Replies

1. 
   RickL | Sep 05, 2006 09:56pm | #1

   http://www.saldet.com/     Ambitech brakes have been around for years. Last I knew they started around $350. Have you contacted your local motor repair shop? There is nothing geared toward the PM 66 specifically. The timiing on  a brake is critical. Stopping too fast will cause the arbor nut to loosen. The Ambitech brake has a timing adjustment to keep the arbor from loosening. If your motor was three phase you could use a VFD and program it to reverse slightly for a few seconds. The belted saws don't take that long to stop. You should see some of the direct drive saws. We would take a 15 minute break and come back and the saw was still spinning.

2. 
   TKanzler | Sep 06, 2006 12:03am | #2

   Many single-phase Baldor motors do that already, though not necessarily on purpose.  When the centrifugal switch closes as the motor slows, it regenerates and causes a relatively rapid shutdown.  Delta used to make (maybe they still do) a low-voltage starter with a regeneration circuit such that you could wire one of the start winding leads through it to prevent the motor from regenerating by breaking the start winding circuit whenever the contactor is open - no continuity, no regeneration.  I have one of those starters standing by to go on my 12" RAS, if I ever get around to finishing it.

   Since most PM66's have Baldor motors, you might want to check the wiring diagram or schematic to see if the start winding also goes through the motor control.  If it does, you can jumper it to allow it to regenerate, if the motor is so inclined.

   p.s. I have 3 Baldors laying around here, including one 1200 rpm motor on a lathe, and they all do it.  I've experimented with opening the start winding leads after the motor starts, then shutting it off, and sure enough, no regeneration so no rapid shut-down.  No other motor brands that I'm aware of do this.  Go figure.

   If you want to know more, send me an email, and I'll see if I can find an on-line wiring diagram showing how this works.  I believe someone on OWWM has addressed this, also.  I even advised someone on another forum on how to make his PM66 NOT shutdown rapidly, which worked.  Perhaps yours is wired to prevent it, and can be reversed.

   Edit:  One quick way to check the wiring is to open the cover on the motor terminal box, and see if one of the start winding leads (either number 5 or number 8) is connected to the cord going to the motor control, making three hot leads plus a green ground to the motor control.  If it is, then the control is probably preventing regeneration.  If not, and both the 5 and 8 leads are connected to the other leads inside the box, then it's possible that particular model of motor won't do it. 

   Be seeing you...

   
   

   ---

   Edited 9/5/2006 5:07 pm ET by TKanzler

1. 
   Jimma | Sep 08, 2006 09:22pm | #3

   Many thanks to you and Rick for your suggestions. I do have a motor repair company near me and I'm going to pay them a visit. The $350 solution may be a good one, but first I'll check out the Baldor winding thing. How come nobody else is unhappy with this problem? I bet every cabinet saw on the market comes with it.

1. 
   mudman | Sep 10, 2006 11:33pm | #8

   My Unisaw stops in 30 seconds I guess. That really dosent seem like a problem. There is no way I could make a cut, kill the motor, grab the wrenches and another blade and still have the motor spinning. My 14" RAS on the other hand will spin for a few minutes, with a 10"x3/4" wide dado set on the arbor it spins for ever. That I find anoying.Pardon my spelling,

   Mike

   Make sure that your next project is beyond your skill and requires tools you don't have. You won't regret it.

1. 
   John_D | Sep 14, 2006 04:18am | #9

   I wish my Unisaw had a brake, as there are lots of thin, short cuts where the offcuts sit next to the blade trapped by the pawls and I wait between each cut for it to coast down (in cases where I can't just push it through with the next cut).  Not a big deal, but it'd be nice.My goal is for my work to outlast me.  Expect my joinery to get simpler as time goes by.

3. 
   Lataxe | Sep 09, 2006 09:24pm | #4

   Jimma,

   Apologies in advance for not answering your question, but....I can't resist pointing out that a built-in electronic brake is standard on the vast majority of European saws.  Mine comes to a stop in a few seconds.

   This seems to be yet another omission of American TS makers; another feature that Americans will have to shell out for should they wish to add it on.

   Apologies again for not helping you answer your question; unless you want to buy a European saw, of course - inclusive of blade-following riving knife, sliding cross cut table, unobtrusive blade guard, blade brake, arbor lock and so forth and so on. If only they had the sawstop trip mechanism, they would be near-perfeck. :-)

   Lataxe

1. 
   Jimma | Sep 09, 2006 11:46pm | #5

   Yes, I suspected that European multifunction tools had brakes and, like most American craftsmen, if we didin't have so much invested in dedicated single-function tools we would probably buy them also. I had a radial-arm saw one time that did have an electronic brake. Some of the newer American-branded table saws are arriving and riving. A friend of mine uses a European saw in his custom entry door business because of its horizontal mortiser. Very nice machine.

4. 
   sapwood | Sep 10, 2006 06:21am | #6

   You could always trade in for a SawStop tablesaw. To stop it all you gotta do is touch it. How much quicker could that be?

1. 
   Jimma | Sep 10, 2006 05:11pm | #7

   Yeah, but then I'd have to buy a new Forrest blade and stop assembly and no-telling what else.