Drub brake specs for turning 12" drums?

[darkone]

Hey all, was really hoping to get my drums turned today, but the guy at the shop said they were too far gone.... thing is, les schwab said they were right on the edge. Bothing with this truck, as far as buyying parts goes, has been easy or accurate. So im turning to you guys (The professionals) to tell me what the min spec should be on the drum to turn it. I can't afford new drums and would just assume throw on discs if I had to replace the drums, but as I said my budget wont allow that. Anyway, any help would be appreciated.... I already have new shoes and hardware so I guess im going to put that together this afternoon. Thanks in advance for any input
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[john]

I think the drums have a minimum thickness cast in them. Should be easy to find. They would be below minimun after turning if they are on the edge now.

[darkone]

I had someone else tell me that, but these havent
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[68Stepbed]

Where are you located? I have an extra set of drums I'll give you if you're close enough.

[darkone]

Washington state. Eastern wa at that
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[68Stepbed]

Originally Posted by darkone

Washington state. Eastern wa at that
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So much for that idea. You could almost buy new drums for what the shipping would cost, not to mention cleaning, painting and having them turned.

[cdowns]

drum brakes dont have pads

[darkone]

Originally Posted by cdowns

drum brakes dont have pads

i thought at you're age you'd be tired of picking posts apart

[72 GMC Longstep]

I am just going through this on my 72 c20 with a dana and 12x2.5" brakes. There was no stamping on mine either. The rule of thumb is the nominal size plus .090". So in your case the max is 12.090". Some of the drum manufacturers same only 0.060", but they are in the business of selling drums. So .090" over is safe.

I am having difficulty finding new drums as mine are completely shot (one measured 12.250" before cutting!). Mine were metal on metal.

All the suppliers I checked here could not find any in stock in Western Canada (or any brake shoes). But I did find them on Rock auto and have ordered shoes and drums, so we will see how that goes. The issue that worries me is all the parts listings show dana 60 rear end with leaf springs have 12x2.5's. They don't say anything about a Dana with coil springs (mine has coils) - it seems like mine should have a Corporate rear end with 11" brakes? I know the diff is oriiginal to my truck. Does yours have coils or leafs? Dana or Coroporate?

[GASoline71]

Had a pal that worked at a local machine shop and when my rotors or drums were "on the edge" he would just "clean them up a little" by taking off just a tad with the lathe. But that was a friend, so he had no problem doing it for me. Any body lese won't do it because of liability issues.

If they are remotely close to being out of spec (i.e. just over), a turn on the lathe will take them under legal spec for a shop to turn them. You're gonna have to bite the bullet on this one and just get new drums.

Gary

[darkone]

welp, im definitely not able to replace the drums, so i sanded the insides down, with 220, then 400 after blowing out all the rust dust etc. i rebuilt the rears with new pads and hardware also. I know my pads will be eaten alive, but it was all i could do really. opinions? safety concerns? Obviously im going to have to be careful with my braking, but they are a lot better than before that is for certain

[Murphy IRE]

Make sure if you get the 12" drums, that they are the correct ones. I found out the hard way that there is a difference. I had to have them shaved down on the back rim and then milled at a 45 to mount and freely rotate with the plate.

[fastwillie 696969]

i wont let anything go out if its on the edge or just clean it up ,heat cracks will come in as fast as you got the new shoes on ,drums start to blue then the brake fluid gets boiled and then pedal is mushy