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Wed Aug 04, 2004 6:29 pm

What final grit of paper to use,(wet sand) prior to final paint. Also does anyone have any advice on best PPG enamel to spray over the K36??.. :?:[/img]

Wed Aug 04, 2004 9:31 pm

Final wetsand grit is 600. Why not spray a basecoat/clearcoat its a lot better,and besides I don't think PPG still makes Enamel, I forget. Man I haven't sprayed that in 20 years. They have a single stage, and Polyurathane but not and synthol or alkayd emanel, I don't think.

Wed Aug 04, 2004 9:33 pm

OUCH!!

Did you say you intended to wet sand your primer? Water and primer are not a good mix. Dry sanding is better. 1000 is too fine and never any coarser than 400. Too fine and you won't leave enough 'tooth' on the primer to assure good adheasion of the top coat. I have a box of 600 I use for such things.

DBC base and DAU75 clear will give you a top quality finish. If you are looking for a show finish, PPG has a couple of other clears that will give a little better gloss and depth at the cost of being less resistant to UV. Check with your dealer on them.

Thu Aug 05, 2004 4:36 pm

Using the k36 as a primer surfacer...isnt it waterproof???...Thats what the paint shop told me??.......What about the DAR polyurethane acrylic enamel....have you sprayed any of that as a single stage??....or should I spray clear coat on it for colorsanding??.....it's just a driver car painted in an old cleaned out garage, not a paint booth??...any help would help...thanks...

Thu Aug 05, 2004 4:41 pm

I also sprayed PPG DP74LF as a sealer prior to the PPG k36 with the K201 as a primer surfacer??.....

Thu Aug 05, 2004 6:33 pm

I always wetsand my high build primer (although I use K38). I guidecoat with a mist of paint from a Krylon can so I can see my progress. Knock down the high stuff with 400 or 500, then finish off with 600. You could drysand it, but man, would that clog the paper.

Thu Aug 05, 2004 8:55 pm

K36 is not a 2k product and I would not trust it to be waterproof. The danger is not with the primer itself but with any bodywork underneath. If you epoxied then filled, the filler could absorb water. Nothing that can't be corrected by a couple of days in the sun but a potential hassle. The K38 is a fully catalyzed primer and is likely really waterproof.
As far as the sandpaper loading up, I recently came across a box of 600, brand name Abranet. It is like a fine net material impregnated with abrasive. It doesn't load up hardly at all. On a DA, every now and then, you just lift the sander and spin the disk. You see a cloud of dust as it cleans itself out. There is a note on the box about being sure your sander is in full contact with the surface before you start it. If you try some, heed that warning - it will bite in and gouge if you don't. The second time you make that mistake, you will forever remember the problem. :?

Fri Aug 06, 2004 10:40 pm

K-36 is a 2K product. 2K simply means two components and both the 36 and the 38 uses the k201 as a hardner. Therefor they are thermal set and not thremal plastic like a lacquer product. Also you can wet sand or dry sand both the 36 and the 38 with no problems. Check the P bulletins and see. The k38 costs more that the k36 but the k36 sprays on smoother due to the option to add reducer. The mixing ratio for the k36 is 5-1 and the k38 is 4-1. The k36 has a slightly higher film buils than the k38. Both work but when you are looking for cost than the k36 is the one you want for your money.

Fri Aug 06, 2004 10:59 pm

If you seal it.. wetsand all you want.....

Sat Aug 07, 2004 4:14 am

My impression from the p sheets is that K-36 is simply a single stage with a hardener additive and K-38 is a fully catalyzed paint. To me, 2K paint is only the fully catalyzed version, not a single stage with hardener added. I am not super aware of all the newer paint technologys so if I am misunderstanding something here, fill me in.
My point on sanding is simply, if you have unsealed filler under your primer, use a waterproof primer or dry sand. Dry sanding recommendation applies only to that specific combination

Sat Aug 07, 2004 9:53 am

I thought you guys might have some ideas?......I guess the options and the complication has risen......That's why I was wondering if you guys had any experience with the paint.....if you use the k36 as a tinted primer surfacer, then the ratio changes once again to 2:1:0.5 (I was planning on leaving the car in primer,therefore I have a gallon of tinted k36)...now I'm just going to spray it.....so no one has used the PPG DAR Delstar/Delthane I was going to use that for good matching?.....Thanks for your help

Sat Aug 07, 2004 11:46 pm

That is a single stage paint which means direct gloss and no clearcoat is needed. I didn't know that PPG still makes that paint line. The DCC is their singlestage paint. Here it hasen't been available for at least ten years. Also what do you mean when you say good matching?

Sun Aug 08, 2004 9:43 am

I'm trying to match the color to 68 royal red....the interior of the car is in great shape, so I wanted to match the color...to paint the outside only, it's going to be just a daily grocery getter.....some paints do not come up for a paint code to make the color??....atleast that's what the dealer told me??......I guess the paint police is in force on hawaii, not as strict here??...should be good paint though....

Sun Aug 08, 2004 3:09 pm

Do you have the paint or will you have to buy it? If you have to buy it why not check if the paint store can mix it up in DCC.

Sun Aug 08, 2004 6:29 pm

I still need to buy the final paint.....that's a good idea.....I will check with them....what do you think the advantages are of the DCC ......It's not the omni ppg line is it??......I think they said they could not get as close to it with the omni.......I wanted to spray clear on it, due to the dirty paint conditions ;i.e (garage)....They said I could clear the DAR but it was optional?......I need to paint this thing before summer leaves... :lol:

Sun Aug 08, 2004 6:40 pm

It looks like the p sheet says DCC can be coated with a couple of different PPG clears.

Look here:
http://www.ppg.com/cr-refinish/phase1/frmFindProduct.asp

Sun Aug 08, 2004 11:49 pm

Big Jim is correct you can spray some clears over. I would use the DCU2002 with the DCX 61 hardner. Just one note if the color is a solid you must wait for two hours then spray the clear. If its a metallic color then you must wait four hours, thats so you will not have mottling which is the metallic flakes moving upon spraying of the clearcoat.

Mon Aug 09, 2004 6:11 pm

Thanks for all of your help you guys.....I am going to the paint shop on wednesday!!!....starting final sanding (dry) with 400 *hand*....no DA's....coming out real smooth.....it's a solid factory color.....royal red.....*wish I was spraying some sort of metal flakes*.....I'll have to post some photos as soon as the tape comes off!!!....I think I will clear it also!!...Thanks for your ideas....

Mon Aug 09, 2004 6:59 pm

Man havent used k36 in years out here in California.

Mon Aug 09, 2004 8:46 pm

Just one note,hope that you are using and sanding block to sand and not just your hand because the surface may come smooth but not straight.