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Fred Hubert
02-12-2010, 12:56 PM
This is applicable to the Craftsman, Ridgid and at least one model of the Steel City granite top table saws. There may be others of the same basic design/manufacture to which this would apply.

At issue is the way the motor is suspended from the arbor by the belt as the tensioning mechanism for the drive belt. While I don't believe this design is changeable, other design issues result in vibration. For example, poor OEM belt quality, and the fact that the pulleys are slip-fit on their shafts such that when the set screw is tightened it inherently creates an out-of-round situation as the pulley gets slightly offset from center.

Many Ridgid saw owners have reported marked improvement with a replacement belt. I found a local auto parts supplier that carries Gates and they can order a new belt for me for ~ $13.79 total after they make me cover the shipping. Not thrilled with that, but it beats the $19+ from elsewhere by the time shipping is factored in.

I took a close look at my saw to verify rib alignment on the pulleys (easy task with the door open or off and the tilt at 45 degrees), but when shining a flashlight in there I could see bits of sawdust in the ribs. Makes me wonder if a ribbed pulley is a good idea in such an environment. Particularly if such a simple thing as changing the belt can result in a dramatic improvement, it just stands to reason that saw dust in the ribs are less than ideal.

This is the nicest table saw I've ever owned, so I have no reference to compare to - what kind of drive system to 'better' saws use?

Following with my line of thinking, I found a discussion where a guy upgraded his Steel City version to a dual v-belt setup. He spent almost $100 doing it, but the majority of that was in the fancy belts he bought (the two pulleys were $17 each). See for yourself here: http://forum.canadianwoodworking.com/showthread.php?t=26355

In my case, I can hear the vibration of the motor, but the mass of the saw keeps it pretty rigid (no pun intended). In fact, not having a nickel handy I performed a penny test yesterday morning - the penny moved slightly on startup but stayed upright easily and only fell during shut down. Seems like the motor gets into a floating position rather quickly on startup, but during shutdown the offset pulleys begin to wobble the motor more and more as it slows and comes to rest on the pulley.

I'm considering an upgrade of the pulleys and want to decide on that one way or the other before I spend money on a new belt that may not work with new pulleys. But if some shutdown vibration is relatively common and has no negative effect on the saw then I'd appreciate learning that before wasting my money and time.

Anyone here with more knowledge than me on the subject that can offer up some good advice? If so, I thank you in advance...

Regards,
Fred

Chris Friesen
02-12-2010, 1:43 PM
Most cabinet saws use several V-belts, or a Poly-V belt. The real difference is that belt tension is fixed rather than rely on gravity.

A bit of vibration at startup or shutdown isn't a big deal as long as you're getting clean cuts while it's running.

Bill White
02-12-2010, 2:21 PM
Power Twist link belts may help. Local industrial sells it for $4.00/lf. Sure beats the heck out $8.00+ that I've seen in some catalogues.
Bill

Fred Hubert
02-12-2010, 4:28 PM
Link belts would only work after changing the pulleys to use a standard V-belt. The belt it comes with is flat, with six small ribs.

Fred

Van Huskey
02-12-2010, 6:34 PM
There are three basic blade designs used on "better" cabinet saws.

3 V belts
2 wedged V belts like the older PM 66
1 poly V belt

Overall the Poly V is the best for power transfer and vibration, second is the wedged V and the worst of the three is the triple V belt but up until the last few years it was the most often seen.

It actually sounds like you have a Poly V but the difference all comes down to the fact that there is no constant tension on the belt and that tension varies greatly during use.

I just don't know how much time I would spend reducing vibration on run down as long as it was not an issue while the saw was running.

Chip Lindley
02-12-2010, 7:23 PM
Fred, contractor-type tablesaws have been made in this manner for Eons! (but NOT with serpentine belts) The motor weight acting as belt tensioner is not changeable. I would think the serpentine belt would have less vibration than standard v-belts. But, it all depends on the machining and balance of pulleys involved. Sawdust in the ribs, as you discribe, is not an issue with v-belts or the PowerTwist.

I installed a PowerTwist belt (no new pulleys) on my old Rockwell Model 10 CS, and the difference was amazing. So much less vibration, that I kept the saw a few more years, before trading up and away from the CS-type forever.

If your TS is under warranty, and you cannot get satisfaction from the manufacturer, go with new balanced Browning pulleys and a PowerTwist belt. I don't think you'll be Sorry!

Chris Harry
02-12-2010, 8:08 PM
There was a thread about this on the ridgid forum, at least concerning the vibration during shut down. Its actually something called "re generation" from the motor.

That is different than vibration during running. I know my saw improved at least a little bit once I replaced the stock belt, but my stock belt was curled under itself in the packaging, so there was a nice kink in the middle of it that letting the saw run and warm it up would not fix. Replaced with a Goodyear from McMaster and there was a good improvement. The saw barely vibrates at all during running......a small "hop" when starting up, and what seems to be re-generation when shutting down. Overall Im not worried about it at all........yes using the motor weight for tension might not be the best way, but I didnt pay 3K for a shiny new Uni either :)

-Chris

Darin German
02-12-2010, 9:18 PM
but I have the steel city model 35920 table saw you referenced in your first post. I do get the click and slight shudder on shut down that you are referring to, but it has never been enough to cause me concern or pose a problem in day to day use. In fact whenever I first assembled the saw I was so psyched that I ran the nickel test several times and if I remember it only fell once and that was on shut down. I do believe the shudder is due to regeneration as previously stated. I'm not sure that our saws come with the same belt, but if a majority of the people complaining of the shudder say a new belt improves it I would go that route first before changing any pulleys. By the way I'm an automotive technician, and my experience has been that serpentine belts transfer power much better with less slippage or noise than standard v-belts. In fact I was very impressed that this saw was equipped with one. Sorry if this doesn't help much.:(

Terry Welty
02-12-2010, 10:22 PM
I am a huge fan of the "if it's not broke, don't fix it" philosophy. I have the Ridgid saw and it works great. A slight vibration is expected on shut down. I'm betting the saw cuts fine and probably has less vibration than most saws... Just don't balance your pennys and nickles on the saw and you'll do just fine... just my humble opinion...

Fred Hubert
02-13-2010, 9:07 PM
Thank you to everyone for the feedback. I am actually relieved - I was unsure if a pulley upgrade would be necessary so it is good to hear from experienced woodworkers that it more than likely isn't.

Fred