Aligning Top on Old Powermatic 66

[Steve H Graham]

I have a few questions on setting up my used Powermatic 66. Beware: it is highly likely that these questions will be stupid. I have used the search feature and read everything I could find; hope I'm not going over old ground.

1. I know how to bonk the table so the slot is parallel to the blade. I got some very helpful advice on that, and it gave me an excuse to order some cool stuff from MSC. But do I have to worry about how far forward or back the top is on the base? There's a little play in it. I would assume this doesn't matter.

2. I am going to make zero clearance throat plates with a router. For now, though, does it matter how far to the right or left the blade sits in the current slot? Should I just put it close to the center and be done with it?

3. When I took the top off to move the table, I didn't see the shims on the front side, and they fell out. I am fairly sure there were three on each front bolt, but it's conceivable that I'm wrong. How do I make sure I have it shimmed correctly? Someone told me that if I tightened the bolts without getting the shims right, I could permanently warp the top. I don't see how three points of contact could warp a top, now that I think about it. There are only three bolts.

You know, that guy may have been crazy. I've been worried about the height of the blade with respect to the table, but you change that every time you crank the wheel, so it can't mean anything. And I was worried about the slope from front to back, but a blade is circular, so one angle is the same as another as far as it's concerned. Maybe the only purpose of the shims is to make the table more or less level. I guess you could have a top that is sloped diagonally, but I would think a square held up to the blade would make that obvious.

4. I installed the wings by eyeball, because I didn't know I was supposed to use clever tools to do it. I can't feel any change in height as I run my fingers across the gaps. Should I loosen the wings and line them up with tools (like a piece of jointed wood and some clamps), or should I be satisfied with a difference I can't detect by feel and sight?

5. Is there any point in polishing the top? It's nearly free from dings and pits, but it's black. I rubbed part of it with Sheila Shine to see what it would do. A lot of crap came off, but the appearance of the table was unchanged, so I guess there's a fairly serious layer of oxidation and whatever on there. It may be preventing rust. It reminds me a little bit of a seasoned skillet.

Thanks for the help.

I can't run this silly thing yet; the plug is a 30A job, and it doesn't match my 50A receptacle, so I had to order a new plug. If anyone else is in the same boat, let me advise you to Ebay it. On the web, this part (which is ridiculously simple and presumably cheap to make) sells for $60, but I am having one delivered for about eleven bucks.

People have advised me not to cut up the extra-long rails. I'm still thinking it over. If I could create a cabinet under it and make the entire thing roll, I could conceivably keep the rails. The only benefit I see in this is that I would have space to plop things on while I worked, as well as storage. It would be nice to have a place to leave my incredibly huge miter saw. I am reluctant because it was insane to buy this giant saw to begin with, and it seems like turning it into an eight-foot-long aircraft carrier in a two-car garage is a little psychotic.

By the way, let me ask. Is a huge sliding miter saw of any real use in woodworking? I wanted it primarily for cross-cutting stuff that was too wide to fit on my 10" compound miter saw. HD put it on sale, and I felt like I absolutely had to buy it.

Finally, MERRY CHRISTMAS.

[Neal Clayton]

1) it might affect how high you can get a dado blade later on by whatever you're off, but that's about it, and that'll be minimal.

2) close enough. again this would only affect a dado blade with the factory dado insert, as long as it doesn't hit the insert with a full dado stack on it (and you can't have that much slop no matter what you do), it doesn't matter.

3) just put them back like you think they were, and test the table for flatness with a level after tightening them. worst case scenario is you're wrong and have to do it again.

4) feel and sight is fine, imo. again just lay a level across and make sure it's flat, that's enough

5) that's part of the charm of old iron ;). you want to put some sort of sealer on it (i personally use boeshield) but otherwise it'll be fine.

i don't care for the 12" miter saws since they're too bulky to move around, an added benefit of the 10" saws besides that is you can use the same crosscut blades on them that you have for your table saw. but that's all personal preference really.

[Steve H Graham]

Thanks for the reply.

I don't think I would have bought the miter saw, had I realized I was going to go crazy and buy a cabinet saw soon afterward. The appeal was that I would have a saw sitting in my garage at all times, ready to make any cut up to 13.5" long.

[Neal Clayton]

and if i'm reading you right you have a very long fence rail, too long for your shop?

i had a similar situation when i bought my PM66, the previous owner had a 9.5 foot fence on it (he was a boat builder), and i didn't have room for it either. i kinda took the same idea that others have suggested to you. it seemed wasteful for me to cut it, so i sold the 9.5 foot fence to a guy at a local speaker shop who needed it to make those extra long boom boxes for folks who were bringing big SUVs in to his shop for sound systems, and bought a new aftermarket fence with the proceeds, but that's just my good samaritan nature i guess ;).

[Steve H Graham]

The rails are 98" long. I am positive I won't need that length for anything I cut, but the added work room sounds nice.

The problem with finding a new home for the rails is that it will end up costing me a lot of money, whereas sawing down the old ones is free.

[Neal Clayton]

might not cost you anything, didn't cost me anything to swap out mine. i just put the old one on craigslist for a price equivalent to the new one i wanted, and everyone was happy. the buyer got what he wanted and i got a new one ;).

[Steve H Graham]

Looks like I was wrong about the wings being level. I can feel a little edge on each joint when I run a fingernail over it.

[Ted Shrader]

When I took the top off to move the table, I didn't see the shims on the front side, and they fell out. I am fairly sure there were three on each front bolt, but it's conceivable that I'm wrong. How do I make sure I have it shimmed correctly? Someone told me that if I tightened the bolts without getting the shims right, I could permanently warp the top. I don't see how three points of contact could warp a top, now that I think about it. There are only three bolts.

You know, that guy may have been crazy. I've been worried about the height of the blade with respect to the table, but you change that every time you crank the wheel, so it can't mean anything. And I was worried about the slope from front to back, but a blade is circular, so one angle is the same as another as far as it's concerned. Maybe the only purpose of the shims is to make the table more or less level. I guess you could have a top that is sloped diagonally, but I would think a square held up to the blade would make that obvious.Steve -

You are correct that the shims don't really come into play for 90° cuts. As long as the fence and blade (or miter slots and blade) are aligned you will be fine. When you tilt the blade for a bevel cut, then the front of the blade and the rear of the blade must be in the same position relative to the table. You may be pushing "uphill" or "downhill" into the blade. If the front and rear of the blade both don't fall in the "same" kerf, you will get burn or scuff marks from the rear of the blade.

The axis of rotation of the trunnion must be parallel with the plane of the table top as the blade tilts. Start with the shims installed under the two front bolts and make some test cuts at a 45° bevel and check your results. Tweak from there. Chances are it will be right on the money.


Is there any point in polishing the top? It's nearly free from dings and pits, but it's black. I rubbed part of it with Sheila Shine to see what it would do. A lot of crap came off, but the appearance of the table was unchanged, so I guess there's a fairly serious layer of oxidation and whatever on there. It may be preventing rust. It reminds me a little bit of a seasoned skillet.Black rust (Fe3O4) is good. Rub some more of the cleaner over the rest of it and then give it a good coat of Johnson's paste wax.


People have advised me not to cut up the extra-long rails. I'm still thinking it over. If I could create a cabinet under it and make the entire thing roll, I could conceivably keep the rails. The only benefit I see in this is that I would have space to plop things on while I worked, as well as storage.Build the cabinet, you will use it. Incorporate a router at the end of the wing and save making a router table.

My PM66 fence tubes are 84" long giving a 52" capacity to the right of the blade. The saw is on a Powermatic base and moves fairly easily when required. Also kept in a two car shop . . . e r r r, I mean garage.


By the way, let me ask. Is a huge sliding miter saw of any real use in woodworking? I wanted it primarily for cross-cutting stuff that was too wide to fit on my 10" compound miter saw. HD put it on sale, and I felt like I absolutely had to buy it.I shifted from a DeWalt 12" CMS to a DW718 12" SCMS to get the extra cutoff capacity for angled cuts. Build a sled for your table saw and it will make precise 90° cuts all day long.

Regards,
Ted

[Cary Falk]

3) I didn't see it mentioned but if the top is not shimmed correctly the blade will not stay parallel with the miter slot when moved between 90 and 45 degrees.

[Dick Strauss]

Steve,
Rick Lucrezi is looking for a longer fence. Maybe a swap might would make sense...????
http://www.sawmillcreek.org/showthread.php?t=99927

[M Toupin]

3) I didn't see it mentioned but if the top is not shimmed correctly the blade will not stay parallel with the miter slot when moved between 90 and 45 degrees.

As Cary has pointed out, that's exactly the purpose of the shims which look like regular old washers, but are actually precise thicknesses. In order to get your saw cutting parallel at both the 90 & 45 deg you need to get the shims back in their original positions and everything properly realigned. The manual for the grizzly G1023 series saws has a good section that explains how to adjust the parallelism which is the same basic method for most all like engineered cabinet saws. There's no quick or easy way to do it, it's going to take a lot of time and trial and error it git it back in alignment. Pick a day when you can spend sit down uninterrupted and bite the bullet and do it right. Hind sight's twenty twenty huh...

Mike

[Steve H Graham]

This is all great information.

I think once my 50-amp plug arrives, I'll do a few test cuts and see what kind of shape I'm in. If I was right about those shims, I may be in the clear.

When I saw this machine on the web, I was in the process of converting a huge desk into a router table, and it happens to be long enough and wide enough to cut up for a table saw extension. I guess I could use that to get things up and running--using the 98" rails--and if I like it, I can use it to work the wood for a better extension and cabinet.

The desk has steel legs and supports, which will be of no use once the top is turned into an extension. Maybe I could cut those up and weld them into extension legs.

[Chip Lindley]

If you plan on a mobile configuration for your PM66, the desk may be a bit much as an extension/router table. If you have real estate to provide a stationary spot for the saw, not an issue.

50A plugs (normally for kitchen ranges) are huge and your 10 or 12ga saw cord may not attach securely to the plug. I might suggest you make a short *pigtail extension* using heavy 8ga wire with the 50A plug at one end, and a female plug to fit your saw at the other. This might be a more secure configuration. Just a THOT!

[Steve H Graham]

If you plan on a mobile configuration for your PM66, the desk may be a bit much as an extension/router table. If you have real estate to provide a stationary spot for the saw, not an issue.

50A plugs (normally for kitchen ranges) are huge and your 10 or 12ga saw cord may not attach securely to the plug. I might suggest you make a short *pigtail extension* using heavy 8ga wire with the 50A plug at one end, and a female plug to fit your saw at the other. This might be a more secure configuration. Just a THOT!

It didn't occur to me to look at the gauge number when I was fooling with the wiring, but it's heavy. I can't tell 6 from 8 from 10 by memory. I'm sure it's not thinner than 10, because the cord is almost as big around as a finger. I'll know whether it works with my new plug, as soon as the plug arrives.

It might have been smarter to add a dryer receptacle to my 220 circuit, so I won't have to alter any more cords in the future. Adding a wall receptacle would take half an hour. Maybe I should just do that and eat the cost of the NEMA plug.

The desk is just a slab with legs and a couple of horizontal supports. It's really more of a table than a desk. Everything but the top will come off, if I decide to try to use it as an extension.

I can't set the saw in one spot permanently because the garage isn't big enough. If I could get it to where it would move about six feet without much trouble, it would be fine.

Can't hurt to give it a shot. The alternative is to put it by the curb for the trashpickers.