Turning brake drums

getting them mounted true is the only challenge. Surprised a toolroom lathe would be large enough to even consider it.

-jsw

That old South Bend document covers about everything. You will probably need to make some cones or adapters to mount it. You do need to find something to add mass to dampen vibrations, or it will ring like a bell the whole time, and the cut will be wavy. Once it starts getting wavy it is almost impossible to correct. You need a heavy boring bar. The Ammco toolholder is 1.125 hex. Ideally it would be mounted directly to the cross slide after removing the compound. Drums sometimes develop hard spots from localized heating. These can be very hard to cut out, as the bit skips over them. The solution used to be to use a grinder attachment. Modern carbide may be sufficient, I don't know. It's dirty work. I'd rig up a shop vac hose on the boring bar.

The lathe will swing 12" and the brake drum is only 10".

I was thinking about useing a 5C fixture collet turned to the diameter of the center hole on the drum. Seems that would simplify centering and squaring.

Best Regards Tom.

Thanks for the link. Some great stuff in that pamphlet, saved that one for reference.

Best Regards Tom.

The most common problem is vibration. They "sing" like crazy.

Old-time solutions include cutting big "rubber bands" from old inner tubes, and stretching a few of them around the drum, until the singing stops. You can arrange other things to dampen it.

I turned the drums on two of my little cars, an MG Midget and a Ford Fiesta. Fortunately, I no longer have drums. Unfortunately, discs are too big for my SB 10L. However, I could turn the discs on my old Fiestas, which is an indication of why they were scary to drive on a race track.

Generally speaking today if they need turning you are better to replace them. They are on the thin side to start with, so machining them at all makes them too thin to work properly. Drums are (generally speaking) pretty cheap. Not like you are in the middle of a third world country with an obsolete vehicle (like my old '49 VW in Zambia in '73 or '74, where I had to hack-saw and chisel a 1961 VW drum (half an inch too wide) to fit when the spline stripped out of the original on a trip)

This is true for newer vehicles, maybe 1990 on. But earlier vehicles had more meat on the drums. New rotors are much worse, built to be replaced rather than turned from the get-go. I'm not looking forward to financing the replacement of my rear disc+drum rotors on the Tundra down the line, lemme tell ya. The emergency brake uses a drum made in the interior of the rotor hub. Very odd setup.

That said, I have 54k miles on the beastie now and need to look at those.

Sounds like that was a real joy to perform. Ugh!

You do a lot of strange things when there is no other alternative. That drum took almost 2 hours of hack-sawing and chipping to get it to fit - on a Sunday afternoon about half way between Choma (the new capital of southern province) and Macha (home of the Macha Research Trust and Malaria Institute).

I also made an "exhaust system" for it out of copper plumbing fittings, Land Rover driveshaft, and a gas filler.

Had a Peugeot 204 and the engine mount let go - making it impossible to shift gears (4 on the tree) so I welded up a solid mount to stay mobile until I could get a new rubber one shipped in. It was involved in a rather major colission - T-boned a Datsun 1200 and shortend the car 4 inches and swayed the front end almost 10 inches - would never have even THOUGHT about repairing it here - I pulled and hammered it back into shape without replacing a single part other than the battery. The battery in the VW died - and it was over a month's wages for a new battery. I jury rigged a Land Rover crank and crank-nut to the end of the crankshaft and hand cranked it for months until the battery in the big Leland Lorry died - one bad cell, second from the negative end. I hacksawed off the neg post, drilled it and screwed it to the intercell link in the middle of the battery, pulled ou the back seat, and threw it in.

We had a land rover that put a rod through the block. We bored it out, machined down a fergusson tractor sleeve and shrink-fit it in - then finish bored it to fit the original piston. With a cube of rad-sealer it sealed up perfectly

Among a lot of other crazy things.

Lovely.

Now _that_ is an odd combination.

I'll bet she was a doglegging bitch after that. I saw a truck with no rubber in the eye of a leaf once, and he had about 1 foot of dogleg. 'Twas a wrecking yard parts retreiver truck; no big deal.

Not safe, but runnable, eh?

Heh heh heh.

Those are some heavy duty repairs. No parts but a full machine shop? You were lucky.

I helped a lady with her Buick or some odd GM veHICKle one time. She was in the parking lot at the grocery store and I was coming home from work wrenching, so I was still stinky. Several people were standing around, trying to help, so I put my bags of groceries in the car and walked over. Her shifter was loose, with no feeling of detents. I put it in park, crawled under the car with my trusty Mac4, and fixed it for her. The shift linkage had come loose from the auto trans lever on the tranny, and the interlock was moved by said lever, so nothing happened when she tried to start it. I think that was the first time in public I'd heard applause for a quick fix. I was probably still a deep shade of maroon when I got in my car and left.

Mac4 = MAC 4" crescent wrench which had been ground to rotate farther open until it could handle a 9/16" nut or bolt. I've had her for over

40 years now. VERY handy in so many tight places.

The Chinese are now outsourcing to Ethiopia, too? I knew they were already outsourcing to India, Vietnam, and Thailand. Small world.

It was apparently an old WW2 Kubelwagen engine - 985CC FMCV1 and 10 taxable HP - NO parts available to replace the (at that time) 25 year old. There were not supposed to be any in civilian production, but the muffler from the 1100 and 1200 cc engines wouldn't fit - and even they were virtually unavailable.

The vehicle was registered in Zambia as a 1949, but may well have been produced earlier than that. The fact that it originally had 4.5X16 tires would indicate production before 1946 - and the FMCV1 would indicate 1943 or earlier ---as the 1100 cc engine came out in early

1944. It also had a magnesium trans case - 1949 had Elektron Alloy, and it had no cable bonnet release - also a 1949 innovation., and the brake drums were modified in 1948 ---

Mine had the old brake drums, the 4X16 rims, no internal hood/bonnet release, Magnesium cased "crash box" transmission,FMCV1 985cc engine,

- all signs of pre-1949 production - and actually pointing towards

1946 mechanicals - - - - - But it had the wolfsburg crest on the bonnet and the 1949 style speedometer - so who knows what it REALLY was - and it could have been parts of several vehicles by the time I got it with who knows how many owners before me - the last being a south-african "coloured" VW mechanic.

"Who am I - and if so, how many?"