eD DIY A7s-650 Mirror Finish

[Tungsten06GT]

Hey guys,

I've been working to accomplish a mirror finish on my eD DIY A7s-650 kit, but I ran into some problems after spraying my first color coat.

Here's what I've worked up to. I assembled the box entirely with wood glue and clamps, no screws (all joints being butt joints). Then I spread bondo over all edges of the EFS, and across all joints. Sanded everything flush, up to 400 grit, perfectly smooth and flush, couldn't feel any difference between bondo and EFS.

Then, used Duplicolor's high build spray filler primer. I put on 3 "big coats" (each big coat consisted of 10 smaller ones), while sanding with 400 grit in between each big coat. Everything felt flawless and looked perfect. Scuffed it up with 400 again, sprayed Duplicolor's high gloss black lacquer, and bam, All seems where bondo meets EFS stuck out.

So, if this would not have happened, my next steps were going to be a couple more color coats, then clear coat, wetsanding the clear coat and applying a mild rubbing compound and polish. But obviously at the moment I'm being cautious moving forward because I don't know what to do to get rid of the seems.

Is it a matter of sanding the edges down to wood and building it up again? Or if I proceed with more color coats, will they eventually even out?? I'm just surprised because everything felt great prior to color, now as you can see things look unacceptable, especially since the clear coat will probably show that off even more...

 

[gmichael]

I like to start with a 50/50 mix of yellow glue & water for my first coat/primer.
You may not want to sand it down and start over though. If not, you could put a few layers of clearcoat on, and then paint over that.

6 or 1/2 dozen I guess.

 

[Tungsten06GT]

I like to start with a 50/50 mix of yellow glue & water for my first coat/primer.
You may not want to sand it down and start over though. If not, you could put a few layers of clearcoat on, and then paint over that.

6 or 1/2 dozen I guess.

I don't think I want to sand it down and start over... But here's where I'm at exactly. The side in the picture is the only side I have painted, along with the bottom. All other sides are only primed...

When you say a couple layers of clearcoat, then paint over that, you mean in the current state it's in over the color?

 

[annunaki]

You should have used glazing putty over the bondo, it fills the tiny holes and sands very well.

Sealing all the seams with MDF is crucial since it soaks up any moisture like a sponge, then expands. That is what you may be seeing.

With MDF the best thing to do is to heat the inside of your enclosure to around 100 degrees after the primer & paint are applied or between coats. Assuming you have of course sealed the seams with some sort of sealer.

 

[Tungsten06GT]

You should have used glazing putty over the bondo, it fills the tiny holes and sands very well.

Sealing all the seams with MDF is crucial since it soaks up any moisture like a sponge, then expands. That is what you may be seeing.

With MDF the best thing to do is to heat the inside of your enclosure to around 100 degrees after the primer & paint are applied or between coats. Assuming you have of course sealed the seams with some sort of sealer.

That glazing putty seems pretty useful. What I think was going on is that I had built up the bondo and it was still just high enough to create that ledge that you can see there on the pic. So last night, I went back and sanded all of the edges down and feathered them in.

I think I'm going to shoot another coat of primer over the whole box. Check for spots to use the glazing putty, smooth it, then prime again and hopefully color will work out alot better...

 

[annunaki]

The bondo still seemed high in your photo. Sanding it down would be advised. Keep the pics coming.

 

[Tungsten06GT]

So yeah I decided to sand down the edges and level everything out again..

I think will try to shoot another coat of primer tonight, then check for any spots to hit with the glazing putty, then another coat of primer, and go from there; hopefully I get things a little more level this time.