Resin rich patches, how to improve finish

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#1

Hi,

I hand laid up a canopy for my friend’s rc plane.

The weave pattern looks great but there are certain patches of resin.
The non resin rich areas are just fibers (you can feel weave on touch).

](http://postimage.org/)[/IMG]

Initially I had planned to just spray lacquer to give a nice glossy carbon fiber finish. Shall I do the same now? Or should I sand the excess resin regions first (proving to be very difficult).

Or should I first apply a thin coat of resin by hand and brush, then sand it, then add lacquer as certain youtube videos suggest?

Suggestions will be appreciated.

Thanks in advance

#2

You will want to apply a fair thick layer of resin to the entire part to give you something to sand into. This isn’t so much resin rich areas as it is a rather dry surface. You don’t want to bite into the fibres at all when you sand it, so you will need to apply resin to the entire surface.

This resin won’t cure flat, so prepare yourself for a fair amount of sanding. I would do one thick layer now, sand it as flat as you can with 60 grit paper (being careful not to break through to the fibres!), and then do another coat of resin. Dry sand this layer almost flat with 180 grit, then progress to wet sanding at 240 then 320 then 400 grit wet and dry paper. You want to be getting the surface completely flat with the 400 grit paper so that you don’t have to rub through too much of your resin. Once you’ve flatted the surface with the 400, rub it down once more with 600 grit paper and then spray your clear coat.

#3

you need to epoxy the mold before you lay the fabric …