Erich Trombley wrote:
>You mention that one shouldn't use anything more coarse than 80 or 120
>grit but then later on you state to "Start with 36grid paper to sand down
>thick layers."
Use 80 or 120grit to sand down the ridges, just the ridges.
Use 36grit when you are sanding a whole surface and there is a lot
of filler to remove from that surface. Use it on your long spline
(our splines are 1 meter or so in length). Be sure to switch back to
80 or 120grit in time.
>Also please expand on the following, "If you do need extra filler then
>bring up a whole new (thin) layer, do not add filler locally except to
>the very last stage."
If you "hit" the glass somewhere while sanding and there are still some
low spots not hit by your sanding spline then your layer of filler was
not thick enough. It is tempting to just fill the low spots with a second
layer and start sanding again. Don't do this. First you almost certainly
will sand into the glass you hit before and second it is very difficult to
"blend" the edges of the second layer with the first layer. So bring up a
whole new layer, thick enough to fill the low spots and also thick enough
to just cover the areas where you hit the glass.
If it is difficult for you to determine whether there are any low areas
left to fill then you can spray a very thin layer of black or gray paint
on the surface and start sanding. The paint will disappear at the high
areas and remain at the low areas. You can also use a surfacer with some
black or gray pigment. Ask your local SP Systems supplier.
Good luck,
Henk & Bart #264
|