The drive assembly to my cement mixer has finally given up. Unfortunately
neither I or the previous owner ever used the Zerk fitting to lubricate the
drive. The drive is a 3/4 inch shaft with a 3" gear on one end and an 18"
pulley on the other. Am going to have to machine a new shaft and housing.
Housing will be welded to the frame, as is the existing housing.
This link is a picture of the shaft-gear assembly.
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This link is a close-up of the gear. It is pressed on. My plan is to press
out the old shaft, or, bore it out if I have to.
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This is a picture of the shaft sitting loosely in the housing. The housing
is simply welded to the vertical channel. The larger diameter (rusty area,
middle of the photo) sits in a bolt-on cradle (not shown).
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My plan is as follows:
Remove old shaft from gear.
Make new shaft and mill a flat on one end to lock on pulley.
Make a suitable housing with 3/4"± bore.
After completion slide a short sleeve (2"± outside diameter) onto housing so
I can mount in cradle.
Weld entire assembly back into place.
Questions:
If I can not press out the old shaft, how do I center a 9-tooth gear in the
lathe. I have both 3 and 4 jaw chucks.
Don't have a boring bar 6" long. Can this somehow be done from both ends
and still end up with a concentric bore?
How do I modify the shaft so that it can take grease? Do I file a
continuous spiral? Do I do it to the sleeve? New shaft will have a new
Zerk fitting.
Keep in mind the following. Have 13" lathe and a large mill. This is a
very low rpm assembly and does not require very much torque. Even with drum
full of 200 lbs ± of concrete, you can rotate it quite easily by hand. Drum
IS NOT supported by this mechanism. It is simply a drive.
Thanks for any and all advice.
Ivan Vegvary