02-01-2015, 09:13 AM
I'm so impressed with the progress!
The old yoke really appears to be FUBAR. How in God's name could anyone ever mangle a casting that badly? Seriously, 3 out of 3 backlash adjustment mechanisms blown right out. Unreal.
My question lies in just what do you need to do to fit the newer one to your machine? From what I can tell you have to add a lubrication port (bottom photo), but not sure what else it is that needs to be done. I can imagine that a critical factor for life of the wear parts (the bronze nuts) would be assuring the center line distances from the mounting surfaces to the centers of the screws/nuts is the same. It doesn't appear that the original was "scraped in", so were there any shims in the assembly? When you say you need to drill and ream locating holes, what is off so much that the better one is not "plug & play" in your machine?
I can't speak to spindle bearing break-in from any point of authority. If it were me I would simply run it at say 500 rpm for a couple of hours in each direction, let it cool, then bump up to 1500, and so on. Watching for excessive heat would be crucial. If it gets too hot (as in, can't keep your hand on it), there may be an alignment issue, but I sincerely doubt you'd have assembled it in any haphazard way.
BTW, is the head otherwise fully operational? Got feeds on the quill and is it running up & down in it's housing smoothly?
The old yoke really appears to be FUBAR. How in God's name could anyone ever mangle a casting that badly? Seriously, 3 out of 3 backlash adjustment mechanisms blown right out. Unreal.
My question lies in just what do you need to do to fit the newer one to your machine? From what I can tell you have to add a lubrication port (bottom photo), but not sure what else it is that needs to be done. I can imagine that a critical factor for life of the wear parts (the bronze nuts) would be assuring the center line distances from the mounting surfaces to the centers of the screws/nuts is the same. It doesn't appear that the original was "scraped in", so were there any shims in the assembly? When you say you need to drill and ream locating holes, what is off so much that the better one is not "plug & play" in your machine?
I can't speak to spindle bearing break-in from any point of authority. If it were me I would simply run it at say 500 rpm for a couple of hours in each direction, let it cool, then bump up to 1500, and so on. Watching for excessive heat would be crucial. If it gets too hot (as in, can't keep your hand on it), there may be an alignment issue, but I sincerely doubt you'd have assembled it in any haphazard way.
BTW, is the head otherwise fully operational? Got feeds on the quill and is it running up & down in it's housing smoothly?