PM 66 Restore Question

[Herb Berger]

:confused:I am currently restoring a 1980's vintage Powermatic 66 TS. I completely disassembled the machine. Stripped, sanded, and repainted all of the castings. Reassembled the castings. Installed new arbor bearings. Installed a new Lesseon 3 HP 1 PH 240 Volt Motor. Three new Power Twist Belts. Had the tables resurfaced. New start switch. Powder coated the cabinet.
I have the saw assembled to the point that I have put power to it. In doing so I have found that the arbor pulley, the arbor housing, arbor shaft and the motory pulley get verry warm. (At least I think it is very warm) After a 5 minute run with a blade in place the arbor housing, and arbor shaft rises in temperture from 75 degrees F to 120 degrees F.
I checked the pulley alignment and found the alignment to be dead on. The arbor assembly is a bit stiff, but not what I feel to be overly stiff. (Feels like what I believe new bearing would feel like. Smooth turning with just a bit of a drag.) The arbor has no play in any direction. I put the table top on and checked the arbor run out. It is less then one thousandth of an inch. The belts are not excessively tight. 3/8 inch or more deflection on both sides of the belt.
Does anyone know if this condition is normal? If it is not, any idea what may be causing the problem. I'm thinkning maybe the new belts need time to wear in.

[Pete Bradley]

Could be your bearings aren't properly seated. Take a rubber mallet and gently rap the end of the arbor a few times. If it suddenly turns smoother, you've got it. It's also possible you're seeing normal run-in of new bearings and a new pulley.

Pete

[David Christopher]

Herb, that sounds normal to me

[Bruce Page]

Herb, I had the same apprehension when I bought my Unisaw new several years ago. I also thought the spindle bearings were too warm after a long run. It’s been about ten years now and the saw is still going strong.
I’ll have to check it again to see if the spindle still gets as warm.

Bottom line, I think it’s normal for it to warm up.

Now how about posting some pics of that 66? :cool:

[Bob Aquino]

You might want to switch from those power twist belts to standard V belts. From what I just read over on OWWM, they are saying that its difficult to get 3 belts the same length and in a multibelt setup, that will cause more friction which means more heat.

Nowadays belts are manufactured to such close standards that 3 belts of the same nominal length will work as well as a "Matched Set". On my last saw refurb, a delta 12/14 I did note that the belts did get warm after about 10 mins of run time. I let the saw run without a blade for about a half hour to get things broken in. Good Luck.

[Cam Livingstone]

I noticed the same thing after converting a 3ph PM 66 to single ph with a new motor. I'm not sure if it is the belts or bearings but I took the following steps and it seemed to help.

Since the original motor was 5 hp and I was only installing a new 3 hp motor, I removed the center belt. Then I loosened the belt tension just a touch and applied some belt dressing. These steps seemed to help but I did not measure the before and after temp so can't be sure.

Anyway the saw is running fine with about 50 hours on it.

/Cam

[Herb Berger]

Thanks for all the help. I believe the heat I am seeing around the arbor and arbor pulley comes from the new belts and bearings. I have left the saw run for about 30 minutes. The arbor gets warm but seems to be less then when I first fired the saw up.

If anyone else has an old PM 66 let me know if the arbor casting and pulleys get warm when operating.

Thanks again for the assistance.

[Carroll Courtney]

Herb,if running it for that long and temp stays the same there is no problem.But,if the temp keeps climbing then there is a problem.Like others "I don't see no stinking saw"where's thee pics?--Carroll

[Herb Berger]

I am a bit challenged with the picture thing. I'm not much of a techno geek. I will try to post pictures.

Thanks for the response.