TR6 TR6 wheel blasting/painting

[ichthos]

I am in the middle of sand blasting my wheels. They were rusty, and the various paint jobs over the years didn't look too great either. I use a very fine blast media, so it takes me a while to get them clean. I don'tknow what the parts are called, but there are two parts to the stock wheels - the rim on the outside, and the center portion. My problem is where the two meet as you face the wheel. No matter how hard I try, I can't seem to get this hairline area clean. I don't want to use phosphoric acid because I do not want any residue, and the directions say not to use it on sand blasted parts. I had thought of using a dropper with HCl in this area, and blasting this area one more time. Has anybody else run into this problem, and what did they do about it? I will be using powder coating to paint these, so my options are limited. Any suggestions would be greatly appreciated.
Kevin

 

[TR6oldtimer]

I can't seem to get this hairline area clean. I don't want to use phosphoric acid because I do not want any residue, and the directions say not to use it on sand blasted parts. I had thought of using a dropper with HCl in this area, and blasting this area one more time. Has anybody else run into this problem, and what did they do about it?
Kevin

I have used phosphoric acid on sand blasted parts. The only problem is when you go to wipe it off, the pitted surface retains some of the acid. Muriatic acid (HCL) is actually harder to get off then phosphoric acid, and if you do use it, you must neutralize it with soda water and rinse well with water and with compressed air blow dry (you should do the same with the phosphoric acid).

These areas are hard to get right, I have seen many professionally powder coated wheels bleed through after a short time. I am not sure how I will tackle the problem when the time comes, so I will be looking to your experience as an aid.

 

[ichthos]

I know what you mean about professionals - I like learning to do things myself, and many times I do a better job. At least I trully know what has been done also. The major problem I find is it seems to take me ten times as long as a professional to complete the job. The problem with the wheel painting is that I will not know if I am successful until some time passes. Kind of a bummer since it will literally take me a couple days to do this. I am going to try and get sandpaper in this area, blast it again, and then apply some phosphoric acid with a small paint brush. I will just repeat this process until I am happy with the results. I am hoping that when I preheat the wheels that any any liguid or residue will burn off. I guess the protective layer of the phosphate is better than the rust. I also thought of applying a thin line of seam sealer to this area to seal it after I am done. I'll be watching to see if there are any other responses.

 

[DNK]

Kevin- If I remember right yours is a 69. Didn't they use a different wheel in that year?

 

[sp53]

Hi Kevin I do a lot of blasting with 70 grit sand and I find that 125psi at about, I think, 10 cmf the paint or rust or whatever comes off the metal and actually polishes the metal and prevents the return of oxidation. Perhaps you need to turn up your compressor a little. You will not hurt a wheel.

 

[ichthos]

I think you are corect, Don. I later years had more or less vent holes if I remember correctly. SP53, thanks for your input. I have a Cambell Housfeld 5 horse, 60 gallon tank compressor. I do have it running at 125 PSI, and it delivers 11.4 CFM. I can't remember what grit I am using. I do have some problems with moisture. I am running a hose 40 feet which doesn't help matters. There is just those four areas the size of a crack that the sand will not seem to penetrate. Have you ever blasted the wheels before?

 

[sp53]

I have never blasted any tr6 wheels, but I have blasted more things than I want to remember. What do you mean by a forty foot hose? Do you mean from the hopper or from the tank. In addition, new sand will make some difference for the better because the old sand has tendency to smooth out and powder after many uses. Your compressor has plenty of push to get in there and knock that stuff out too, so I do not know. Try some new 70 grit sand 110 to 125 psi and just set the tip right on the crack and go; it will not hurt a wheel. If you get too close for too long on sheet metal you can warp it. I would stay away from the acid treatment they are only a Band-Aid. They basically superficially complete the last electron on the atomic structure of the iron element, so that the atom is complete and quits excepting oxygen. The acid wears off like paint. I do not know if your wheels are made of iron or what, but it sounds like an iron alloy. Iron oxidizes/rusts red, aluminum white, silver black, copper green ect ect. Alloys like stainless steel have the element chromium mix in so the alloy is sealed on the last atomic band of the alloy and does not oxidize. If I remember right, the alloy would need four electrons in the last band that circle the proton in order not to be oxygen hungry. You could have some wheels made out of gold and they would work because the last band has four electrons naturally.