# cement mixer pulley repair/ replacement?



## pybyr (Oct 21, 2009)

I recently acquired a sturdy older portable cement mixer at $0.00 and it will be handy for some future projects.  

The major portions are largely intact and in OK shape, but the drive pulley for the mix barrel (rotates the barrel by way of some bevel gearing) is broken; it's about 10 inch outside diameter, with 4 arms of cast iron or steel to the center hub, and the arms are all broken off near the hub.

Am I likely to be able to get anywhere via welding or brazing?  I have done both before, and while I don't presently have equipment of my own, I do have access to/ use of the following options: oxy-acetylene, mig, and AC arc gear.  

Suggestions on technique (or links to places suggesting the same) are appreciated-- as are informed suggestions as to whether this may be a fools errand and whether I should just try to find a new pulley- in which case, sources for non-expensive iron V-belt pulleys are welcomed.

Thanks


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## LLigetfa (Oct 21, 2009)

If you are going to try welding it, do short spot weld "stitches" using stainless rod and peen it hard with a chipping hammer to relieve the stress.  If you're worried about how strong it will turn out, you could cut two round discs out of thin plate steel and sandwich the pulley between them.


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## pybyr (Oct 22, 2009)

LLigetfa said:
			
		

> If you are going to try welding it, do short spot weld "stitches" using stainless rod and peen it hard with a chipping hammer to relieve the stress.  If you're worried about how strong it will turn out, you could cut two round discs out of thin plate steel and sandwich the pulley between them.



Thanks for the suggestions.  

I like the sandwich idea, and after you mentioned it, it suddenly occurred to me that it might be possible to effect a repair without the headaches of welding castings using some form of very strong adhesive, with either discs on both sides or maybe poured as one monolithic mass in a "form" made out of something like a piece of Tupperware.

Hearth.com and its inhabitants always give me great ideas; if only budget and time could expand as fast as the ideas...


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## Gooserider (Oct 23, 2009)

My gut reaction is that you would probably be better off in the long run to just get a new pulley, I doubt that it would be that expensive from someplace like Graingers or McMaster-Carr.  Just out of curiosity, I checked McM-C, and they had 10" v-belt pulleys for $23.21 w/ several shaft diameters to choose from, the picture even looks like your description.  It would probably cost that much for most of the stuff you'd need to do a repair, not to mention the time it takes.  

I'd also be worried about trying to do a repair, both for the strength, and also the difficulty of getting all the dimensions just right - you'd need to have it just about perfectly centered and in the right plane, etc...  I figure for that kind of small money, it isn't worth the time to even mess with the broken part.

Gooserider


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## JustWood (Oct 23, 2009)

Most any electrical supply shop or motor shop should carry or be able to order what you are looking for.


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## Gooserider (Oct 23, 2009)

unknowingLEE said:
			
		

> Most any electrical supply shop or motor shop should carry or be able to order what you are looking for.



True, but possibly at a much higher price...  I figure McMaster-Carr has just about everything, and at reasonable prices - and will ship anywhere...  Kind of a one stop pointer, figure out what you need, find it on McM, and either order it from them or go to a local source, say I want one of "these" and know what to expect for a cost...

Gooserider


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## Beanscoot (Nov 12, 2009)

If you buy a replacement pulley (aka sheave) make sure to get a cast iron one, not a zinc or aluminum one.  Cast iron is much stronger and the others are not practical for heavy duty use such as a cement mixer.

Browning (USA) and Maska (Canada) are good brands of industrial sheaves.


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## semipro (Nov 13, 2009)

LLigetfa said:
			
		

> If you are going to try welding it, do short spot weld "stitches" using stainless rod and peen it hard with a chipping hammer to relieve the stress.  If you're worried about how strong it will turn out, you could cut two round discs out of thin plate steel and sandwich the pulley between them.



I 2nd, 3rd, whatever the "buy a new pulley" idea.  Cast iron is tough to weld.  If you do try to weld, preheat it to about 500 degrees in your oven before welding as LLigetfa describes.


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## Beanscoot (Nov 14, 2009)

I never thought about a stamped steel replacement, that should be okay too.  

A good reason to weld up the old broken part is to practice cast iron welding, ha ha.


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