Sandblasting Wheel Rims

[Kameron M]

Hello. I'm having my body panels blasted with an aluminum blast media, and primed in heavy duty epoxy. I was going to have my wheel rims given the same treatment at that time as well. One question on that, however: how should the inside of the wheels be treated: i.e. is it safe to blast the inside splines of the rim? Is it safe to paint the same?

[Marv]

First of all Kam, I would strongly try to talk you out of using an aggressive media like aluminum blast, black magic or similar grit like material. Aggressive media will disrupt the surface of the metal and tend to warp body panels. Would also shy away from using it on wheels as well.

The more acceptable methods for sheetmetal is a.) baking soda (messy but effective), b.) plastic media, c.) walnut shells, and d.) glass micro bead. These will work on the wheels as well. Shouldn't be a problem in and around the spokes although it won't remove any rust that may be up in the nipples. A good spray solvent wash afterwards is adequate to remove most media residual. Plus a check for loose spokes and true running rims.

There is a warning to head that your items may tend to flash rust quickly if they don't get back to your paint/body shop in a timely manner.

I'm having my scuttle and toe board sheet metal blasted right so we can fill in holes that the previous owner put there for his "improvements". My shop is using walnut shells. Then they will go off to the body shop to fill the holes and be primed in epoxy primer as well.

My media blast/powder coating shop says there are other newer methods out there now too as blasting media but I'm not aware of their benefits or pitfalls and not every shop will have the processes in place. They are "wet" crushed glass and dry ice blasting. Any media blast method will have shortcomings and benefits, so investigate and choose wisely grasshopper!

Marv
TC5141

[Kameron M]

I am having a very well-regarded sandblasting shop take care of me. I will talk to them about the concerns you bring up about the aggressiveness of the aluminum material, though from what they told me about over the phone it seemed like it was the most effective material for chewing off the surface rust and old paint layers.

I have nothing to worry about flash rusting wise: the sandblasting shop goes straight from blasting to priming, practically in one go. They do a fair number of car resto's this way and so far they haven't had any issues. I will be sure to talk to them about the warping concern though: for the MG I know is made out of far thinner material than american counterparts of the same vintage.

The process I have been encouraged towards by a few resto people and the sandblasting shop I have spoken to is to have the body panels blasted and primed as they are, then to lightly sand and tackle spots in need of repair with fiberglass. One of my friends in cleveland has a good hand for doing fiberglass patchwork, and for price and longevity he says it is the way to go.

What I am more concerned about is the rudge wheel splines. For sure, the bead and spokes of the rim can be blasted safely, but what about the splines?

-kam-

[Duncan M]

Kam-
If you are having the bare rims (no spokes) blasted and painted, one concern I could think of is getting the spokes and nipples through the holes. Could be a tight fit with enough paint added on, or could cause chip's.
Marv has a point about aggressive media on the body panels, but I can only say I did sand blast on the wheels after I had freed up the spoke threads and made all truing and run out adjustments, etc., with thread dressing on each spoke/nipple thread. Then I painted the wheels on the same day to prevent any rust. The epoxy paint is very good for bare metal.

[Marv]

Kam:

Unless the spines have been exposed to a wet/damp environment, why do you want to blast them? If they are rusty then do a low pressure blast with the proper material sparingly. Maybe your shop uses aluminum grit on sheet metal but I haven't heard of many that do. Like yours is the first!

Duncan's point on the wheels is one that is well accepted in wire wheel circles. Any motorcycle shop will tell you that they disassemble and have the hubs, rims, and spokes (if not being replaced) all blasted independent of assembly.

Marv
TC5141

[Duncan M]

Kam-
I missed that. Leave the splines alone. Maybe a few swipes with a soft wire brush before your put on a light coat of anti seize (splines) and install on the car. Are you pretty sure the splines on wheel hubs and axle hubs are OK?

[Marv]

Kam: just a side note, I can take sheet metal such as is on our TC's and blast a hole right through it with my shop machine using aluminum oxide grit.
Marv

[Steve Simmons]

I would protect the splines while blasting and clean them afterward by hand. You don't want to remove material, nor have abrasives embedded in the metal, grinding away on the hubs as you drive. Best of course is to disassemble the wheel and then rebuild with new spokes, but blasting in one piece works also. You may just get a bit more cracking and rust around the spoke nipples after some miles have been put on.

Do yourself a favor and repair the rusty metal areas properly. Fiberglass is not the way to go. I have a bunch in my '39 that has to be torn out and done right because someone went cheap and it didn't last. Nor did it look very good. Considering how much money it costs to paint, it's nice to know that the underlying material is as good as it can be.

[Kameron M]

I have a set of seven rims for the car and hand-selected the best (truest) four at a very helpful old school shop today, with the aid of their balancing machine. The spokes are all in good order and the wheels are reasonably true (three of these I purchased from dry storage of a collector at $125 a pop). They have a very very light surface rust on the splines, but no flaking, pitting, or deep penetration is evident.

The places in the body which need repairs are few and far between. One place I think I will have to do a fiberglass patch on is the inner fender, for it has a large spot that has been swiss-cheesed to the point where very little can be done save buying a new panel or patching over it. For the most part, the body panels are straight and without dents, but could use to be cleaned up and primed. The only ding I can think of is on that louvered piece that covers the frame rails in the front.

But long story short, I have a long while to figure out exactly what to do with each dent once I am mostly primed up and the rust is taken care of. On the subject of the wheels, I will ask them not to shoot the insides of the hubs with primer as to not gunk up things, and I will clean the splines out myself with a wire brushing.

Given what all of you have mentioned about the aluminum media, I will be absolutely certain to ask the sandblasting shop about that worry of eating right through the steel. Given their exxeptionally good reputation in this area though, it seems to me like they have things sorted out and won't just eat through my car and say 'here you go, all nicely chowdered up for you'.

[Marv]

My comments Kam, were not meant to imply that simply shooting aluminum oxide media at the skin of a TC is going to eat "right" through it. It would take some time with the gun in concentrating on a small area to do so on good steel, less on the swiss-cheesed stuff. I was simply exemplifying that aluminum oxide media is more than less universally accepted as being more aggressive than desired for thin sheet contoured steel. But hey, if the price is right and you have confidence in these guys plus have seen their results on other projects, go for it! That's the beauty of this forum, you are not required to act on the advice any of us offer, - simply by asking the question.
Good Luck.
Marv
TC5141

[Kameron M]

No no, I think it is a worthwhile and legitimate concern though. The shop I am going to does have a very good reputation for doing exactly this. If you are curious, they are Newbury Sandblasting out of Newbury Ohio. From what I have heard from other people in and around cleveland they are about the beat when it comes to blasting anything in this area.
I will be sure to talk to them when I drop the parts of though I suspect that they will just be careful about it.

Everyone has different experiences with these sort of things. I don't mind your thoughts at all, or anyone else's.

[stephen stierman]

Fiberglass is NOT a proper repair, nothing more than a band aid no matter what you are told. If you have rust holes in metal they need to be repaired by welding in new metal or making up new panels, which in many cases is not that difficult on a TC. What about the timbers under that rusted metal? If the metal is rusted out, the timbers are not going to be any better.

[Kameron M]

I have a new set of timbers. The place most in need of the repair is right on the side of the panel where it is largely obscured from view but seemed to have attracted a good splashing of rocks and water over the years. It seemed to me that it would be a good candidate for such a repair.

[stephen stierman]

Picture?
Pull it off and bring it on down to me and I will weld it up for you if it can be done, I am not that far away.

[Kameron M]

https://drive.google.com/open?id=0B09pd ... 2hnYUY4VGc
This is the biggest ding.

This is the rusty spot
https://drive.google.com/open?id=0B09pd ... m9KMDZJS3c

This is the rest of the folder.
https://drive.google.com/open?id=0B09pd ... nd3WmZNSGM

[stephen stierman]

Easy enough to cut out and weld a small section in. What about that passenger side door lower rear section under the hinges, is that a rust hole? The front apron should be easy to reshape with a bit of hammer and dolly work.

[Kameron M]

I'm fairly certain there are no holes in the doors.

[stephen stierman]

Take a close look, from the photo, it appears to be a hole with maybe bondo in it, but maybe not. I could weld that stuff up for you, if I had it.

[Steve Simmons]

I'd take him up on an offer like that, and it's a pretty long drive for me.

[Kameron M]

I think that is just the lighting.