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boygenius
May 9th 2004, 19:14
Do I really need an expensive spray gun or can I use a cheap spray gun. The local autoparts store has a HVLP gun for around $100. All I plan on using it for is spraying the body with primer before it gets painted.

E-boyz67
May 10th 2004, 01:02
Yes you can just make sure that it has the proper fluid tip for the primer you are using to get the proper film build. For instance PPG k36primer calls for a 1.4-1.6. But when spraying paint and clear better get a good quality gun because it atomizes both the paint and clear a lot better. To find out what tip,just ask the paint store where you buy the primer from they will know.

boygenius
May 10th 2004, 11:48
Thanks for the reply. I ordered some self etching primer from www.eastwood.com but there isn't any tip size instructions on the can. I will e-mail them to see what they recommend. :D

There are some nasty chemicals in etching primer, :eek: I just read the warning label.

NO_H2O
May 10th 2004, 16:08
Yep. If it works good..... it is bad for you.

boygenius
May 10th 2004, 16:19
Yep. If it works good..... it is bad for you.


So true for so many things. :rolleyes:

E-boyz67
May 10th 2004, 23:11
Aloha BoyG what brand of are you using?

boygenius
May 10th 2004, 23:34
Eastwood brand self etching primer.

jrinlv
May 11th 2004, 14:39
Not to talk you out of your choice, there are a few trains of thought on this topic, but are you planning on wet sanding at all Boyg, tons of problems can show up if you plan on using self etching and wet sanding! Let me know, JR

boygenius
May 11th 2004, 18:43
I was just going to use it as a first coat to help the building primer stick to the car. I will wetsand the rest of the primer coats.

E-boyz67
May 12th 2004, 00:07
Say bg just one note,make sure that etch prime is compatible with what ever paint system that you're planing on spraying or you'll have all sorts of problems. Also when you say primer remember that there are difference between a primer and a primer surfacer and primer sealer. Etching primer and primer sealer are not to be sanded,its meant to be used as a wet on wet system. A primer surfacer is meant to be sanded then topcoated. So if you plan on spraying the etching primer and a surfacer over that like I said make sure its compatible. Hope this helps.

boygenius
May 12th 2004, 00:15
Hmmm, this is getting complicated. Maybe I should get a "how to paint" book. Anybody have any suggestions. :confused: The last thing I want to do is use incompatable primer/paints and ruin a few hundred hours of work and thousands of dollars.

jrinlv
May 12th 2004, 01:29
I didn't mean to open a can of worms, but if you are wet sanding and break through to the self etching it will soak up the water like a sponge, and that means a high chance of rust starting under your new paint, if you are careful I guess it could be OK but it's still chancing it. Let me know if you have any questions, I'm by no means a pro but I have picked a few brains in the past..JR

boygenius
May 12th 2004, 01:44
If the self etching primer is so hard to work with, do I really need it. Will regular primer work for me. Most of the rusty/pitted panels on my car will get eastwood rust encapsulater or POR-15, so I'm not worried about getting the primer to stick there.

E-boyz67
May 12th 2004, 03:18
There are two ways you can do a paint job from bare metal.

1st- once the paint and bondo is removed either by midea or sandblasting down to bare metal you can go straight into the booth. Do not use any wax an grease cleaner or metal conditioners and make sure that no one touches the bare metal. The reason is because the metal has pours and any acids and other chemicals will not be able to come off the bare metal and when you shoot an epoxy primer on the whole car it will be traped and start to rust all over again. Just blow off all the dust and apply the epoxy primer. Then do all the repairs needed and reapply that same epoxy just before the primer surfacer then paint.

2nd-if you sand all the paint and bondo down to bare metal then you must clean/condition the metal with a metal cleaner and conditioner and apply an epoxy on the bare metal and then the primer surfacer for maximum corrosion protection. Or after sanding clean the metal with a wax and grease remover and apply an etch primer and the primer surfacer.

But the fastest way is the first way and the less work if you got the money to spend on the booth and blasting. I use PPG and Sikkens on a daily basis and both are great products.PPG makes an epoxy primer called Dp and you can apply bondo after one hour. If you're looking for quality and cost then I recommened PPG,But if cost is of no problem then by all means go with Sikkens thats my favorite.