The Stovebolt Site Forums The Shop Area Paint and Body Shop surface rust removal

Last night I pulled out my 4 1/2 inch grinder and a flap sanding disc. I tried this on an old door. It worked well to knock off the rust. I primered it with rattle can primer, then rattle can paint. Looked good with a few swirls.

I am wondering if the swirls can be taken out with another process? Sanding disc with fine (120) sand paper? Hand sanding? Board sanding?

Any experience or advice?

TIA

Oh. This is a surface grinder which has the shield.

I am not sure if taking off the metal shield will allow me to sand flat. Or if this would be too dangerous.

Thanks again.

If you get too flat, you can really do some swirls. The jitterbug will take out the swirls, but it takes a lot of time and patience. It is best to not get the swirls in the first place.

As for taking the shield off, I took mine off the first day and don't even know where it is now. I haven't hurt myself yet.

no you don't need the guard, use some good glasses or a face shield ... angle grinders and flap discs don't work well really flat, although the flap can gouge easily at too much angle, and they're most useful for initial stripping, not finish work .... you need a DA sander after the flap, using progressively finer paper to at least 300something before initial primer, then using that primer as a 'guide coat', finer sanding before more primer and paint

if you don't have a DA [or air] use a quarter sheet palm sander - lots of sanding, finer and finer, is the key to getting rid of the work marks

Bill

Thanks Bill. I was trying to keep from buying the DA sander. I will have to put it in the budget.

Forgive my ignorance but DA sander?

DA sander, sometimes called a random orbital sander ...moves 2 directions at once, sorta

Bill

Crap. I worked on the back of the cab and there are a lot of bullet dents in it. Looks like a pellet gun or bow-n-arrow. I am hoping that reaching through the window and using a hammer-dolly set will work. Or look at Woody's site will help.

Lots of work ahead.

I've used a wire wheel on my angle grinder to remove paint and rust on the entire truck. The wire wheel is really aggressive with the twisted sections of very stiff wires on it. No scratches! I've also used the cup style wire wheel as well. The only time I used a flap disc or sand paper on my angle grinder is to grind down welds.

Hi Ron. Thanks for the info. I assume the wire wheel is the pig-tailed type that is flat?

Torch, hammer, dolly, and blasts of compressed air.

You need to shrink the metal. If you try just hammering them out you will wind up with stretched metal and an oil-can condition.

Here's the drill.

You on the inside with a torch and hammer.
A friend on the outside with a dolly.
Heat dent until cherry red.
Dolly on metal.
Tap the edges of the red spot around like a clock face finishing off with some taps in the center.
Blast with compressed air.
See magic happen.

It might take you a couple to get the hang of it but once you do you'll wish you had more to do... it's actually fun.

Correct!

Doug, DA (Dual Action) can be used as a full rotary or as an oscillator.
DG

Update.

I have been banging around on the lower back portion of this 48 cab every night. I have found the dents not so bad. Thanks for all the information and advice. I am a person to gather as much info as I can before starting. This probably annoys some folks.

What I have found is the side and center support beams have the skin bent around them. It would be nice to have a wide flat metal bar (like a slap hammer?) that I could put between the support beam and the skin. I may be able to straighten the skin out.

Any thoughts or experience in this?

Thanks again for all your help

On Saturday I tackled the roof. Using my 4 1/2 grinder I used everything that fit. I tried the wire-pig wheel, grinding wheel, and sanding disk. A lot of work and wore me out. But it looked good with lots of minor pits. I sprayed some rust converter after I cleaned the metal.

I pray the rust does not show up again while I am alive.

Rust requires moisture and oxygen to grow. Rob it of either and it will remain dormant. Sounds like you're good to go.

Hi Woody. What filler did you use on the outside, in the front side of the cab, where there was lead?

TIA

Evercoat Everglass to rough it in and Rage Gold to finish.