[April 28, 2007]

I only had 6 or so parts left to debur tonight. I thought I could blow through them in no time. This project has a funny way of making things you think will take no time into taking twice or three times as long as you think it will, as well as making things that you think will take a while into a non event. The flanges of the F-711 and 712 bulheads aren't radiused at all. It took forever to use a needle file to round all of these things off - I think I counted about 40 corners to round off on each of the 4 bulkheads.

Here it is - a pile of parts that looked identical to how it looked the other day, except with 7 hours of work being the difference. I am thinking I will need to break this up into two priming sessions, just because of the shear bulk of parts here.

Another issue I am contemplating is two of the bulkheads have parts exposed to the interior of the cabin, meaning it will eventually need a topcoat. The issue with the topcoat is AKZO don't take a topcoat without being sanded down. My options now are to 1) not prime the parts that are exposed, 2) prime everything with AKZO and sand later, 3) prime everything not seen with AKZO, and everything exposed with GBP-988. I have asked a couple of builders out there for their opinions on what I should do.

Later tonight, I got a response from Dan Checkoway on his opinion on the matter:


Good thing you're askin' about this. Don't prime anything in the cabin...just like you're hinting at, you'll have to reprime it before you paint it. And for that matter, don't paint anything you don't HAVE to paint either -- at least until you know what type of interior you're going with.

If you do what most people do and have some sort of interior panels/covering, any paint there is just wasted weight & money. I'm glad I did paint mine since I have no interior to speak of (that was one way I compensated for a heavy engine/prop combo...no regrets), but the stuff I primed with AKZO had to get sanded down. What a waste of time...

Yeah, if you use GBP-988 or any of the other self-etchers, they do need a top coat within X hours, otherwise it's the same deal as AKZO...sand/clean & reprime.

It's definitely easier painting the cabin when things are wide open, so "now is the time" so to speak. But what now is really the time for is figuring out your interior details. Knowing that, you'll know what needs paint & what doesn't. And knowing that, you'll know what not to bother priming.

The cabin isn't exactly a high moisture area. I think a lot of builders overdo it in this dept.

Hope this helps. Best of luck with the rest!

)_( Dan

With that said, here is my take on how to proceed - on the seatback bulkhead, I will prime the lower part that is under the flooring (aka, won't ever be seen inside). Above that, I will prime the mating surfaces only with GBP-988 and leave everything else unprimed. The nice thing about using the spraycan primer on the parts that will get a topcoat is that any overspray will be easily removed with a solvent, so I don't need to sand it off. So that is my plan of attack.


Last Modified: August 13, 2023