4" grinder and these disks OK for rust/paint removal, or bad idea?

[cledford]

Are these OK to use? I tried both on the 4" angle grinder today on a junk tractor I bought to experiment with. They certainly removed rust & paint. However, since plently of sparks fly (even with light pressure and moving the disk quickly), I'm assuming some metal is being removed. It any worse, better or equal to sand blasting, which isn't an option for me?

FWIW, I had been looking a tractor restoration book recently and there was an interview with some guy famous in the field. He claims that he NEVER blasts things - especially bodywork as it causes warpage. He "sands" everything. I didn't take this to mean he *hand sands* everything and have seen on the car restoration TV shows where they used pneumatic sanders. Am I using too much or just enough with these type disks on a electric grinder?

Thanks,

-Calvin

[CMA's129]

The blue one looks like a Rolec they are used to prep bare metal before painting to remove oils and such that are left buy your hands after you give it a good rub down to find waves and dents and the such. Good body shops ware rubber gloves for everything after they use the rolec. We use the flap wheels at work for cleaning the ends of large copper pipe before soldering. Sand blasting is bad for thin sheet metal it wont hurt heavy stuff as long as you dont get it too close.
Did you get the NOS muffler for the 169, I'm shure there is a lot of fellows that would like to get there hands on that?

[Psevins]

Havent worked on tractor body work BUT have done automobile. Sandblasting will distort but I think the biggest issue is control. Its pretty easy to quickly blast a hole through your sheet metal before you know what happened. I always limited my blasting to small solid parts. Thin metals I preferred to use a chemical agent to remove paint and then proceed with griding or rust removal disks.

If the rust is bad enough your going to end up removing some metal, so it might be necessary to skim the surface once done with a body filler to achieve a smooth finish. If its just light surface rust, I'd stick to sanding my hand and then treating the area with either a nickel enriched sealer or "rust converter" (which might be the same thing, I've used both) The rust converter is an aerosol pre mix while the sealer came in quarts and goes on rather thick (makes runs very likely on vertical surfaces).

Just my experience, ask a 100 different body shops and you'll get nearly that many methods recommended.:biggrin2.gif:

[Matt G.]

I have *very carefully* sandblasted sheetmetal with good results. I'd worry a bit about removing too much metal with those. I've had good luck with electrolysis to remove paint and rust. Wire wheels are very effective for non-sheetmetal parts. An $8 can of paint stripper goes quite a ways, too.

[Mike in NC]

One thing you can use is the 3M skotch brite pads that are about 4" in diameter and the attach to a drill. They work good for paint removal, and will not take off metal. You can try a local autobody supplier.

[jbollis]

Originally Posted by Matt G.

An $8 can of paint stripper goes quite a ways, too.

Funny, I did just that today. Local car parts store also has a paint department. He sold me a $7 spray can of aircraft stripper. I have to admit,I was a Little skeptical. But after stripping all the paint of the cast iron rear in about 20 minutes,I was impressed.



JOE

[Psevins]

good stuff, just use it in a very open aired location!!

Chemical strippers are messy.

The blue disk? NO.

The flap disc you have posted is excellent for repair prep but not to remove paint for paint prep.

I sand blast areas that are difficult to sand/DA like the tail light recesses and around the foot rest area. I sand blast the aluminum nose pieces as well, some areas you just can't get to with sand paper.

If you see sparks you are removing metal.

DA all paint surfaces for paint prep. If you don't have a compressor to keep up with a DA use an electric DA, Porter Cable makes a very good one for about $55, discs are about $20 for 50 IIRC.

I'm not a body man but I'm a finish man, homebuilder and have been for about 26 years, I see everything from the finished product backward, try that way of thinking and do nothing that causes more work when you get to the end.

Learn to use your products. Someone mentioned a skimcoat of bondo...unless you are making a repair why go through all that work? Don't try to cover a mess you create, it's better not to make the mess in the first place.

Further on sand blasting, the tin on these tractors is pretty heavy, I don't know the gauge but the fender pan ain't no door skin on a cheap Chevy...it can take it so feel free.

Scott



Edit:

You guys don't to take it down 100% to bare metal, DA it out. Also learn about primers and using primer to build up, wet sand and prime again if necessary to remove minor sanding marks. Wet sand your first coat of finish and recoat finish.

[c02cutter]

Buy a cup wire brush. awesome paint remover...