USNmechanic
Aluminum
- Joined
- Dec 1, 2016
After trying to sell my 10K for several weeks with no serious offers, I decided it probably wasn't selling for what I though it is worth because it was mounted on a couple sheets of plywood on a floor dolly and it still had years of grime on it. I built a bench out of 2 1/2" x 3" hardwood boards I've had stickered up in my basement for years, and used a 1 1/2" thick pine top that I got from a guy at work. I finished cleaning and reassembling it this weekend, and have decided to keep it .
Before:
This Morning:
I checked the spindle bearing clearance this morning, and found the front bearing has 0.002" clearance and the rear has 0.005". When assembling the headstock, I made sure that the bearing retainer screws were loose and used a torque wrench to tighten the bearing cap bolts to 10 ft lbs based on the rebuild manual's recommendation of using approximately 20 lbs of force and a 6 inch wrench. I then tightened the retainer bolts using just my thumb and forefinger on a stubby flathead screwdriver. The bearings and spindle journals looked flawless when I cleaned them, and the indicator I used is older and not as responsive as I would like, especially in my unheated shop. So reading that too much clearance is better than too little, I decided to run the lathe for an hour at maximum spindle speed and check how the bearings heat up. I used an infrared thermometer to check each bearing temperature every 5 minutes, and below are the results.
Does anyone have any experience with how much temperature rise should be expected? Since the temperature rise was almost 35 deg F over the hour on the (tighter) front bearing, I'm nervous to remove any shims, especially from the front bearing. The mass of the headstock is pretty large, and I would assume that a lot of the heat being generated is being wicked away from the bearing and not showing up as an increase in temperature. I definitely don't want to go chasing the spec only to mess something up, especially if I'm not confident in the clearance measurements to begin with. I also didn't notice any significant drop in oil level in either oiler, and the surface finish on the aluminum collars I turned to align the tailstock was excellent.
Any advice would be greatly appreciated as I have no idea if the temperature rise I saw was normal. Thank you!
-Keith
Before:
This Morning:
I checked the spindle bearing clearance this morning, and found the front bearing has 0.002" clearance and the rear has 0.005". When assembling the headstock, I made sure that the bearing retainer screws were loose and used a torque wrench to tighten the bearing cap bolts to 10 ft lbs based on the rebuild manual's recommendation of using approximately 20 lbs of force and a 6 inch wrench. I then tightened the retainer bolts using just my thumb and forefinger on a stubby flathead screwdriver. The bearings and spindle journals looked flawless when I cleaned them, and the indicator I used is older and not as responsive as I would like, especially in my unheated shop. So reading that too much clearance is better than too little, I decided to run the lathe for an hour at maximum spindle speed and check how the bearings heat up. I used an infrared thermometer to check each bearing temperature every 5 minutes, and below are the results.
Does anyone have any experience with how much temperature rise should be expected? Since the temperature rise was almost 35 deg F over the hour on the (tighter) front bearing, I'm nervous to remove any shims, especially from the front bearing. The mass of the headstock is pretty large, and I would assume that a lot of the heat being generated is being wicked away from the bearing and not showing up as an increase in temperature. I definitely don't want to go chasing the spec only to mess something up, especially if I'm not confident in the clearance measurements to begin with. I also didn't notice any significant drop in oil level in either oiler, and the surface finish on the aluminum collars I turned to align the tailstock was excellent.
Any advice would be greatly appreciated as I have no idea if the temperature rise I saw was normal. Thank you!
-Keith