PM66 Arbor

[Heather Thompson]

As a number of you already know, I picked up a 2005 PM 66 the day after Thankgiving, have been working on getting it set up properly ever since. I checked the arbor for runout with a dial indicator, less than .001, thought all was good. Then I had a scary experience with a Betterly ZCI, ended up having a long chat with Tom at Betterley Tools and decided to look at the arbor a little closer. Out comes the dial indicator, set to zero and grab hold of the arbor flange, push down and pull up (.0025 deflection ). I weigh 130 lbs soaking wet and not really the body builder type, that 3hp Baldor motor on the other hand packs quite a punch, wonder what kind of deflection may occur at start up. Called PM tech support and spoke with Gary, they have no reference to specify acceptable deflection values, he suggests replacing the arbor assembly. Does anybody here have any numbers off of their saw or any thoughts on the topic?

Heather

Someday I may be able to make some sawdust, hopefully soon!

[Matt Meiser]

I assume you are putting the dial indicator base on the table top when you do this? Then leaning over the table and using it as leverage to pull on the arbor? Seems to me that you could see some movement doing that.

Have you put in a non-zci insert and just tried making some rip cuts with a good blade? If there's no scoring then I would look at another solution for the insert and get on with woodworking.

[Heather Thompson]

Matt,

You are correct with the dial indicator set up, actually use the Red Line X Point for setup and setting blade angle on critical cuts. I do not own a non-zci insert, I have used a Betterley for years and tend to do alot of small work (1/8" cuts for inlay type work). I can not do without my ZCI, bought the PM66 to get the finest in accuracy, my old Delta contractor saw was good but I wanted better.

Heather

[Brian Weick]

you may want to give this a try?
http://www.in-lineindustries.com/saw_pals.html
Brian

[Jim Becker]

you may want to give this a try?
http://www.in-lineindustries.com/saw_pals.html
Brian

Those will not work on a cabinet saw like a PM66.

[Matt Meiser]

Sorry, didn't mean that you should get rid of the ZCI forever, just make some test cuts without it. Since you only have the one insert, how about widening the slot in it so that the blade doesn't touch. My point is that if the the saw works fine without the insert touching the blade, then I'd look for a different insert that has the pin in the back like most.

Also, a thought just occurred to me. How bad is the runout near the edge of the blade? If you blade isn't flat, it doesn't matter how good/bad the arbor is.

I'm just not sure I'd be jumping into changing things on the saw based on an issue with one model of ZCI.

[Brian Weick]

Those will not work on a cabinet saw like a PM66.

sorry Heather,
Just trying to help- I forgot about the fact that it is a "cabinet saw" - my appologies,

there was a thread on here about this a weeks agao- same problem? I don't know where it is but if you do a search you may find it

thanks for pointing that out Jim-
Brian

[Heather Thompson]

Matt,

I have a number of WWII blades, tried three of them, still get lift at the back side of the insert, not a blade issue in my opinion. I talked to Tom at Betterley Tools and considered drilling and tapping a hole in the back of the plate, then screwing down a washer to act as the pin, but if I have an issue with the saw I would rather correct the problem at the source.

Heather

[Doug Shepard]

So was the scary incident because the ZCI tried to lift out because the slot was grabbing on the blade? I haven't had that particular issue but on every ZCI I've ever used on my PM66 I couldn't stand the rubbing sound so I suspect I've also got some minuscule runout. I solved it by just putting a thin dado set shim behind the blade and re-raising it through the ZCI to widen the slot up a tiny bit.

[Mike Marcade]

I think 2 and 1/2 thou of deflection with an end load is pretty darn good. I don't think this is the source of your problem.

Is that the total dial sweep from pushing down to pulling up?

Inside the bearing you could have close to .001" of radial internal clearance (if it is a C0 class bearing at the worst case) This means you could have close to .002" of deflection even if the shaft would be held at both ends. Adding in the fact that the shaft is cantilevered .0025 is just fine in my opinion.

[Steve Kohn]

I have a PM66 that I believe was manufactured in 2000. I have made all of my own ZCI's out of plywood. I am using the WWII blade. My homemade ZCI's also will lift up at start up of the saw. I solved the problem by putting a Z shaped table mounting clip on the back of the ZCI that stopped the lifting.

I also have installed the Shark splitter. This hooks over the ZCI and will also hold down the ZCI.

I have not checked runout, but the saw does everything I want it to do.

[Heather Thompson]

So was the scary incident because the ZCI tried to lift out because the slot was grabbing on the blade? I haven't had that particular issue but on every ZCI I've ever used on my PM66 I couldn't stand the rubbing sound so I suspect I've also got some minuscule runout. I solved it by just putting a thin dado set shim behind the blade and re-raising it through the ZCI to widen the slot up a tiny bit.

Doug,

Yep, the ZCI lifted alot the first couple of times, I put a make-shift sort of fence on my fence to make the testing a little safer, went to deck level at start up to observe , my LOML stood well off to the back of the saw to observe. He is not happy with it as nor am I. At this point I think that I will buy the new assembly and just bite the bullet, the price on the saw was fantastic so it is not a big deal, my safety is....

Heather

[Heather Thompson]

I think 2 and 1/2 thou of deflection with an end load is pretty darn good. I don't think this is the source of your problem.

Is that the total dial sweep from pushing down to pulling up?

Inside the bearing you could have close to .001" of radial internal clearance (if it is a C0 class bearing at the worst case) This means you could have close to .002" of deflection even if the shaft would be held at both ends. Adding in the fact that the shaft is cantilevered .0025 is just fine in my opinion.

Mike,

Thank you for the input, I do understand the issue of radial internal clearance to a degree, but I thought that by raising and lowering the blade numerous times that it would not be an issue. Other Creek members have stated that they have never had an issue such as I, any thoughts?

Heather

[Jim Becker]

Yep, the ZCI lifted alot the first couple of times,

Don't you have a nail or screw in the back of it that locks under the lip of the saw top to keep it from lifting? That's an absolutely necessary safety accommodation with any table saw insert, IMHO. I just used a simple cut off finishing nail for the MDF ZCIs I used to make for the cabinet saw.

You also should clamp down the ZCI for the "first blade raise"...clamp a board over it.

[Mike Marcade]

Mike,

Thank you for the input, I do understand the issue of radial internal clearance to a degree, but I thought that by raising and lowering the blade numerous times that it would not be an issue. Other Creek members have stated that they have never had an issue such as I, any thoughts?

Heather

In my opinion, any arbor with an end load such as that will have some amount of deflection. I don't think this deflection is causing your problem. Didn't you have to realign your table top? Did that do anything for you?