Continuous use of a manual slack adjuster?

**katy** · Jul 15, 2021, 06:58 PM

Anyone on here ever use a manual slack adjuster for continuous operation as a speed reducer?
Just wondering how one would stand up.
Also I would like to know what the ratio is.

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**Frank S** · Jul 15, 2021, 09:49 PM

Originally Posted by katy

Anyone on here ever use a manual slack adjuster for continuous operation as a speed reducer?
Just wondering how one would stand up.
Also I would like to know what the ratio is.

They are not exactly made to be used as a speed reducer there are no bearings inside of them just bushings
If you wanted to use one as reduction gear for something like a weld positioner they work great and last quite a long time if you keep the worm and gear well greased. You can turn them with a drill motor at low RPM intermittently.
I wouldn't want to use on as a speed reducer without remanufacturing it with bearings and a proper housing.
I turned 1 into a torque multiplier once, before I bought a real one But I don't remember the ratio though

**desbromilow** · Jul 17, 2021, 06:24 AM

in one of the Australian metalwork forums, there is a guy who used one to make the gearbox of a cold cut saw...he used Holden wheel bearings for the main spindle, and set the gears in a "closed" submerged oil gearbox so they run in oil continuously. unfortunately I cannot provide a name or reference since it's been a while since I read about it.

**javelin68** · Jul 17, 2021, 03:57 PM

They work good to rotate engines on engine stand. Will rotate a diesel engine easily and hold.

**NortonDommi** · Jul 17, 2021, 06:18 PM

Learn something new every day. I have been adjusting these things for years and never given a thought to the above uses.

**clavius** · Jul 18, 2021, 05:53 AM

Originally Posted by NortonDommi

Learn something new every day. I have been adjusting these things for years and never given a thought to the above uses.

Agreed.

Having never worked on large truck air brake systems I had no idea what a manual slack adjuster was so I googled it. This is an interesting bit of info to file away, I could see it being a handy gizmo to repurpose things you might be building. They are amazingly inexpensive considering what they are.

Thanks for educating me, I learned my first new thing for today!