This weekend I mainly worked on surface finishes on the lower shell. While not much woodwork went
on, the surface finish that I’m describing here with quite a few pics takes time and patience. I won’t begin
on the upper shell and Screen drive system until I’ve more or less got the lower shell ready to receive paint.
My next step will be the rear panel of the lower shell. Still made from plywood, it will also have two access
plates on it made from thin steel and fitted with several large fans to keep plenty of air flowing over the power
supplies, amplifier and motherboard.
So, onto the surface finish technique I’m using.
First a bit of jigsaw and drill work with that 7mm plywood to create the top panel of the lower shell.....
Check to see the first cut-out fits...
Make the remaining cuts, then glue and screw it down (using some timber beading underneath). Then round off the edges with the sander.
Next I mix up a pre-estimated amount of Plasti-Bond for filling screw holes, gaps and coating surfaces.
Use deposable gloves for this and apply with a plastic applicator similar to the sort used for mending small holes in plasterboard.
It sets fairly quickly depending on how much hardener you use. It has the consistency of butter when mixed.
When it starts to go lumpy don’t try and push it around anymore or you will have a horrible mess to try and remove.
You can always mix a fresh batch and add more. Never put an applicator or mixing stick into the tin – it can ruin it.
Apply using broad strokes; try to aim for an even smooth surface. And sure, it looks pretty awful when just applied!
Leave it to dry for about 30 minutes minimum, up to an hour on a cold day. Then sand back with coarse grade sandpaper using an electrical sander.
When all bumps are gone switch to fine grade sandpaper. Hand finish with very fine (600 or higher grade), wipe down
all surfaces with a damp rag to remove all dust.
Take automotive spray putty, shake well and lightly coat with several coats, allowing a few minutes between coats.
In a previous post I said a 400g can costs about $6.00 in fact its more like $12.00.
Allow to dry for about an hour, or at least 30 minutes then hand sand lightly with fine to very fine sandpaper.
The finished surface should be like an automotive panel prior to primer coat, no wood grain, no bumps, nuthin, just smooth!
Normally a final finish needs some touch up work with Plasti-Bond into small pits, exposed grain etc which shows up
after a coat of spray putty. Repeat the process until satisfied.