I picked up at an auction a Monarch Model A - (lot 261 No 9) its a 14 by 32 with quick change gear box, cone pulley spindle. Sleeve bearings, etc.
The challenge is whether its a 'keeper' or a scrapper.. The spindle run out at the face of the 9 inch three jaw chuck exceeds .010". Once I got the chuck unscrewed (lots of penetrating oil and a large bar, thank god no hammers needed) and put a wide point on my dial indicator, I am reading .005" runout on the threads at the front end of the spindle. Is that a valid way to test? With a 1/8 to 1/4 inch wide flat tip on an indicator?
If I grab the spindle and attempt to move it, it feels solid.
When the 9 inch chuck is running the back of it honestly wobbles back and forth. Is it possible that someone bent the spindle?
I've read about guys turning their own Jarno centers for the spindle and getting the runout down to essentially Zero.
Can I re-true the chuck backing plate to salvage this machine?
Does a thread on chuck ALWAYS reseat itself in the same place, or do I have to mark it and seat the chuck the same each time? (Sorry my Chinese 7x lathe's chucks use the crazy 3 - bolt on system)
Do I need to take the spindle completely out and check it?
My current level of experience is that I have a Chinese Sieg 7x lathe that I use for machine and equipment repairs. I've had to make replacement shafts for a couple of my antique snowblowers and the like.
The last time I touched a real gear head lathe was in college.. I worked in the inspection shack for a 'screw machine' company in Chicago.. Before that in High school shop class, 35 years ago, we each made a tapered punch in the school metal lathe and knurled the handle..
I do have .001 and .0001 dial indicators, the .0001 is not the Finger 'TDI' type its an OLD Federal plunger - dial type.
Any and all suggestions on how to proceed are welcome.. I'm not so attached to it that I wouldn't be willing to part it out for the right $$.
The challenge is whether its a 'keeper' or a scrapper.. The spindle run out at the face of the 9 inch three jaw chuck exceeds .010". Once I got the chuck unscrewed (lots of penetrating oil and a large bar, thank god no hammers needed) and put a wide point on my dial indicator, I am reading .005" runout on the threads at the front end of the spindle. Is that a valid way to test? With a 1/8 to 1/4 inch wide flat tip on an indicator?
If I grab the spindle and attempt to move it, it feels solid.
When the 9 inch chuck is running the back of it honestly wobbles back and forth. Is it possible that someone bent the spindle?
I've read about guys turning their own Jarno centers for the spindle and getting the runout down to essentially Zero.
Can I re-true the chuck backing plate to salvage this machine?
Does a thread on chuck ALWAYS reseat itself in the same place, or do I have to mark it and seat the chuck the same each time? (Sorry my Chinese 7x lathe's chucks use the crazy 3 - bolt on system)
Do I need to take the spindle completely out and check it?
My current level of experience is that I have a Chinese Sieg 7x lathe that I use for machine and equipment repairs. I've had to make replacement shafts for a couple of my antique snowblowers and the like.
The last time I touched a real gear head lathe was in college.. I worked in the inspection shack for a 'screw machine' company in Chicago.. Before that in High school shop class, 35 years ago, we each made a tapered punch in the school metal lathe and knurled the handle..
I do have .001 and .0001 dial indicators, the .0001 is not the Finger 'TDI' type its an OLD Federal plunger - dial type.
Any and all suggestions on how to proceed are welcome.. I'm not so attached to it that I wouldn't be willing to part it out for the right $$.