Pre-paint prep question

[Smokeater11]

I have been removing all the old paint on my rig down to the bare metal and fixing whatever I find as I go. My question is outside of the area that have been repaired and need to be smoothed out with filler, do I need to cover all the bare metal with a thin layer of filler and block sand it or can I just spray the primer onto the bare metal and sand that. The body of my rig is in amazing shape with little to no dents over most of the large flat surfaces. The only areas I am having to do any work to at the areas right behind the tires where rock and crap have been slung up and dented the corners. Cost is an issue(isn't it always) and I'm not looking for a "show" style paintjob but I do want it to look nice and smooth. I just don't want to go through all that application and sanding if it really isn't needed. I don't mind sanding the primer but if I can cut out some of the elbow work I'm all for that. Just had elbow surgery 8 days ago. I've never done any type of paint work so if this sounds petty or stupid please forgive me. Thanks, Mark

 

[byson1]

Are you using a compressor and air gun or spray cans?

 

[twisted_mr]

bare metal needs to be painted with etching primer. you should make sure it is suitable to use with the paint you choose. I believe you paint over the etching primer with regular primer (I did) Good luck.

 

[rcmbronc]

I would epoxy prime all the bar metal. You could also epoxy the whole vehicle to seal it. Then you can spray with a good 2K high build primer and then block sand that. Then paint can be applied over the 2K. You can also spray over the epoxy as it will act as a sealer, but it does not sand real well.

 

[Smokeater11]

Are you using a compressor and air gun or spray cans?

I will be using a compressor and Binks spray gun. Most likely I am not going to be the one to shoot the actual color on the truck as my shop is just way to dirty and dusty. But I am going to try to do all the prep work I can to cut down on the cost at the paint shop. I have an aquaintance from my racing days that used to paint our racecars but he is super busy and way too expensive to have him do it all. He told me that if I would do all the prep he would cut me a real good deal.

 

[byson1]

I'm painting a Jeep (sorry) right now and I agree with the comments for epoxy primer. I'm no expert but all the informatio I have gathered recommends epoxy primer (2k) over bare metal vs. ecthing primer. Some use both but I do not think it's necessary. On the metal parts I have already sprayed with epoxy, they ahve turned out good. That stuff is tough. On top of the epoxy spray your 2k high build urethane primer. You have a short window (hour or so) after spraying the epoxy and then the urethane primer or you have to scuff or sand the epoxy so the uretahne will stick. Good luck.

 

[bronko69er]

If I had my paint job to do over again I would craft somthing to protect my fenders from rock dings. Let me explain further. Some time after my paint job I noticed little dimples on the "fins" (top section next to the hood) of my front fenders. After a few beers and pondering, I realized that when gravel gets caught in the tires, it flies up and dents the metal from the insde resulting in the little dimples I was seeing. I would reccomend a thick undercoat up in there or some type of "skirt" to keep this from happening.

 

[Tito]

BC Broncos has the skirt protector for your fenders now, check their site, they look pretty good.

 

[Smokeater11]

I am assuming that the 2k you guys are referring to means 2 coats. If I am wrong someone please enlighten me on the correct meaning.

 

[rcmbronc]

The 2K is a two parts high build primer that sands real nice to help block sanding the primer. I would recommend 2 to 3 coats and then sanding to see if it is flat enough.

 

[byson1]

I am assuming that the 2k you guys are referring to means 2 coats. If I am wrong someone please enlighten me on the correct meaning.

2k means 2 part coating. You mix them together. With urethane primer you mix the primer with the activator. The ratio's vary depending on the manufacturer but normally it's about 4 parts primer to 1 part activator. The activator acts like a catalyst to harden the primer and forms a much better bond to the surface than a 1k or 1 part primer (also known as ready to spray like in a spray can). That's why I asked what you were spraying. Since you have a compressor and sprayer you should definatley take advantage of you ability to use a 2k primer and top coat. Go here www.autobody101.com/forums/ and you'll learn more than you ever wanted to know about car painting.

 

[tsmustangs]

Here's what I do on mine.

1. Bare metal gets treated with metal prep, (acid ectch)
2. Sprayed with self etching primer
3. Then if it has had a fair amount of repair work, i.e. sand scratches and such I use PPG's K36 primmer, (K36 sands a little easier than the higher build K200 primmer) sand all of that with 320 including the areas of old paint I didn't remove, then I use PPG's LF 40 or whatever color works for your topcoat. That will protect the vehicle until you can to the final paint.
4. At which time I sand the entire rig one more time with 320 and then reshoot a coat of LF 40 followed within 30-60 minutes with my topcoat. This is a slow drawn out process and can get expensive. But I only have to do it once and the rust doesn't come back.

Terry

 

[allenfahey]

I have been removing all the old paint on my rig down to the bare metal and fixing whatever I find as I go. My question is outside of the area that have been repaired and need to be smoothed out with filler, do I need to cover all the bare metal with a thin layer of filler and block sand it or can I just spray the primer onto the bare metal and sand that. The body of my rig is in amazing shape with little to no dents over most of the large flat surfaces. The only areas I am having to do any work to at the areas right behind the tires where rock and crap have been slung up and dented the corners. Cost is an issue(isn't it always) and I'm not looking for a "show" style paintjob but I do want it to look nice and smooth. I just don't want to go through all that application and sanding if it really isn't needed. I don't mind sanding the primer but if I can cut out some of the elbow work I'm all for that. Just had elbow surgery 8 days ago. I've never done any type of paint work so if this sounds petty or stupid please forgive me. Thanks, Mark

There are 2 ways you can finish your bodywork, sand the paint off the dent with 80 and the immdiate area around the dent. Then use your filler for the dent and when you put you finishing glaze on you can go over the paint with it as long as it is sanded with at least 180. I saw a bodyman at work a few years ago do it that way and thought filler shouldn't be over the paint. I spoke to the Evercoat rep and he told us it was a good repair as long as it was the top coat going over the paint. As a painter I like it done that way better since there seems to be less blocking the primer.


2nd way....
Sand a large area around the dent with 80 then finish your bodywork in 180, feather edge all areas around it with 320, you should have a finger width around each layer. Beyond the last layer sand with 400 and a red scuff pad about 4" around that. Make sure to cover the 320 scratches with primer. If the rest of the paint work is in good shape it doesn't need to be primed. Just finish all you bodywork with 500 and the old paint too if you are doing an all over. If the current paint is in good shape you can blend it. Doing it that way
you don't need to paint the next panel as long as there is enough room to blend. If that is what you are doing then 800 and a grey scuff pad on the old paint work.