Turning Brake Drums

Discussion in 'Tires / Brakes / Bearings / Axles' started by generok, Nov 19, 2021.

  1. generok

    generok Well-Known Member Gold Supporting Member

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    Since it is -8F this morning, you sit and drink coffee and ponder your Spring Maintenance things...

    I don't know if my drums will need it, but if anyone has had RV drums turned, do you also face the magnet rotor? If so, can a standard brake drum lathe do that, or do you need to take the drums to an RV place with a special lathe? Maybe the magnet rotor never needs to be faced at all. The last time I took mine off, the face was pretty good, so maybe it's not something that happens much???

    Pondering.

    8LugBrakeDrum-Bottom-BTP.JPG
     
  2. Anthony Hitchings

    Anthony Hitchings Well-Known Member Silver Supporting Member

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    "back in the day" we used to turn brake drums instead of buying new ones - but you should also grind the brake shoes to the new arc.
     
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  3. Sjm9911

    Sjm9911 Well-Known Member

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    I dont know of anyone , at least here in nj , that turn break drums anymore. They just buy new ones, faster. I remember doing it in autoshop as a kid. But i dought anyone does it anymore. How bad are they? There isnt much pressure in them, and on both my campers they didnt need more then a mild sanding for rust. The magnets they replace. Or i would try a mild sanding on them if there not groved or worn down compleatly. I had to get all new stuff on the TT because they did not make the smaller ones that were on my camper anymore. So no parts to fix what I had.
     
  4. tombiasi

    tombiasi Well-Known Member

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    Labor costs would probably be more than a new drum.
     
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  5. generok

    generok Well-Known Member Gold Supporting Member

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    We have quite a few places that will turn rotors and drums... I can even do it myself at the Auto Hobby Shop on base. I guess my real concern is the magnet rotor face. I doubt it gets too beat up, but without a specialty lathe, I don't know how I could face that surface.

    I lost the material off a shoe this year, and I just changed out the brake plate and put it back on. The drum didn't look bad at all, so I just put it back on and away I went. That's a lot of iron to just pitch though. I can turn the drum. I guess I won't worry about what I can't do anything about on the magnet rotor face.
     
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  6. Snow

    Snow Well-Known Member

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    Last time I had drums turned
    I saved a whole $12 each over buying new ones... it really isn't worth it, as I had to drive to the shop and wait 30 minutes to get them done..
     
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  7. tenttrailer

    tenttrailer Art & Joyce - Columbus, O

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    When you replace the shoes. most people just buy new backing plates with shoes and magnets and springs. I upgrade and buy the backing plate assembly with that is a self adjuster. No more adjusting every 2Kmiles.

    Now the question is the drum. Do you replace them, or have the two surfaces trued, or clean and burnish the surface for better break-in. I re-use the drums if the groves are not bad. I burnish the surfaces. At first you will need a little more boost because of the groves, but the shoes and magnets will break in and you will need to turn down the gain.
     
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  8. tombiasi

    tombiasi Well-Known Member

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    I wish I could get 7 inch brakes with self adjusters. Do you know of any place. etrailer doesn't have them
     
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  9. ezakoske

    ezakoske Active Member

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  10. tombiasi

    tombiasi Well-Known Member

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  11. J Starsky

    J Starsky Well-Known Member

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    Take it into your machine shop or Orielly Boys autoguessory. My local Napa or O'reilly could turn them for $8 bucks.

    Most newer units don't have enough 'mills of material to take out a ridge. They'll measure it out for you.
     
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  12. Rusty2192

    Rusty2192 Well-Known Member

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    I had my drums turned at the local O’Reilly and they work great now. I think it was something like $20 a piece. I just found the documentation from Dexter online with the minimum thickness and took that to the store so they could verify there was enough material. I doubt they did anything to the magnet face, but that wasn’t what my issue was so I didn’t even look into it.

    Mine were out of round from the factory and long story short by the time I realized it was an issue I was out of warranty. Turning them was definitely cheaper than buying new ones and it guaranteed I’d have a perfectly round surface.
     
  13. Anthony Hitchings

    Anthony Hitchings Well-Known Member Silver Supporting Member

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    there is not enough room for the extra parts and their required movement in a 7" setup.
     

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