A primer on primer

[bharaway]

I am beginning work on the body panels of my 55 Century 2dr. I  was wanting the sage advice of those having finished the race regarding the best first "on bare metal"  primer to use. I would like to use a non- isocyante primer that I can shoot in my garage. It would be nice to get yall to weigh in on building primers as well. I am thinking epoxy primer 2k with no chromate to "cover and protect" each part or panel until I get around to completing the body work and begin the build up primers for block sanding. Quality and safety are #1, availability is #2 and price 3. I have heard some say use an etching primer first then build. Also, does anyone have an opinion about the slick-sand product for building and block sanding?  Thanks for the help. 

[Mudbone]

I am not a professional, but I do know that the local body shop will use different products and procedures than the hobbyist or the restorer does. I use PPG DPLF epoxy primer over bare metal. PROS: It sprays real easy. It is an excellent rust inhibitor and it does not have to be top coated for long term protection. You can also use the same product as a sealer by adding thinner. (No additional products to buy for sealer) It also comes in different colors if you are using it as a sealer. CONS: It is expensive. You have to use what you mix. You must scuff and re-coat before any additional top coats if it sits more than a week. I am sure there are less expensive products out there that are similar, but PPG is sold locally. You must have good ventilation and good quality mask or fresh air system. (If you can smell the paint through the mask it is not working)   Mud

[old-tank]

If the parts will be stored for a long time the epoxy primer is the best.  If the bare metal to paint time is short and the parts are stored dry and indoors, then there are other options.  I use Ospho or etching primer on bare metal followed by Lacquer primer to build along with various body fillers, puttys and glazes as needed.  The only non-isocyanate top coat is lacquer which gives good results but will fail in 5-10 years.  Catalyzed acrylic enamel will have the same look of lacquer with good durability especially for a car that will lead a sheltered life.  I have found that the most important thing no matter what system you use is to let the substrate applications go through at least a day of temperature variations before the next  application.  Use one brand of products and be sure of compatibility of substrates and top coats.

Willie

[NTX5467]

Several years ago, Kevin Tetz on the cable show "TRUCKS" has done several segments on paint and body work, including which primer can be the best (with one graphic example).  You can probalby find those videos on YouTube or the website for "TRUCKS".  Might even be some on the Eastwood website, too.

 

The comment about what a "production shop" might use compared to what a "hobby person" might use is VERY valid.  Automotive coatings can tend to be an ever-changing landscape!  Especiallly for the OEM suppliers.  What that can mean is that if you are using one company's paint system, it could change sometime in the next year or so . . . or move downward in the pecking order of "new" and "readily-available" (which the local suppliers have NO control over!).  Therefore, to hopefully ensure compatibility of the primer components with future products, using the newest might be better (as it might have a longer, total production life cycle).

 

DO keep a diary of what products you do use for what sections of your activities.  That way, should the product line of available products update, you can check for compatibility with newer products.

 

Seems like there is a website from which paint products (all phases) can be purchased?  I suspect they have a complete line of products (for lacquer, acrylic lacquer, acrylic enamel, catalysts as applicable, primers, etc.), but THEN they are THERE and you are "where you are" geographically.  IF you can find a local supplier that can mimic their product availability AND provide you with some "hands-on" guidance, so much the better as local support can be better than talking to somebody at the other end of a phone line.

 

Some of the major paint suppliers also do regional training seminars, which might be interesting to attend.

 

As mentioned, having a "temperature/humidity-stable" environment in which to work can be just as important in body shop work as it can be in the building trades industry.  It might also be highly recommended that you have a separate place to do the spray work.  If not, you'll probably be dusting primer from places you didn't know it could get to. 

 

One OTHER minor detail, which can be variable, is the limit of how much a "private individual" can purchase for their own "personal use" of automotive refinish products.  Might not matter or amount to a "hill of hubcaps", but somebody might inquire or claim they can't/don't sell to non-buinsess purchasers.

 

The "landscape" has changed, so knowing how to best traverse it can be important.

 

Keep us posted, please.

NTX5467

Edited January 23, 2016 by NTX5467 (see edit history)

[old-tank]

Ted is probably right about "say no to lacquer primer"...otherwise it might turn out to look like this .

 

 

 

[bharaway]

Great advice guys, thanks. I reviewed the eastwood site and Tetz' videos which were very informational in spite of the fact that they were also self promotional (I have no problem with that). It looks like my best bet will be an epoxy primer since I am sure the panels and parts will be stored for over a year........this is a long term and seasonal project. I will check the local paint providers for their products and compare them with the epoxy from Eastwood. My plan is to prep the metal, do the body work and do some if not all of the block sanding with primer builder. I was not aware that you could thin the epoxy and use as a sealer and that is appealing.  My understanding now is that with the epoxy primer I can later finish the body work, use the fillers, and builders on top with just scuffing the epoxy surface and after shooting the final epoxy sealant it will be ready for immediate top coats or, if too much time lapses, re-scuffing with a scotch brite pad and re-cleaning prior to the top coats. For now I do not plan on shooting the final base coats and clear coats unless I can find a spray booth locally for rent. I have a positive airflow hood, but no good or safe way to handle the environmental issues and neighborhood issues regarding filtration and correct air flow through my garage. I am thinking base coat clear coat because I hope to be putting significant miles on this baby when completed as well as showing. I read that while lacquer is truly amazing (evidenced by Old Tank's show stopper) it tends to be a bit brittle and may chip more easily for daily road use. I assume it also takes a little more TLC to maintain than clear coat. Fortunately, or maybe not depending on how one looks at it, I will likely have plenty of time to reassess the final top coat issues that I will face down the line. Thanks again for all the great input. If I find any additional information that bears sharing or may be helpful to others during this process I will give an update.   Cheers,   bob

[Mudbone]

Ted is probably right about "say no to lacquer primer"...otherwise it might turn out to look like this .

 

 

 

I can only hope!

[NTX5467]

Although the "use thinned epoxy primer as a sealer" might work per se, there are dedicated products to do that. I understand that when a sealer product is used, it effectively puts a barrier between the lower coats and the top coat to prevent later issues with "what's down there" bleeding through to the top coat.  Be that as it may.

 

Acrylic lacquer was GM's paint system of choice before the BC/CC systems came around.  It, like the similar acrylic enamel, had it's own sheen or "look" to it, just as the newer BC/CC systems look much glossier.  Lacquer was also the refinish system of choice for many body shops due to the fact it could be sanded and re-coated to remove any "trash" which might have settled on the drying paint.  Lacquer dries from the bottom up, as enamels dry from the top down.  Lacquers are more forgiving of "dirtier" spraying environments than enamels are.  NOT to forget about the issues of "atmospheric silicones"!

 

Some shops, back then, sought to shoot the acrylic lacquer "dry" (to help prevent the "dust issue" from being an issue), then trying to color sand and buff to a higher gloss, but if it was shot too dry, the paint was a little too dry when it hit the surface, and was grainy and would not buff smooth, although it did have something of a shine and color match.

 

Enjoy!

NTX5467

Edited January 24, 2016 by NTX5467 (see edit history)

[60FlatTop]

Here is a 2013 picture of a lacquer job that was done in 1981. The primer was lacquer with 8 coats of color. We used a big furnace with a grid to roll a tire and wheel onto. The car was positioned with the panel to be painted closest to the burning tire. We probably used six tires and got good short steel rims out of the firebox. I am in the process of preping the car for a repaint, hopefully this summer. I took the incorrect top off, but I plan to incorrect a few other things instead.

The paint held up very well. Still, this time I will use use a urethane primer with base coat/clear coat to minimize the mess. And I am using a gas furnace, can't burn tires in town.

Bernie

[buick man]

… Go to this site and you will learn as much about epoxy primer as you will ever need.  http://www.spiuserforum.com.  They formulate all their own proprietary systems and are more reasonably priced then the name big boys out there.  

 

I have been using Southern Polyurethane's Epoxy for about 4 years now and have nothing bad to say about it. Free shipping as well.  No iso baed hardener here.  

 

BTW: No iso's in most epoxy 2 part paints.  Iso's are found in the 2K top coat urethanes.

 

….Another real nice Epoxy/Urethane high build primer is House of Color KD 3000 series primers.  After you base epoxy prime, then apply a nice coat of this House of Color KD Primer then block.  Many colors and you can mix or blend to make the color you want. Great product.  For the past 15 years I was using House of Colors KD 2000 Series high build primers and then went to their KD 3000 primer system.  Top shelf.  They also make a great epoxy primer.  Both are non iso.

[NTX5467]

It's kind of funny (to me) how things have progressed.  When we had just acrylic lacquer (GM) or acrylic enamel (Ford, Chrysler, and others), it was possible to make either one look really good with the correct "after work".  Due to the way lacquer dries, it was usually the choice for "custom" paint and "hand-rubbed" finishes.  But in the right light, it could look hazy (due to the color sanding and such, followed by machine buffing).  Some later wax/glaze products could minimize that, though.  Still, I could tell a lacquer paint job from an acrylic enamel paint job.  EACH had their place, though.  From what I recall from back then, most shops refinished in acrylic lacquer as many only had simple spray "booth" areas, rather than the full-blown heated, down-draft booths, AND before the more intense EPA emissions regulations on such operations.

 

The shops that did use acrylic enamel for all of their work generally had to have "cleaner" spray areas, which when used correctly, also allowed them to increase production of the shop as a result.  No "hardener" was used, just straight acrylic enamel.  Personally, I liked the harder shine of the acrylic enamel.  Once, we had a painter who did an all-over repaint of a '75 Ford LTD in the factory silver metallic.  He shot it one afternoon and it was in clean-up the next day.  It looked a little better than normal.  He used the (then relatively unknown) hardener, let it dry in the heated booth over-night, then got on it with a machine buffer, and it looked great.  Although it probably needed a little more cure time.  This was several years BEFORE the base coat/clear coat OEM era.  He, obviously, knew how to make the paint system work well.

 

Then came DuPont IMRON, the polyurethane iso-____ paint that required "breathing apparatus suits" to shoot.  The first "wet look" paint, with limited colors.  It's main application was on UPS trucks, back then.

 

At this point in time, many have become so used to seeing bc/cc paint that it has become the "new normal" or sorts for the general public, even if it's incorrect for the vintage of the vehicle.  It does require a cleaner spray area, but such areas can also benefit the prior refinish systems, too.

 

As I recall, a main reason for the bc/cc paint systems was the lesser use of the base color coats.  Getting enough general coverage for a good color vibrancy, then using the clear (with UV inhibitors), for the "shine coat" and protection of the base color from abrasion.  End result, less "material" on the vehicle for less emissions and such.  Also, look on the inner surfaces of doors, deck lids, and hoods and you'll the base color in a slightly rougher texture . . . where the base color was "cut-in" as a part of the initial color painting, but the clear coat was generally "misted" as it wasn't an outer "shine" surface for the clear coat.

 

On primers, I noticed the term "high build" primer being used.  It probably should read "high build primer so there's enough to block sand for the ultimately smooooth "straight" body work for an outstanding paint job."  I believe these hb primers are also a little more porous to make them easy to sand, possibly, than normal "thin build" primers. 

 

And this gets to the total "build thickness" of the refinish system (complete from the "bare metal" on upward, including any prior paint/primer on the vehicle).  There ARE tolerances of just how thick the total repaint system's components, when fully dried, can be for the best longevity of the surface paint.  I suspect there are some illustrations of "build thickness" issues online, just as many refinish literature has similar illustrations of "paint problems" in them.

 

Spray on . . .

NTX5467