cup scoop. I put in on scoop and mix it then add another 1/3 scoop. This
give a pretty dry mix that I squeegee out on a nylon board.
To apply it I put on a really thin layer of epoxy onto the surface and then
put on a good coating of Expancell mixture. To get the thickness even I put
on two nylon lines on the surface stretched out with a weight at each end.
(The nylon line is 40 thou thick "whipper snipper" line.) I then spread
this out with a 150 mm wide plastering knife. I have discovered that it is
far easier to put on too much and sand it back rather than put on second and
third coats.
The above techniques were shown to me my good friend Graham Singleton so I
claim no credit, but I can say that it works pretty well. I think I have
described some of this along with some sanding tips in December, see
http://pma.obtero.net/
Cheers, Paul
----- Original Message -----
From: "Richard Iddon" <riddon@btinternet.com>
Subject: surface filling
> Hello the Oracle,
>
> I've just attempted to surface fill my first flying surface with factory
> supplied Expancell and have a couple of questions.
>
> 1). How do I judge the consistency of the mix, is it too wet if there is
> 'moisture' visible on the surface?
>
> 2). How thick should I layer the filler on? If my layup is fairly smooth
&
> flat, do I need just enough to fill the weave or thick enough so I can't
see
> through the fill and then sand back?
>
> 3). Any tips for getting a smooth, even finish?
>
> Any other tips would be appreciated.
>
> Richard Iddon (still waiting for my wings)533
>
>
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