CantZme Posted March 13, 2009 Share Posted March 13, 2009 I am about to shoot my 260z with pcl self etching primer and have a few ?'s before I begin. I have filled some of the body with bondo and used a glazing putty over the filler. The shop I bought my supplies from sold me everything including the paint and clear. I was given PCL polyprimer and told to shoot it over the PCL self etching primer and then paint; however, I have been told from a few people that a urethane primer must be used over the poly primer before paint. I have contacted the shop and the salesman says that it isn't necessary. What's the deal here? I really don't want to screw up my first paint job. I also asked him about the thickness of the poly primer and he told me to put 20% reducer; however, some have told me not to reduce the poly primer and just use a large nozzle gun. This would pose a problem because I only have one gun with a 1.7mm nozzle and it cannot be changed since it isn't manufactured. Is it a bad idea to reduce the poly primer for the 1.7mm nozzle? Must I use urethane primer over poly primer? Please help!! Quote Link to comment Share on other sites More sharing options...
ZR8ED Posted March 13, 2009 Share Posted March 13, 2009 My paint experience is OEM, with some refinish, so take my knowledge with some salt ok? "poly" primer and "urethane" primer is the same thing. Some products are called "poly" primer, "urethane" primer, and "polyurethane" primer. Same tech different names depending on product branding. I would really hope that the paint counter guy sold you a "system". That is a primer that matches/compatible with the topcoat, that matches/compatible with the clearocoat. I am obviously biased, but as long as you are using a total "system", you will be just fine. Yes some paint systems are better than others, but that is usually up for debate, and is often based on experience with one brand or another. As for reducing the primer, what does it say on the can/tech sheet? if it says it is prepared ready to spray, then just spray it. Tweaking "ready to spray" products in my opinion is done to compensate for specific non ideal spray conditions, and/or compensate for poor operator technique. Good luck! Quote Link to comment Share on other sites More sharing options...
z-ya Posted March 13, 2009 Share Posted March 13, 2009 I'm using 2K urethane (high build) primer after the filler was block sanded. It works great in filling all the filler sanding scratches. The first coat I mixed 4-1, then sand it with 150 grit. Then I put another coat with 4-1-1 ratio and sand with 320 grit. The final primer coat is mixed to 4-1-2 and it is ready for the color coat. So basically you are using the 2K primer as a sealer when you mix it 4-1-2 (primer-hardener-reducer). The 2K urethane primer sands easily, and and you end up with a super smooth surface for the color coat. I'll post pics when I am done. Pete Quote Link to comment Share on other sites More sharing options...
CantZme Posted March 13, 2009 Author Share Posted March 13, 2009 thanks for the responses guys, but It says that it's a polyester hi filler primer surfacer, so I don't think it's urethane. The can of the primer states that it doesn not need to be reduced, but to use acetone if reducing is necessary. It is smart to reduce this primer enough to shoot through a 1.7mm gun? Quote Link to comment Share on other sites More sharing options...
geezer Posted March 13, 2009 Share Posted March 13, 2009 Every different brand name or product from within a particular company will have different formulations, based on intended use, price range, etc. Therefore the answers to your questions can best be addressed by the company who developed the product. Other than that, I can only echo what ZR8ED has told you, it is best to use a "total paint system" to ensure compatibility and adhesion between the components. If for some reason you cannot get this information from your paint supplier, your best bet is experimentation on a few test panels. If you are forced to thin the product for spraying, only thin the amount you will be immediately using. If the test panels don't work out well, you will have to go beyond the salesman you have been talking to, in order to get the relevent information on the products you are using. Good luck! PS - I have successfully experimented using different brands and I also have had catastrophic failures. Quote Link to comment Share on other sites More sharing options...
ZR8ED Posted March 13, 2009 Share Posted March 13, 2009 Ok Polyester primer is different. Very high solids, sprays on very thick, more difficult to sand than an epoxy primer. This should be used on "rough' body work" ie if the panels are good and pretty straight, then this would be over kill. It is a high hiding primer. "I was given PCL polyprimer and told to shoot it over the PCL self etching primer and then paint" Just use what you have and don't worry too much about it. It sounds like you have what I call a "system", and you should be just fine. Not sure about the tip size, there are lots of types of spray guns, tips, operation pressures, flowrates etc. Too many variables to comment. If you are really worried, try painting a small piece of scrap sheetmetal as a test. If it "chunks" up or nothing comes out, you will know. Sorry but that is the best I can offer from behind my keyboard. A couple of interesting reads. http://www.autobody101.com/ http://www.autorefinishdevilbiss.com/index_2.php http://www.neilslade.com/Papers/Painting.html Quote Link to comment Share on other sites More sharing options...
z-ya Posted March 13, 2009 Share Posted March 13, 2009 thanks for the responses guys, but It says that it's a polyester hi filler primer surfacer, so I don't think it's urethane. The can of the primer states that it doesn not need to be reduced, but to use acetone if reducing is necessary. It is smart to reduce this primer enough to shoot through a 1.7mm gun? If it is your first coat of primer, then I would not reduce it, but only add the correct ratio of hardener. Keep adding coats and sanding until you are happy with the primed finish. Then I would reduce it with 1 part acetone (like 4-1-1) for use as a sealer. Then the color coat. Pete Quote Link to comment Share on other sites More sharing options...
palosfv3 Posted March 13, 2009 Share Posted March 13, 2009 thanks for the responses guys, but It says that it's a polyester hi filler primer surfacer, so I don't think it's urethane. The can of the primer states that it doesn not need to be reduced, but to use acetone if reducing is necessary. It is smart to reduce this primer enough to shoot through a 1.7mm gun? The comment to reduce with acetone concerns me. Almost all of todays quality systems do not use straight acetone to reduce. If this is a product like "Feather Fill " , take it back and get a refund. The general rule is if it takes more than 3 coats of primer to fill the scratch, blemish or pit , it doesnt belong on the car. This may sound extreme especially to someone doing a first paint job but you will quickly see the benefit of the extra effort inthe quality of the repair. Did you take the car down to bare metal ? Any old original finish should be. It will make a huge difference in how everything works and lasts. The manufacturer of the paint you purchased should have a web site with all the necessary tech and data sheets . Make sure you take the time to look them up and follow them . Dont rely on what others have done or think should be done . Rely on the correct info put together by the chemists and engineers that designed the product. Could you provide a little better info on the product you purchased ? I've been auto body business for 40 years and never heard of PCL brand. Quote Link to comment Share on other sites More sharing options...
CantZme Posted March 14, 2009 Author Share Posted March 14, 2009 the product is made by pcl automotive and this is the tech sheet, http://www.pclautomotive.com/Product_Profile/polyprimer013007.pdf. I shot 2 coats of the poly primer today; however, the areas that had filler applied to them are lighter and visible through the primer. 2 coats of etching primer were shot first and then the poly primer was shot. I added 10% urethane reducer to the primer as a nearby body shop advised me to do. Should I add shoot another coat of primer? Quote Link to comment Share on other sites More sharing options...
z-ya Posted March 16, 2009 Share Posted March 16, 2009 Have you sanded the primer? If you sand it with 320 grit you should not see where the filler is. Once you get the sanded primer layers the way you want, then spray a sealer coat. Pete Quote Link to comment Share on other sites More sharing options...
CantZme Posted March 20, 2009 Author Share Posted March 20, 2009 one is polyester and one is urethane, they're very different Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.