I might be able to find this with a "search" but PRIMER yields a few too many results. I'm about to have my pickup bed sandblasted and the old timer is GOOD. He won't ruin the sheet metal. My question. Is there a primer I can lay on the pickup bed's bare metal... with an old style gun... outside... if the dirt isn't blowing... that will protect the metal and will make a base for a little body filler and a future paint job? Something that won't have to come off later except through the body work done to it. Keep in mind this is west Texas and we had some humidity back during disco. But not alot. I'll get a water trap for my compressor too. Thanks, Dan
Hey Dan, I'd do as much straighting of the bed sheet metal, at least roughing- out of the metal, prior to the sand blasting, also any welding. If you are going to have this sand blasted, be sure that you're re- ady to shoot the primer THAT day. Over freshly blasted steel I would't think self-etching primer would be warranted. A good rule to follow, when picking primers and sealers, is to always consider what the top coat will be. HOK and some of the other big money kustom colours ,don't advocate using anything other than their primers for compatability reasons. Cheap primers and sealers arn't always cheap in the long run! Swankey Devils C.C.
Ditto...and I wouldn't do anything without putting on PPG's DP 40/DP50 FIRST... primer won't stick to bare metal for very long...if you don't put down something for it to stick to...(a chain is only as strong as its weakest link!). I used DP50 on some chrome bumpers 10 years ago, then used NCP250 primer, then paint over that...it was a real bitch getting the DP off when I wanted the chrome back..and the chrome was still in great shape. R-
I would first clean the metal. Use the spray gun to spray the cleaner on with a lil more PSI, say 40-50. That way you're working with clean metal before you etch it. Cause alot of times the material used is recycled and also they can be pits (realy realy realy small) I've used PCL, good for your money. Also 5 star is realy good though you may need to thin it out a lil. good luck! Ken
I'm planning on getting my frame sandblasted in a couple of weeks as well. Do i have to weld the motor mounts, tranny mount, and all the other stuff i need to weld before i take it to get sandblasted? Because i was just planning on getting it sandblasted first then weld the mounts i need, so i wont have to bother grinding the rust of before i weld.
I've been told by several bodymen that do quality work that's the only way it should be done (bondo/bodywork over DP50)...and the last three jobs I've done have been that way...of course, there are pros and cons (and opinions) to every 'system'...listen to advice, pick one and use the one that works for you. R-
Not necessary to do it before...as long as you get it clean enuff for paint afer you weld, and you're the judge of that. I just did a '55 Caddy frame that way...hated to look at the dirty, greasy, road grime covered frame as I was working on it...so had it blasted before building motor/tranny mounts and running break lines, gas lines, etc... R-
I would get all of my mounts fabbed, holes drilled and any other work that involves cutting, drilling and welding BEFORE I'd sandblast. This way you will not have any raw steel sittin around the shop, startin to rust again, wile you're doing that fab work. Too, the sandblasting will remove any fire scale and flux left over from welding, neither of which ya wanna paint over. If you're thinkin-well if I sandblast, than weld, I'll be welding on clean metal, true but sound welds , even if stick welded, must first be ground well below any scale, rust, grease or paint. This way a coat of primer covers all the steel at the same time, with no adhesion problems. Swankey Devils C.C.
evercoat makes a good polyester filler called feathercoat that fills and primes in one shot if you dont have that bad of body dameage?? also it is great when blocking real smooth!! and is water proof
I use House of Kolor Epoxy almost exclusivley. Sand the blasted metal first, removes any sand stuck in the pores of the metal, and smoothes it a bit. You can bondo over, or under it, it sticks extremely well, seals , and even FILLS. 5 coats will fill 36 grit scratches (not that you'd want to do it that way). Also, it sands pretty good, better than most epoxies, probably not as good as a urethane, though. You can paint pretty much any paint over it, any brand, any formulation, lacquer to urethane.
DP(LF) 40-50 etc are NOT what they used to be 20 to 30 years ago (LF means lead free--they did NOT used to have that suffix.) They don't have the same ingredients or corrosion protection or film build they once had. If you are an epoxy believer, do some searching for a higher solids primer that will give a better bare metal corrosion protection base. They are out there. Even PPG has some "better" epoxy primers. Read some tech info available on PPG's site. They have some very good epoxies in their industrial and aircraft lines. DP primers-4.6lbs. per gal solids---EDP and EFP epoxy primers over 12 lbs per gallon solids. I'm in favor of self etching primer on sandblasted (rusty-pitted) old car bodies. (I always run a DA sander over the sandblasted steel with 180# to 120# and then solvent clean before priming.) If you read the tech info on most epoxies, they will say to use metal conditioner/acid etch on rusty steel before application. It's messy and time consuming, but the proper way to prepare steel for priming. Etch primer, properly applied, will usually convert the rust in the sandblasting pits without metal conditioner ( the acid is in the primer). I don't think etch primer gets 100% of the rust nuetralized, but epoxy primer nuetralizes 0% rust. Metal conditioner should NOT be followed with self etching primers, in most cases. Always read the tech info (NOT JUST THE LABEL DIRECTIONS) for the proper application procedures and compatible topcoats. Most steel automotive panels are acid treated and phosphate coated when new. The 2 step metal conditioner/ phosphate coating has been used from back in the 1920's to today. If you ever stripped an original Model A Ford panel (original paint) you will see a goldish tint to the metal. That is the factory phosphate coating. Of course most of the Model A's we see are rusty and pitted at best, with no original metal treatment intact. An intact phosphate coating is an excellent foundation for most primers. Self etching primers are a very good "shortcut" to replace the phosphate coating protection after sandblasting instead of the time consuming and messy metal treatment process. A good quality self etching primer followed by a good quality 2 part high build (urethane) primer is an excellent foundation for most topcoats. A good quality epoxy followed by a compatible 2 part high build is also an excellent foundation for most topcoats. Always study and read up on the products and procedures for application for these systems before starting the job. overspray
This is the absolute truth listen to this man and your paint will stay forever, always sand sandblasted metal before priming I use 180 on a DA pain but an old PPG rep taught me well over 30 years ago how to make paint stick, now if I could just figure out rubber bumpers!
THANKS! for all the replies. So my plan is finish welding the last few holes. Pretty much already straightened the majority of the dents. Get the bed blasted. Hit it with a DA and 180 grit. Wash it down with solvent. Question... any certain solvent or just laquer thinner? Then self etching primer. Thin coats or fairly heavy? and can I use my syphon gun? This is for a '63 Ford styleside "shop truck" and I plan on some kind of bedliner. Shouldn't I still primer the inside of the bed but maybe the sanding isn't necessary? Still fuzzy on the body filler. Where I need it ( like where I filled the stake pockets ), shouldn't I grind the self etching primer back off to bare metal? Dan
Tinbender is correct and, from reading his posts on the HAMB, he is obviously a skilled and knowledgeable craftsman. http://www.jalopyjournal.com/forum/showthread.php?t=8318&&showall=1 This is a long read and you really need to check some tech sheets and read some more before starting the project. Depending on what brands of products you are familiar with or have available to you in your area, you need to research a system to meet your needs. I'll be gone for a couple of days, but I trust the HAMB will help steer you in the right direction. overspray
Aw shucks! Thanks OS! glad you pointed out that you need to sand blasted metal. I was going to respond to this post, but man I get tired of going over the same stuff over and over
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