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dale farley
05-25-2010, 06:04 PM
I've looked at the "Articles" section and see nothing about removing small dings and polishing the stainless. Is there a written procedure anywhere for this problem? I watched Harry do it in South Dakota, but I have forgotten the details. I caught my front panel on my driveway again a couple months ago and need to do some straightening and polishing. This is a stainless panel that hides my hydraulic pistons for the front bumper. I have beat it out the best I can, but now I need to clean it up by sanding and polishing.

I just bought some 50, 100, 220, 400, and 600 sandpaper. My plan is to do a rough sand job with my 7" grinder/sander then use a jitterbug with the finer papers; but I am not sure this will get the job done, and I am not at all sure how I'll polish it once I finish with the 600 sandpaper. Harry made it look fairly simple, but it is a little more complicated when you don't know what you are doing! After taking the pictures, I realize I still have some more hammering to do also.

Also, is there a way to delete a thread that you start. I tried to, but don't see any way to do that. I know I used to do it?
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Jon Wehrenberg
05-25-2010, 07:34 PM
Dale,

The dents you show are such that the metal has stretched. Trying to get them flat will require that you use a heavy steel block on both sides so as to not create a new set of distortions. It is an art unless you have access to a heavy press and can exert the necessary pressure to flattent the dents and the sheet metal as much as possible.

If the steel blocks are protected with paper or masking tape it will help prevent the rusting of the stainless due to the transfer of iron particles to the stainless. Stainless steel will rust and continue to rust if you transfer iron particles to its surface.

Try to get the dents as flat as possible because the next step is to sand the stainless until the distortion caused by the dents and their removal has been "erased". Think of it as removing material such as sanding wood or bondo. If the metal is thin it needs to be as flat as possible to begin, and you need to be careful of heat build up. Take your time.

Once the dents have been sanded out work using progressively finer grits. 50 is likely too agressive unless you have very heavy metal. 100 may also be but you can practice on scrap steel to see. I have used a small belt sander with good success because it is easier to keep the surface flat. Disc sanders or grinders are very hard to use to keep the surface flat especially when using the coarser grits. Take your time.

I work up through 320, 400 and eventually get to 1000 and then 1500. When I am satisfied with the results of sanding I then use my high speed buff and white rouge. You will likely want to sand the entire part using the 1000 and the 1500 and buff the entire part. The laser cut logo may present a problem, not so much on sanding but if the buff gets caught and tries to "grab" the part. You will need to be very careful around the laser cut portion. Take your time.

There is not much you can do to mess up except for two things. On thinnner material you need to get the dents and dings almost perfectly flat because you run the risk of sanding through the metal if you are trying to sand out deep dents or dings. The second thing you need to be very careful of is heat. On heavier metals you run less risk of distortion, but on lighter materials heat will make the part twist and distort. That is why I am stressing take your time. If you can get the dents rough sanded and they are gone, the remaining steps are just time consuming but in the end that expenditure of time will pay dividends.

With flat blocks of steel and a big hammer you can get that part looking pretty flat, but there is no substitute for finding a shop with a 100+ton press brake and dies to coin the metal. That alone will save you a considerable amount of time and make the end result look like new with minimal polishing and sanding. The key is the tonnage a press brake can impose on the part will literally push the metal back into its original shape to a great extent and greatly minimize the amount of material you need to remove to make it flat and shiny.

dale farley
05-25-2010, 08:35 PM
Jon, Thanks for the info. I will see if I can find a local shop with a press. I didn't even know they made 1000 or 1500 sandpaper. I also didn't know I could induce rust into the stainless. The closest thing I had to a heavy steel block was a 4 x 4. I laid the stainless on it, placed a piece of steel plate on top and hit it with a big hammer. Believe it or not, it looks a lot better now than before I started, but it still has a long way to go.

Where do I get 1500 sandpaper and white rouge? This would be much easier if I just got the guard off Jim Keller's bus!

Jon Wehrenberg
05-26-2010, 06:34 AM
You have my permission to steal the guard off Jim's bus. But if you cannot get through the high security fencing you can probably buy finer grit sandpaper at any shop that sells to collision repair shops. I think I got mine at a big NAPA store. They go as fine as 3600 which is what you would use as a final prior to buffing on Plexiglass or CC shields. (Not kidding about that)

I have bought polishing buffs and white rouge on-line and at truck stops. I use the stick form of rouge but it is also available as a liquid. It is what you would use to polish your wheels unless you intend to take Jim's highly polished wheels along with the guard. When Harry did the demo in Santa Fe he used a big buff but you should consider a smaller less agressive one. I use 6" un-sewn cotton buffs because they generate less heat and put on a finer finish with less marks. You will be covered in short pieces of thread using those buffs but they do a nice job.

JIM KELLER
05-26-2010, 06:47 AM
I enjoyed this thread and I just welded my guard to my shocks for safe keeping. I am pondering a fail safe method of " wheel retention."

JIM CHALOUPKA
05-26-2010, 06:56 AM
Dale, don't bother with the repair, just leave the trim piece off :D or replace it with some flexible black mud flap material, didn't you say you have bent that piece before :p


JIM:) :p

truk4u
05-26-2010, 08:02 AM
Now that's priceless, a Liberty owner telling a CC owner to just replace the stainless piece with a mud flap!:p

dale farley
05-26-2010, 08:36 AM
Jon, Thanks for the information.

Tom, I agree with you. I can't take Jim C.'s advice. The only way I could take his advice, is if I paint "Liberty" on the rubber flap.

Jim C., You are also right. I have bent the piece before, but I am hoping that I won't do it again.

Jim K., You are entirely wrong. The Bible says "prefer your brother". Just give me your stainless shield and wheels, and I won't have to steal them.

Jon Wehrenberg
05-26-2010, 09:21 AM
I'll bet Jim K can fix you up with sources for all of the materials you need Dale. He may not let you steal his parts, but his body shop can probably tell you where to get the abrasives, buffs, rouge, etc.

JIM KELLER
05-26-2010, 01:09 PM
Dale, I'm laughing so hard the tears are running down my cheeks !