Pm 66 shutdown question.

[Jim Solomon]

I have a PM 66 3HP 1PH. It is 20 years old, but I purchased it from a lady who's husband bought it new but never got to put it together. I have cleaned the cosomoline off and was going to do some other things when I thought I better make sure it works:eek:So today I started it for the first time(since it was new). When I shut it down it came to a stop in about 4-5 secs. Is this normal, or should it coast down longer then that? Having never owned one I was curious. Also, it only say's in the manual about belt tension to "tighten the belts". How much deflection do you owners have on yours? Since they are so short it may be hard for me to check the deflection, if any is required. I know enough to not jam them tight and ruin the bearings. I think since these belts sat for 20 years in one postion I may be wise to purchase new ones, anyone agree? Thanks in advance for any suggestions/help.
Jim

[Brad Noble]

Not a bad idea for sure. If yours is like mine ('cept mine is 5 HP) there is very very little vibration, if any. If I ever have the occasion to tear mine apart anytime soon I'll probably replace my belts too. Maybe replace them with link belts??

Brad

[Heather Thompson]

Jim,

I have the same saw, mine is newer (2005), and there is play in the belts. I just reached in through the throat plate so do not have an actual measurement. As for the time at shut down, if there is no blade it takes 4 to 5 seconds, with a blade mounted I counted nine seconds.

Heather

[mike wacker]

Jim,

I have the same vintage PM66. From the sound of my saw when I shut it off I believe the motor has some kind of brake. Mine stops quite quickly around the same amout of time yours is.

As far as belt tensioning goes, I just replaced mine with belts from the local Auto parts store. I just put all three on (fairly challenging) and tightened them as much as I could. I figured with three belts I could get them too tight by hand.

Mike

[Pete Bradley]

If the belts are too loose, they'll look like a blur between the two pulleys. You want them tight enough that they don't vibrate, but no more. However, the bearings can take a lot of load so don't sweat it. If the belts are stiff after 20 years, you may want to buy a new set. A good industrial supplier like McMaster will have good quality ones. Link belts would be a total waste of money on a cabinet saw of this quality.

Congratulations on your new saw! This is a great score.

Pete

[Dwayne Watt]

Probably a good idea to replace 20 year old belts. Be sure to buy matched belts or you will have problems sooner than later. Matched belt sets are closely toleranced in length and section. Unmatched belts will likely have the loads concentrated on one or two of the three belts. This means premature belt failure will occur. Link belts are not necessary nor adviseable on a multi-belt pulley setup.
Nice catch on new old hardware.

[Jim Becker]

The faster the motor/arbor/blade combination comes to a stop when you turn the machine off, the safer it is. Many saw injuries occur after the power is cut when the operator reaches "too soon" for the workpiece and catches the still-spinning blade. Many high-end machines have braking circuitry in order to accomplish that end and the Euro standards even mandate it.

[Bob Feeser]

Would love to see some pictures of your saw. What kind of shape is it in. Are you one of the lucky few who have captured an older PM66 that is for all intents and purposes in factory new condition???


I have a PM 66 3HP 1PH. It is 20 years old, but I purchased it from a lady who's husband bought it new but never got to put it together. I have cleaned the cosomoline off and was going to do some other things when I thought I better make sure it works:eek:So today I started it for the first time(since it was new). When I shut it down it came to a stop in about 4-5 secs. Is this normal, or should it coast down longer then that? Having never owned one I was curious. Also, it only say's in the manual about belt tension to "tighten the belts". How much deflection do you owners have on yours? Since they are so short it may be hard for me to check the deflection, if any is required. I know enough to not jam them tight and ruin the bearings. I think since these belts sat for 20 years in one postion I may be wise to purchase new ones, anyone agree? Thanks in advance for any suggestions/help.
Jim

[Dave MacArthur]

Jim, I have an 89 PM66, and indeed there is a blade/motor brake on it. It does stop in 4-5 seconds, this is a great safety thing, and it is working perfectly--You should be very happy to have it!

Replace belts with link belts. The ones that sat will have a shape to them which tends to cause vibration. Alternately, ensure you shift all 3 belts "bumps" out of phase with each other so they self-dampen.

[Jim Solomon]

Would love to see some pictures of your saw. What kind of shape is it in. Are you one of the lucky few who have captured an older PM66 that is for all intents and purposes in factory new condition???
yes Bob, that's me from an earlier post. I bought the PM 66 and The DJ 20, both of them still crated for $2150. I have the DJ 20 cleaned up now and everything set. I was waiting for my Lee Valley 50" straight edge and the feeler guage. I then turned my attention to the saw. After putting it on the mobile base I was planning on making an extension table. Then the thought came to me, I never started this thing. So I wired it up and to my relief it started. It sounds like it has a brake on the motor when it comes to a stop. I just timed it, it takes 3-4 secs to come to a dead stop. My original post on this equip. is here
http://www.sawmillcreek.org/showthread.php?t=71986
page two has some before pics.
Jim

[Jim Solomon]

Jim,

I have the same vintage PM66. From the sound of my saw when I shut it off I believe the motor has some kind of brake. Mine stops quite quickly around the same amout of time yours is.

As far as belt tensioning goes, I just replaced mine with belts from the local Auto parts store. I just put all three on (fairly challenging) and tightened them as much as I could. I figured with three belts I could get them too tight by hand.

Mike

Same thing here Mike. I just counted the shut down with blade, out of 5 tries it took 3-4 secs for it to come to a complete stop. Don't get me wrong, if this is normal then I am very happy(safety). But if not then I may have an expensive repair down the road. I just tried ripping a 30 inch 2 7/8 square of red oak and even with a 3hp motor it sailed right through it. That was with a cheap craftsman tk rip blade. I have a Frued glue line and a WWI on order. I don't mind changing blades, at my age no production shop here:D
Jim
PS I just ordered new belts #6077004 OEM belts for $17.47 shipped last set. I was reading the original manual for the saw and it mentions a "centifrical switch". Wonder if that has anything to do with the shut down speed. Probably not.

[Bob Feeser]

Wow, like Bruce said, "Old American Iron in brand new condition at a great price, it doesn't get any better than that" (or something like that) Way to go. Great Find. Bob


yes Bob, that's me from an earlier post. I bought the PM 66 and The DJ 20, both of them still crated for $2150. I have the DJ 20 cleaned up now and everything set. I was waiting for my Lee Valley 50" straight edge and the feeler guage. I then turned my attention to the saw. After putting it on the mobile base I was planning on making an extension table. Then the thought came to me, I never started this thing. So I wired it up and to my relief it started. It sounds like it has a brake on the motor when it comes to a stop. I just timed it, it takes 3-4 secs to come to a dead stop. My original post on this equip. is here
http://www.sawmillcreek.org/showthread.php?t=71986
page two has some before pics.
Jim

[mike wacker]

Same thing here Mike. I just counted the shut down with blade, out of 5 tries it took 3-4 secs for it to come to a complete stop. Don't get me wrong, if this is normal then I am very happy(safety). But if not then I may have an expensive repair down the road. I just tried ripping a 30 inch 2 7/8 square of red oak and even with a 3hp motor it sailed right through it. That was with a cheap craftsman tk rip blade. I have a Frued glue line and a WWI on order. I don't mind changing blades, at my age no production shop here:D
Jim
PS I just ordered new belts #6077004 OEM belts for $17.47 shipped last set. I was reading the original manual for the saw and it mentions a "centifrical switch". Wonder if that has anything to do with the shut down speed. Probably not.

Jim,

Just so I'm clear, is that $17.47 for the set? And is a set 2 or 3 b3lts?

Thanks,

Mike

[Tom Veatch]

... I was reading the original manual for the saw and it mentions a "centifrical switch". Wonder if that has anything to do with the shut down speed. ...

That is most likely the switch in the motor that switches the start capacitor and winding out of the circuit when the motor reaches about 75% rated RPM. I wouldn't expect it to have any effect on the shut down process. See here (http://www.iprocessmart.com/leeson/leeson_singlephase_article.htm)for a short discussion of capacitor start induction motors.