Hi Richard.
I've just completed my stabilizers - now ready for top coat - and it took
much longer time to accomplish than I ever anticipated. Mainly due to
pin-holes which popped up in a mysterious way during sanding. I found that
the thicker the mix - the more pin-holes you get. (Trapped air-bubbels which
won't let go in a thick mix). I'm also using Expancel, and I mix with SP 106
epoxy.
While everybody advocates a thick blend due to the weight issue, I find
nevertheless that a more moderate - or leaner - mix is far better to work
with and leaves no pin-holes at all! I don't think the very small weight
increase incured is of such an importance - than having to spend several
extra weeks of filling and sanding - filling and sanding........... Any
numbers on this, anyone??
Instead of the "fishing line technique" I used series of master strips
spaced equally apart chordwise (by the width of my 14" spatula) and sanded
them spanwise - on a 45 degree pace either way by a 50" long sanding spline,
to almost hitting the glass. Filling between the strips was easy and
subsequent sanding down to the substrate was easily controlled. My spline
has 60 grit paper to realy get the high peeks down, but don't get carried
away though! In due time change to finer grit, and when hitting the glass -
STOPP! The whole procedure could have been done in one go only, but of
coarse the pin-holes are an all different story.....
This procedure was most kindly offered by Nigel Graham on this mail server
som time ago.
Regards,
Hans.#334
----- 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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