After you have cut the rust out.

[skokie]

After the rusty area has been cut away and a new piece put in, do you sand , prime and paint that one area?

Thanks

[Brainchild]

grind the welds,body filler if neccesary,sand smooth,prime,and paint.Don't leave any metal exposed You'll have the same proble begin again.

It's OK in primer for a while if you're painting the whole truck

[bobs409]

It's a good idea to use weld thru primer on the bare metal before you weld it in. Once all the welding and grinding is done, I spray an etch primer, then treat the rest the same as regular body work.

[skokie]

Thanks for the tips. My plan so far is this.
1. Identify area that needs cutting.
2 cut out what needs to be cut.
3. rust more that area and let it sit until it cures.
4. spray weld through primer on the area and let it cure.
5. weld in the pieces.
5. grind the welds down.
6. primer and paint the area
7. seal the area.

Did I miss anything?

Thanks

[grayw0lf]

Weld through primer? I did not know there was such thing...? It doesn't contaminate the weld?

What brands? Where to find? etc.

[skokie]

I dont remember the brand name. Its at the house. I can look and post back later tonight.

[arkracing]

3M and SEM make it in spray bombs...but it is kinda pricy $20 for the 3M

Most paint makers have it..just go to a parts supplier that carries paint of you local paint provider

[72CSTC5]

The original purpose of weld through primer was intended for when two panels are overlapped and welded together and plug welded such as replacing a quarter panel on a vehicle. You are not acutually supposed to weld over weld through primer. It contaminates your weld. You will have a lot of pop and splatter. It should only be applied in between your weld areas. It wouldn't hurt however, if you could butt weld in a patch panel and then spray the welded area from the back side after cleaning the area of course. Then undercoating as needed. This is straight from a 3M rep himself in a training course for my bodymen. I manage a Chevrolet Dealership's collision center.

[wolfthing2000]

I have various opinions, but a lot of people prefer an epoxy primer before any fillers as then there is no chance of moisture getting behind the filler.
For what it's worth,
Dave

[skokie]

Is there a specific epoxy primer that I can use? I dont have a spray gun. Is there a rattle can version that I can use that will hold me over until I get the cab media blasted and painted?
Thanks

[wolfthing2000]

Depending on where it is at I would just get a 30.00 quart of epoxy based primer and mix some and brush it on. You will use a sandable filler primer over the top anyway. And if it is under carpet or floormats it won't matter. That is what I am about to do with my 69.........
Dave

[skokie]

Ok im a little lost. So do you put the epoxy primer on first then put the sandable primer on and then paint? Sorry I dont do body work.

THanks

[wolfthing2000]

Epoxy primer or etch primer first. ,, then the sandable filler stuff ( soft and easy to work) to establish a smooth finish for the top coat. I have another post going for a long time question of when to do the Bondo filler for haeavy scratches and dents that can't be worked out with conventional body hammers.
Dave