Guide Coat - First Sanding

Our first guide coat process is almost complete and it took a lot of hours to get here.  Thankfully Ty came over and spent many of those hours with a sanding block in his hand.  While sanding, it's amazing to watch how the guide coat identifies everything that's less than perfect.  Here's an example:

The next four pictures show the progress made on the drivers side roof.  The only difference between these pictures is the amount of block sanding that occurred.  After a few swipes with the sanding block lots of irregularities are identified including a significant run in the primer located near the door opening.

A few minutes later many of the irregularities are gone except for the run and a few pits.

A little more sanding and the run is gone.  A few of the pits remain and we now see some irregularities near the door opening. 

Fiberglass is beginning to show through so we have to stop sanding.  The roof is very smooth with minor irregularities that will be fixed with the next coat of primer.

Looking at other areas of the car we can see that this area needs another heavy coat of primer.  The circled spot identifies an area that needs a little Bondo.

Areas marked with an X also require a little Bondo.

This is a repair that was recently made when we found an air bubble in a rivet hole.

These irregularities occurred when we installed the wheel well inserts.

Except for the X's, this area will only require another coat of primer.

The left rear looks great except for a few little shallow areas.

The primer in this photo is very thin but the surface is very smooth.

This is the left rear window area.  The pattern you see are depressions made by the body mold used back in 1963.  They are so shallow they can't be felt but the guide coat tells us they are there.  Our next coat of primer will fix these "irregularities" as well.

More primer, more guide coat and more sanding is next but we only have to do the areas that need it, not the whole car.  We'll still have to make another paint booth though.

As always, thanks for watching.

Guide Coat 101

What the... ?

You gotta be kidding me!

OK, here's the deal.  A Guide Coat does two things.  It insures flat surfaces and it identifies low spots.  The process requires a contrasting paint lightly sprayed over primer followed by block sanding.  We want to leave as much primer on the car as possible but we also want to remove as much as necessary to get a flat surface.  To achieve this we only block sand until the guide coat is removed or until we expose fiberglass.  When either one of these occur we stop sanding and move onto the next area.

Lets get started.  After block sanding this fender for just a few minutes we have mostly flat surfaces (green) and a few low spots (guide coat).  A few more swipes with the sand paper should remove several of these low spots.

And that's exactly what happened.  The front part of this fender is very flat and smooth.  Any thin areas of primer will be corrected when we shoot the car with the next full coat of primer.

The rear part of the fender will need additional work though.  We have low spots and we have exposed fiberglass.  Since we can't sand this area any further we will probably apply a thin coat of Bondo to correct.

These low spots are super shallow and will be filled in with the next coat of primer.

Click on this picture and check out the results.  Do you think the next coat of primer will fix the low spots or do you think they need a little Bondo?  It might be a combination of both. 

The front is turning out very nice.  The raised center section may require a little Bondo.

Nothing major back here.  The next coat of primer should fix these imperfections.

There is a lot left to do including the door jambs, drip rails, hood jamb, window jambs, and everything below the center line.  When we are done we will shoot fresh primer on the whole car again followed by more Guide Coat.  We will continue this process until all the surfaces are flat and all the fiberglass has primer so expect several postings about guide coating.  One thing for sure is the results are already pretty awesome.

Thanks for watching.