Cast Iron Compressor Pully

[Arbo]

My air compressor had a catastrophic tumble last week. I broke the cast iron pulley on the compressor. The other night I did a little welding. It has three fins coming from the center hub, and all three are broken. I did the preheat and postheat thing, and buried it in kitty litter over night to let it cool slowly. When I got it out, one had cracked right on the weld. I ground it out and tried again (same procedure as before), and now the next fin cracked right on the weld. I am getting good penetration (.035 flux core, high nickle content wire). I am thinking that my heat is not distributed evenly. Am I thinking right, or talking out of my butt? Maybe I will try using the gas grill to bring the temp up and down more uniformally. Any suggestions would be greatly appreciated. Sorry for the rambling post...

[Al T.]

I heard cast iron is a bear. Why not try brasing it? It won't get so hot to cause cracking.

Let us know how it turns out!

[Guest]

Re: Cast Iron Compressor Pully

Originally posted by Arbo
My air compressor had a catastrophic tumble last week. I broke the cast iron pulley on the compressor. The other night I did a little welding. It has three fins coming from the center hub, and all three are broken. I did the preheat and postheat thing, and buried it in kitty litter over night to let it cool slowly. When I got it out, one had cracked right on the weld. I ground it out and tried again (same procedure as before), and now the next fin cracked right on the weld. I am getting good penetration (.035 flux core, high nickle content wire). I am thinking that my heat is not distributed evenly. Am I thinking right, or talking out of my butt? Maybe I will try using the gas grill to bring the temp up and down more uniformally. Any suggestions would be greatly appreciated. Sorry for the rambling post...

Arbo. it may not be the procedure at all....it's sounds like you did all you could and did it right. The cast iron wheel configuration usually does what you see it doing...cracking in some other place, no matter how much you preheat and postheat. It's the shape that is giving you fits. Also pully's need to be balanced... I don't know if that is your issue, but when I get these jobs....usually I tell 'em to buy a new one.

[Arbo]

Rocky,

I used the gas grill tonight, like I was rambling about earlier. It staye together this time without breaking. The only thing I gained was the satisfaction of it not breaking though. The hub is so out of center that it wobbles at least 1/4". My next problem is finding a repalcement. Maybe you can give me some guidance there as well. The pully is 10" diameter, 1.25" thick. Not so odd so far...the hole for the shaft is 3/4 on the back and tapers to 5/8 on the outside. I was looking in the McMaster Carr and Grainger catalogs earlier, and could not find anything. Anyone with any suggestions on where to find such a creature?????????????

[Bob]

Even if this is not a Sears Craftsman, you might try looking at their compressors. Sears is pretty good about spare parts. I found an odd-ball drill press part for a non-sears unit that way.
Also web search for "air compressors", many suppliers offer repair parts.
Good luck.
Bob

[R. Nelson]

Re: Cast Iron Compressor Pully

Originally posted by Arbo
My air compressor had a catastrophic tumble last week. I broke the cast iron pulley on the compressor. The other night I did a little welding. It has three fins coming from the center hub, and all three are broken. I did the preheat and postheat thing, and buried it in kitty litter over night to let it cool slowly. When I got it out, one had cracked right on the weld. I ground it out and tried again (same procedure as before), and now the next fin cracked right on the weld. I am getting good penetration (.035 flux core, high nickle content wire). I am thinking that my heat is not distributed evenly. Am I thinking right, or talking out of my butt? Maybe I will try using the gas grill to bring the temp up and down more uniformally. Any suggestions would be greatly appreciated. Sorry for the rambling post...

Hey Arbo, a few weeks ago, managed to seperate my vise from it's base was not sure if it could be repaired, but thought I would try. I got some rods for my stick welder made by Forney called NOMACAST for cast iron, using an angle grinder, I ground a bevel on the vise where it meets the base, pre-heated it to 400 D., I have an old oven in the garage, welded it, put it back in the oven, and reduced the heat 25 D. every half hour, so far it's holding. I realize your pully is history, but next time you need to weld cast, it's food for thought.

R.Nelson

[Blkvoodoo]

any idea who made the compressor or how old it is ?
single cyl or twin ? single stage a 2 stage ?

how big ( hp, amp rating, voltage ) is the motor ?

I used to repair smaller compressors, I might could send you info on where to look

Kevin

[email protected]

[Arbo]

Well, here's an update. I don't have a name to go with the compressor. The only marking on it is "Made In The USA". I did find a pulley with a 5/8" bore. I already talked to a machine shop that does really nice work. He said that he can taper ream the new pully to match the shaft on the compressor. We'll find out for sure next week when he gets it done. I am hoping for the best, always looking for a way to save a buck.