cast iron drums ??
 

is there any way to know what replacement cast drums I have who and when they were made? PLASMA, GROSS.,? CANT FIND ANY MARKINGS, they look to be fairly new, never turned, thanks.:) around .25+- undersize .250-260 wall thickness..real nice castings.

Re: cast iron drums ??
 

Maybe try calling Mr. Gross and/or a few Model A parts suppliers .... maybe they can assist ..... worth a try.

Maybe unknown to some, but, most manufactured bells when rung have a distinct musical note, like the musical key of A or whatever.

The Randy Gross drums may ring with a different musical note than that of the Plasma drums ...... also, drum notes will change when metal is removed after the drum is turned.

FWIW: If all (4) drums are turned, it is not necessary to get them tuned up. LOL

Re: cast iron drums ??
 

A couple of pictures might help.

Charlie Stephens

Re: cast iron drums ??
 

Just curious, does it matter, quality wise? Is one better than the other?

Re: cast iron drums ??
 

Here is a Plasmeter drum. Excellent quality.

Re: cast iron drums ??
 

On the topic of brake drums but a little off the thread, does anybody still swage the wheel studs in? I've never done it and can't see why anyone would.

Re: cast iron drums ??
 

Synchro: And what do you do??
Paul in CT

Re: cast iron drums ??
 

The late Mr. Mel Gross told me he saw many swage wheel stud disasters come into his cast iron drum business ...... after 20 years of Model A Forum Messages and reading about all of the Model A engine re-building disasters ..... why would drums be different?

Re: cast iron drums ??
 

I tack weld the back of the stud to the flange on the hub and (only for good measure), I drill through the brake drum between a couple of the stud holes and put a countersunk set screw into the flange. Inspection of the brakes involves ONLY the removal of the wheel, one set screw and the drum which always goes back on in the same position. No need to remove the hub - especially pleasing on the rear ones. Cars have been done this way for many decades, some with no set screw at all. Swaging is a PITA and causes lots of problems when the "squished" material of the stud "oozes" between the drum and flange as often happens. I think this was one of the things Mel Gross was referring to when he made the statement mentioned above.
The studs we buy these days have a longer plain shank than they used to, I suspect to allow for the thicker cast drums. It is best to remove some metal from the shoulder before using them this way or on steel drums.
This might open a can of worms but it has worked for me and I suggest it as an improvement for all Model Aers. It can't be seen when the wheel is on so no probs with judging either

Re: cast iron drums ??
 

Synchro, have you found a particular stud that has a better radius to maintain a better centered fit?

Re: cast iron drums ??
 

Amen to that!

The process of installing new studs is truly a lost art. If it is not done correctly and with the proper tooling and support fixtures on a 20 ton press the probability of inflicting damage to both the drum and the hub is very high.

This is especially true when installing new cast iron drums. The lug is like a rivet and it must swaged (crushed) properly so that it does not put any pressure on the drum otherwise the drum will crack around the holes.

Care must be taken when removing the old drum so as not to warp the flange on the hub. A cutting tool in generally used to cut away the shoulder on the lug created during the swaging process before it is pressed out using a correct holding fixture.

It is also important to use correct new studs. The length and diameter are critical. And there are various sizes out there.

My advice to anyone contemplating purchasing new cast iron drums is to contact Randy Gross. He has the drums, the correct studs The correct tooling and fixtures, and a lifetime of knowledge about Model A brakes and the swaging process. His prices are reasonable and he is a nice fellow to do business with.

Randy is located in Southern California. Cell 714-292-8660

Tom Endy

Re: cast iron drums ??
 

Randy Gross is a good man to deal with. I am sure he can help you.

Re: cast iron drums ??
 

The studs don't hold the drum centred - the centre boss does. Not sure what you mean by stud radius.
It would be interesting to get Randy Goss's thoughts on this one but I don't think he posts here any more.

Re: cast iron drums ??
 

Tom, you made the comment regarding various length hub bolts (I think you used the term studs), and I do agree with you that we find different lengths that do not match the factory print that I have. The reasoning that I assumed there was a difference is due to the extra thickness of the cast drum in the bolt area as opposed to the thickness of the stamped steel drum. Since I did not know the answer to the original poster's question, I did not say anything however I suspect the different manufacturers have a different thickness in that area, and that would be the way to differentiate between the manufacturers. I have always subscribed to the therory of using the hub bolts manufactured by the same one who is having the drums made as they are likely meant to be used together.

I am unaware anyone is manufacturing hub bolts to the factory specifications. Do you know of a repro supplier of those?

Re: cast iron drums ??