Robert's recommendation on Primer

[Mike Griffin]

I remember a conversation we had on here not too long ago about primers.  Robert (aka Sparky) was recommending a product you can find at NAPA.  I am not sure if it was here or on another forum but I do want to say something about this product.  You can get it at NAPA Auto Parts and it is called COLORLINE .  On the back where the bar code sticker is right about the bar code is DC540 Gray Primer.  It dries so fast you can actually see it drying.  You can sand it after 15 minutes and Robert tells me that 400-600 grit is best over Polyspan open bays.  I am using it on my new Electric Take Apart Ringmaster before I paint.

I have tried a lot of primers but Robert was right..this is the best primer I have ever used.

Thanks Robert

Mike

[Ward Van Duzer]

But can you dope over it? Or do you use auto paints or:

W.

[RC Storick]

But can you dope over it? Or do you use auto paints or:

W.

Yes I have used all the dope brands over it. Except Aerogloss. Its works for all type paints and once you use it you will never use anything else.

[wwwarbird]

 After the recent discussion on the Napa primer I almost tried it on my current Challenger project, but I chickened out. I usually don't even use primer, so I went with the "if it ain't broke don't fix it" program to not risk any issues. I might have to try the stuff on the next one though.

[Mike Lauerman]

I've tried most of 'em, and this is good news. (at last!) The previous 'good one' I used was 'sandable primer', yes, 'sandable', but not always coverable.

That's the important thing about 'primer'. Glad to hear this, Sparky. Following your finishes on your planes, I'll take your tips any time.

I have a NAPA account...

[Mike Griffin]

I have a report for you guys about this primer.  I just finished sanding my Ringmaster completely after applying this primer.  I used 400 grit on the solid balsa surfaces and 600 on the open bays (the wing was covered in Polyspan) and I have NEVER EVER had that smooth of a surface ready for paint since I have been building.  It dried in minutes but I waited an hour before I started sanding.  Before you sand if you run your hand over it, the surface feels kind of gritty but when you start sanding it smoothes out to a slick smooth surface.  I cannot remember having such a smooth surface getting ready to paint.

Note:  Here is how I did the preparation on the solid balsa surfaces and On a Ringmaster that is everything but the wing.

I sanded all solid surfaces as smooth as I could ending with 400 grit.

I then took Minwax Polyurethane right out of the can and brushed two coats of it on the surfaces, letting it dry overnight between coats.

I then sanded all the surfaces down as smooth as I could get them.

Then I took some Dap Vinyl Spackling compound and mixed it with enough water in a glass to get a consistency of Pancake Batter.  Get it as smooth as possible.

Brush a coat of this on and let it dry good.  In the summer outside it will dry quick. I have applied a second coat in as soon as an hour.

Sand the first coat smooth and then apply a second coat of this slurry and let it dry.

Sand again as smooth as you can get it.  I usually start with 180 grit, go to 220 and then to 400 for the final sanding.

Then spray your primer (NAPA COLORLINE) and sand it as I explained above.

Paint with anything you want to paint with.  I will probably use Duplicolor and spray a urethane clear coat over that.

Mike

Oh PS...I covered the wing in Polyspan and applied the first coat of Nitrate dope right out of the can and did not thin it.  The second and third coats were thinned 50/50.  I lightly sanded with 400.  Then I put two filler coats of 50/50 dope with zinc steerate and then sanded again LIGHTLY with 400 and applied my primer.  Sand the primer with 400 or 600 grit.  I did the edges and the center sheeting area with 400 and the open bays with 600 and as my grandpappy used to say , "It is slicker than a minnows peter."   Thats an old country saying.. 

[wwwarbird]

 Sparky,

 Once you have your polyspan attached intially, what mix and how many buildup coats do you normally go with before shooting primer?

[Dan Bregar]

Does this stuff come in white ?  Or is grey  it ?  Reason I ask is I like to use bright yellow and it goes best over a white base. 

[Mike Griffin]

It is gray
Mike

[RC Storick]

They sell white also. I have never used it.

[RC Storick]

Attach covering. 2 coats 50/50 and sand. 2 more coats 50/50 and then prime. I try not to fill open bays too much,just a dust coat. It takes me 6 cans to do a full size ship. Most all of it is sanded off. It does not matter how much you put on or how its sprayed. What matters most is how much is taken off. A great finish can be applied with a bug sprayer if your willing to sand. Its all in the sanding!

As a side note. On my crossfire I had a clear issue on the flap so I sprayed it with Krylon Chrystal clear. So far you cant tell its any diffrent than the auto urethane. Time will tell.

[Mike Griffin]

Sorry Dan.. I did not see the white.  I used the Gray

Mike

[wwwarbird]

Attach covering. 2 coats 50/50 and sand. 2 more coats 50/50 and then prime.

 Thanks Sparky, I assume you're brushing the 50/50?

[RC Storick]

yes

[wwwarbird]

 Got it, thanks!

[john e. holliday]

The guy t the NAPA store reccommended the grey primer that I have been using for several years.  Ever since Ruty Brown told me about the two part auto motive clears.   As stated it does not matter how much you put on, it is how much you take off.