Author Topic: Primer (Read 4079 times)

Greg L Bahrman · « **on:** May 09, 2012, 06:51:22 PM »

What brand primer should I use under Sig paint

thanks

Randy Powell · « **Reply #1 on:** May 10, 2012, 10:59:29 AM »

Greg L Bahrman · « **Reply #2 on:** May 10, 2012, 09:24:37 PM »

Randy,
Sure your probably thinking, what a stupid question.......Well that seems like the logical answer, except if you go to the Sig Web site you cannot find primer listed anywhere. I was told by others that they don't make a primer, is this true?

What has everyone been using

?

Dick Pacini · « **Reply #3 on:** May 10, 2012, 09:31:46 PM »

Type in primer in their search.

SIGPB001 SIG PRIMER BOTTLE 2 OZ EACH $1.99

Andrew Hathaway · « **Reply #4 on:** May 10, 2012, 10:04:20 PM »

Quote from: Dick Pacini on May 10, 2012, 09:31:46 PM

Type in primer in their search.

SIGPB001 SIG PRIMER BOTTLE 2 OZ EACH $1.99

If you order that part number expecting paint, you'll be disappointed. That's a small plastic bottle intended for holding fuel for priming an engine, not for a paint job.

Dick Pacini · « **Reply #5 on:** May 11, 2012, 01:28:03 AM »

Oops, my mistake. Sorry.

Avaiojet · « **Reply #6 on:** May 11, 2012, 02:15:10 AM »

If you sealed the model with dope. Applied covering with dope, and the paint colors were also dope, why would you need a primer?

Especially if it's not dope.

Charles

Derek Barry · « **Reply #7 on:** May 11, 2012, 04:26:00 AM »

This is what i use. I use it under Sig and Brodak. I have never had any problem and it is very good at filling in all the little imperfections. It sands very easy too, just give it a few days to get good and hard. I have sanded it the next day but I recommend waiting a couple.

Derek

FYI, my process is: Nitrate, (usually right out of the can without adding thinner, this will seal the wood faster and prevent excess weight) I sand it flat between coats. I apply the silkspan with Nitrate, then I move on to Sig Light Coat. After the Silkspan is on I never use a brush again, everything is sprayed out of a gun. once it is all sealed with light coat I do a filler coat (zinc powder mixed with clear). this is sanded smooth and by this time most of the orange peal should be gone. I seal that with one more light coat of Sig clear (light coat) then I spray the primer. sand the primer and you are ready for your base.

Derek

Allan Perret · « **Reply #8 on:** May 11, 2012, 06:15:27 AM »

Quote from: Greg L Bahrman on May 10, 2012, 09:24:37 PM

Randy,
Sure your probably thinking, what a stupid question.......Well that seems like the logical answer, except if you go to the Sig Web site you cannot find primer listed anywhere. I was told by others that they don't make a primer, is this true? What has everyone been using ?

Sig does make a primer, its called Sanding Sealer. Its at the bottom of the dope page.
http://www.sigmfg.com/cgi-bin/dpsmart.exe/MainMenuFV4.html?E+Sig

This is SIG's description:
"Sanding Sealer is basically our Lite-Coat low-shrink butyrate dope with special light weight, easy-to-sand fillers added that make it the perfect surface primer for a dope finish. Two coats of Sanding Sealer, put on after your initial two coats of clear dope, then sanded thoroughly when dry, will provide an ultra-smooth base for the color dope. Sanding Sealer is completely compatible with all other Sig butyrate dope products."

You can make your own using the Sig clear dope you already have by adding talc powder, cornstarch, or zinc sterate (Aero1 from Randy Smith).

steven yampolsky · « **Reply #9 on:** May 11, 2012, 12:01:48 PM »

Quote from: Greg L Bahrman on May 09, 2012, 06:51:22 PM

What brand primer should I use under Sig paint thanks

I use a technique very similar to Derek's so the primer question applies to the phase after Nitrate. For primer, I use Buterate clear(any brand you have is fine) with a few drops of black paint to give the mixture gray tint. I also add Zinc Stearate or Corn Starch to the first two coats after applying silkspan. Zinc is lighter and more expensive than Corn starch. Corn starch is heavier but sands much easier(more like powders off thank sands).

Allan Perret · « **Reply #10 on:** May 11, 2012, 03:37:40 PM »

Quote from: Derek Barry on May 11, 2012, 04:26:00 AM

This is what i use. I use it under Sig and Brodak. I have never had any problem and it is very good at filling in all the little imperfections. It sands very easy too, just give it a few days to get good and hard. I have sanded it the next day but I recommend waiting a couple.

Derek

FYI, my process is: Nitrate, (usually right out of the can without adding thinner, this will seal the wood faster and prevent excess weight) I sand it flat between coats. I apply the silkspan with Nitrate, then I move on to Sig Light Coat. After the Silkspan is on I never use a brush again, everything is sprayed out of a gun. once it is all sealed with light coat I do a filler coat (zinc powder mixed with clear). this is sanded smooth and by this time most of the orange peal should be gone. I seal that with one more light coat of Sig clear (light coat) then I spray the primer. sand the primer and you are ready for your base.

Derek

This Nason Ful-Fil, is it a 2 part primer, or thinned with lacquer thinner ?

Randy Powell · « **Reply #11 on:** May 11, 2012, 05:34:33 PM »

OK, I use whatever lacquer I'm using (Randolph's, Certified, whatever), mix in a little white, a few drops of black and a filling material (talc, zinc sterate, cornstarch, whatever you're using). Shake it up and then thin it enough to go through my primer gun.

Alternately, I use something like K-36 2 part primer (not unlike the Nasson Derek is using). It has the advantage that once it catalyzes, it doesn't seem to mind lacquer being put over the top of it. Sands very easily, but has the drawback that you really have to sand as much as possible off because it ain't light.

Bill Little · « **Reply #12 on:** May 11, 2012, 05:40:35 PM »

I would guess I am evenly divided in using zinc sterate in clear or Dupont automotive primer. The auto primer is heavier, like Brother Randy says.

BIG Bear
RNMM/AMM

Derek Barry · « **Reply #13 on:** May 13, 2012, 05:07:41 PM »

Quote from: Allan Perret on May 11, 2012, 03:37:40 PM

This Nason Ful-Fil, is it a 2 part primer, or thinned with lacquer thinner ?

Dupont 3608s or 3602s. This is a lacquer thinner.

Derek

RandySmith · « **Reply #14 on:** May 13, 2012, 06:00:17 PM »

Zinc Sterate and dope is the best lightest and easiest to sand primer I have ever used, and I have tried most all out there. For being light and a cinch to sand it is tops.
I have used it with both nitrate and butyrate dopes, I spray it on thinned 100 % then without sanding look for the bad spots, brush more full strength over the bad spots only. The sand it off.
Adding a few drops of black will help to see any flaw

Randy

Bill Little · « **Reply #15 on:** May 13, 2012, 06:43:45 PM »

Learning to "candle" the surface is critical in removing the bad spots.

BIG Bear
RNMM/AMM

RandySmith · « **Reply #16 on:** May 14, 2012, 11:48:25 PM »

Learning to sand , flat, is also extremely important, use blocks where you can, and use flexible foam pads also around curves, this stops the gouging and all of the tiny dips you see when people just hand sand.
The grey primer spray will show most every flaw instantly.

Randy

Douglas Ames · « **Reply #17 on:** July 11, 2012, 10:54:37 PM »

Hand sanding (paper in your hand) is the worst thing you can do to a flat surface. Like having 4 rat tail files wrapped in 50 grit...you'll just makes divots.
Rubber blocks and custom pine blocks are worth the effort. Sand at a bias to level and remove material then finish with sanding with the grain to smooth. Keep your paper clean! If it loads up it will gouge.

RandySmith · « **Reply #18 on:** July 12, 2012, 01:20:18 PM »

you can buy the black soft foam bendable / shapeable... sanding blocks and pads at most all auto paint stores, they are worth the money many times over, I have found the Gold color 3m paper to be excellent at removing filler or sealer in 400 grit, Be careful if you use Zinc Filler as there are many grades, some do not sand well, The stuff I use is the easist to sand of any filler / sealer I have ever used or seen, comes off like rubbing chalk with the production 400 gold 3M.

Randy

Balsa Butcher · « **Reply #19 on:** July 12, 2012, 04:35:10 PM »

In addition to foam sanding blocks I use blocks I have made out of scrap balsa-usually 1/2-3/4". Unlike blocks made out of harder wood they they won't gouge the balsa if you slip and are light which gives one a good feel for the amount of pressure being applied. They can easily be shaped to conform to tight spaces or wing/stab filets. Primer: Sig Polar Grey, a bit of silver and a tablespoon of Aero Products ZS filler. Thin, spray, sand, sand, sand.

Dennis Toth · « **Reply #20 on:** August 28, 2012, 01:31:22 PM »

Guys,
After the filler/sealer what have you used for a blocking coat? The guys that use silver (Windy) keep sanding the silver until they get it flawless then do a final finish coat before color. I did that and found silver is hard to cover. White, as in primer, is very heavy so you would have to apply then sand and touch up spots you go through. Is there a better approach?

Best, DennisT

Author Topic: Primer (Read 4079 times)

steven yampolsky