VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 Repairing 1928 brake drums

So I am looking for input. The 1928 front brake drums are not being reproduced. I have a pair with significant pitting in one area where the car sat for an extended time. Being stamped steel and not too thick I doubt they could be turned to remove pits not that turning could be done on these anyway. So the question is how could be pits be repaired to make the drums serviceable? I have thought of setting the drum in wet sand to reduce heat warpage, weld the pits and grind back to smooth but this is labour intensive and I am not sure it would work. Any other ideas?

I am thinking that you have three options. One find replacements (not an easy task to find better ones). Clean the surface and use them as is (maybe with a little sanding to round out the edges of the pits). The new linings should last a while and provide reasonable stopping. Third is the welding described. That is intriguing, challenging and maybe fatal (to the warped drums). With a MIG welder making short timed welds, the large heat sink and the tendency for the weld spots to shrink it just might work. Yes it would take a lot of time and patience but just think about the level of satisfaction. And the bonus, it would let the rest of us know whether it worked. Saving these older parts will get more critical as time goes by.

Good drums are really hard to find. Given the problem of finding the 5/32 lining for the fronts I am not keen to wear out linings quicker on pitted drums. There are three drums with hubs on E-Bay (for 28 Pontiac which is the same as 1928-29 Chev woods) but all are pitted as bad or worse then mine. Too cold now but maybe come spring I will try it. I can pack wet sand all around the drum to provide cooling and judiciously weld spots slowly one at a time. after a number are welded take it out, grind and repeat as necessary. Still open to ideas. This could be helpful to many an early Chev owner.
Thanks

Well, I'm no expert here but welding cast is mostly fruitless in the end. What about brazing the pitting and turn it on a lathe?

There is some welding rod that evidently will tig cast iron, but I've never used it. I've had best luck brazing brass to repair cast iron.

Alan

Rube Goldberg here again. ;-) Here's my hairbrain idea:

1. Turn the drums down (on a lathe) to get to a smooth surface
2. Make two sleeves that have an outside diameter .003 inch larger than the new inside diameter of the hubs (an interference fit). Make the sleeves so that a large-ish amount of material is still on the sleeves (1/4 inch thick?)
3. Put the sleeves in the freezer overnight
4. The next day, heat the hubs on a BBQ to 450 degrees or so
5. Drop the sleeves into the hubs
6. After the hubs cool off, turn the inside diameter of the sleeves (now installed in the hubs) on a lathe back to spec.

Okay everyone: ready, aim, shoot.

Dean

Dean,
When you wrote "hubs" I think you meant drums.

If you are going to put new metal on the inside of the drums then it is only necessary to get a relatively smooth surface on the inside drum surface. Don't have to remove the pits but do need to have enough metal to hold the sleeve.

Guess I didn't aim well enough so missed!

Why not find someone that can spray metal on the area with the pits? Then true the inside of the drums on a lathe.

Hi Alan,
These drums are stamped steel not cast as stated in original post so welding is not the issue. The issue here is warping a relatively thin drum out of round. Jus a reminder, I am talking about front drums as rear drums are being reproduced (for at least most models cars and light trucks).

I thought about the spray welding but am not familiar with the process. I will check it out. My first thought was to find a way to do it at home for all those who like to attempt such stuff. Eventually what ever works best will probably win out.
Thanks.

First shot. I think the drums are too thin to sleeve. If you take out enough material to have a thick enough sleeve to handle the brake heat then the drum may not have enough strength to hold up. Also I think this much work would constitute going ahead and making new drums.

At one point these stamped drums were being reproduced out of Aus. Is that source no longer in business? Seems to me the number was $160 or $180 per drum. Virtually any one I see at swap meets that is reasonable I have picked up. Just because I figured I could get a few spares out of the lot. The mistake a lot of people make is that you can not sand blast these drums. Carefully sand the high spots down.

As far bas I know only rear drums are reproduced. Fronts have a rolled lip and are not flat like the rears where they face up to the hub/spokes. I have a pair of NOS ones I picked up at flea markets for the rear. I actually have enough to put my wheels together but I have a few extras that are good but have some pits as described before. If the pits were repaired they would be really good drums as they are not scored or worn. Others may not be as fortunate to find good drums so I was thinking if I can figure a way to save them then the information would be useful to others.

I bought a new pair of the Aus made rear ones, they are wearing surprisingly quickly, I suspect the originals did as well.

Odd how the insides wear as bad as the outside, because the parking brake should only be applied at rest.

I also have a pair off my spares car that in the distant past have had the cylindrical parts turned off the centres and new ones welded on, they are now very worn again.

The amount of wear tells me that this is a perfectly safe repair as it hasn't failed in service.

I will have a go at doing the same trick again on these drums, if I can't find a steel tube the right size, I'll maybe roll steel rings, weld the ends together and then weld them onto the drum centres. Although there's a chance the cross joint may cause grabbing.

I'll make them thick enough to be turned inside and out to the correct thickness.

With luck they may even be slightly better than original as the originals where never turned to correct any warpage.

Don't see any problem with doing the same to front drums.

Cabboy, I sent you a Private Message with a lead for a pair of good used drums.

Cheers, Dean