Hey guys I have a 51 shoebox that has alot off surface rust and I would like to know the best and fastes way of taking it all off. If
Ok smart ass sand paper what grit so I don't scratch the metal on the car? If I would have known what to used exactly, I would have ask the question. And before I ask the question I did search and I dindnt find anything
I used 40 grit on a da to get off all of the paint and surface rust on all my projects. 80 grit would work good if you do not have a lot of layers of paint to strip off
80 grit and a da will do the job. also, it depends on the severity and location of the rust. you can use scrapers, scotch brite pads, wire brushes, etc. eastwood also has rust converter which can help under some circumstances.
Got a better way to do it. I strip allot of hoods for louvering, both paint and rust. I have tried every method ever conceived for this over the years but I alway come back to one - 3M coating removal discs. They take paint and rust off of any surface instantly, leaving a nice conditioned surface for primer. I use these on a 4 1/2" grinder, and trigger to control speed. They require a hook and loop type pad that 3M dealers sell, but 2 10.00 pads should do your whole car surprisingly quick. If you want to know more about these in the morning I'll walk out to the shop and get some part numbers for you. The deck lid I stripped in these photos took about 25 minutes start to finish.
Got a better way to do it. I strip allot of hoods for louvering, both paint and rust. I have tried every method ever conceived for this over the years but I alway come back to one - 3M coating removal discs. They take paint and rust off of any surface instantly, leaving a nice conditioned surface for primer. I use these on a 4 1/2" grinder, and trigger to control speed. They require a hook and loop type pad that 3M dealers sell, but 2 10.00 pads should do your whole car surprisingly quick. If you want to know more about these in the morning I'll walk out to the shop and get some part numbers for you. The deck lid I stripped in these photos took about 25 minutes start to finish. Man that would be great. That was the info that I was looking for a great tip fro Some one whose try everything and has it down patten
I have also used the 3m "cheeseburgers" I use a makita 5000 sander with the hook and loop set up. Done a few cars with that set up. Love it.
http://3mcollision.com/products/abr...onditioning-disc-4-1-2-inch-coarse-14101.html these work well...might be a bit coarse, but there are a few different grits
I have used muriatic acid 50/50 with water. Put the acid in the water, not vice versa, eye protection and spray bottle. Flush with plenty of water, blow it off and spray primer or oil to keep down flash rust here in FL.
Hey guys! Sorry I didn't get to this thread to post those numbers today. I just remembered an old 3M book here in the house, so here they are. The discs I use are #3005-9020 get a couple or three of these. The backing I use is #3005-0978. These agressively remove paint, rust, bondo, what have you, but they don't take metal. They leave a nice tooth for primer to stick to as well. Make sure that you remove or mask any trim you want to save 'cause these will not destroy it, but it will mar it. I intended to do a tech write up on this, but it's a bit simplistic for a full tech. Try it, you'll love it.
Phosphoric acid and the 3M discs worked a treat for me. Phosphoric acid is the main ingredient in rust convertors, just get the one with the highest percentage. Wipe it on with a cloth and wait for it to turn white and use the discs to sand clean.
I'm working with the same issue. Any problems putting epoxy primer over phosphoric acid treated metal?
There was a thread on here a while back that talked all about the magical properties of dryer sheets and how (among other things) that they would reverse the oxidizing process so well that the part numbers and original packaging would reappear on otherwise junk parts..... But I don't remember all of the details.
I believe its etching primer that has issues with phosphoric acid. I picked some up from Home Depot following a HAMBrs recommendation and it works great.
I have seen hundreds of cars being built here on the hamb and other places.. People welding new parts onto rusty bodies... do you never glass bead your cars, down south...??? I and most guys I know, strip the car down and then glass bead it.. the whole car is like brand new.. door jams, rusty floors,top and bottom, inside everywhere... epoxy prime and you are ready to go... seems a lot faster and gives you a perfectly clean car to start your weld repairs on..??.. that is if you are doing a full resto on the body..my 2 cents for the day
I've used discs like that before, the big ones work great. Just watch out that you don't stay in they same place too long or you can build up heat, same as anything use that you'd use with and orbital sander or grinder. Do you know the approximate grit or tooth that this particular disc has? DA's and random orbitals work great too, and leave a great finished surface, but they take longer in my experience. If you have anything deeper than surface rust, like minor pitting, then you'll probably want to use some kind of chemical or acid treatment just to be safe.
I don't know the grit level that these discs have. I have asked my rep about it on several occasions but never got an answer. They are aggressive though. I do second your caution with holding these in one place too long as they will build heat pretty quickly. In my original post on this thread I mentioned "triggering" your angle grinder to keep speed down a bit as you use these. I do move them very gingerly over the surface as I work and have found that I can strip one layer of paint at a time using this method. As to the gent above who asked about bead blasting sheet metal, I second your enthusiasm for that with one exception... Your body man, or more importantly your louver guy will use all sorts of names for you that can't be repeted here while working your project! Glass beading and sandblasting while cleaning the metal beautifully has the effect of work hardening the material to the point that it becomes hard to hammer or punch with. I can see a huge difference in a louver punched in a normalized piece of 18 ga. and one punched in a blasted piece of 18 ga. Also, down here a lot of cars don't have to come completely apart to do the stripping, because down in my neck of the woods, rust repair is not usually a major issue... Just food for thought.
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