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Bandsaw Electric Motor Aneurism

  • 1.  Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 18:25
    Just as I was cutting laminations for a cut-off-bar, the motor on my bandsaw apparently suffered a ruptured aneurism. I know very little about electric motors. The black round thing on the top of the motor started smoking and black crud oozed out of it. Does anyone know what that unit on top of the motor is? I'm hoping that the problem is restricted to that black round thing - maybe just replace that and I'm home free? Although a question remains - was there something else beyond the black round thing atop the motor that caused the ruptured aneurism?
     
    Any electric-motor-knowledgable folks out there?
     
    It is an Italian motor on my Laguna bandsaw (made in Italy). It is 5 hp, 220V, single phase.
     
    Thanks


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    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------


  • 2.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 19:30
    Does not look good. Never seen anything like it. Any electric motor repair places in your vicinity?

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 3.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-08-2019 03:43
    Most likely it is capacitor burned. You can find one easy on eBay. Make sure it has 110 volts or more and same capacity ( micro farades). AC people have different types of thouse

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    Alexander Brusilovsky
    Richmond VA
    804-288-8878
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  • 4.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 20:00
    Terrence,
    It's a motor capacitor. You have a 50 – 50% chance the problem is limited to the capacitor. Try to read the value (there will be a digit(s) followed by a "uf" sign) on the casing. Google "motor capacitors" you will get many sites that sell replacements. If you can't read the value, Look for  websites that recommend capacitor values for 220v -- 5 ampere motors. There not expensive – about $20.
    Roger





  • 5.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 20:03
    Mr. Farrell,

    I think it's either a start capacitor or a run capacitor. My Delta dust collector motor had a run capacitor that went bad after ten years and there isn't a replacement part to be had. I bought a cheap Grizzly to tide me over in the meantime while I search the nether regions of the web for a replacement. As Delta wants in excess of $400 for a replacement motor with the new and improved capacitor I'll keep searching until the proverbial cows come home. United Electric Motor on Ida Street in Tampa should be able to sort it out for you.

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    Karl Roeder
    Pompano Beach FL
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  • 6.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 20:05
    Not an expert, but, looks and sounds to me like the wiring got loose or frayed and shorted out.  Ther ooze is probably the black insulation around the wiring that melted.  Unplug, unscrew cover and inspect wiring. Replace as needed. Occasionally open and check that screws are tight. Most electrical fires are caused by loose connections. 

    Gary Bruce
    Registered Piano Technician





  • 7.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 20:32
    I had the capacitor on my Minimax bandsaw have the exact same failure. I was able to get a capacitor from the manufacturer. I  forget whether I just read the ratings off the capacitor, or called minimax...but I know I did not replace the motor. I also cooked a bunch of them on so-called 5hp compressor motors for my 80gal compressor. I replaced 2 in a year, before I found a true 5hp motor and redid the pulley sizes.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 8.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 21:00
    Failing that, along the lines of what Peter mentioned, I have used a local electric motor shop to fix older but much better motors than what are out there now. I bet you'd be looking at $150 instead of $500 for a new whole motor. Problem is then, you would probably have to wait for the repair.

    If you are just doing cutoff bar laminations, a table saw would handle those rips fine. Even when I'm ripping full laminations these days, since I'm not running miles of the cuts, I first rip to the max on my table saw with a thin kerf blade, flip the board and do the same from the other side, then follow up on the bandsaw without a fence. The band saw follows the table saw kerfs quite well.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 9.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 22:18
    Oh, and uh, Mr. Farrell,

    Buckshot? Bandsaw motor burning up? Where exactly has that piano been all these years? You might want consult your parish priest or a local shaman or just burn some incense or something. Maybe light some sage and walk around the case three times backwards while intoning the name Braide-White? :-)





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    Karl Roeder
    Pompano Beach FL
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  • 10.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 22:33
    Ha, ha.

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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 11.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-07-2019 23:16
    Obviously, he's not using genuine Steinway parts!...the Gods will have their Revenge!!!

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 12.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-08-2019 02:48
    Many have already identified this as the motor starting capacitor.  However, before you invest in a new one make sure that the centrifugal switch inside the motor that controls the capacitor is not stuck closed.  Otherwise when you put on the new capacitor it will get fried when you turn it on.  Also, the capacitor can hold a dangerous charge for several minutes even after being unplugged. Touch both terminals with a screwdriver to ground it out.

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    Glen Hart
    Grand Junction CO
    970-434-5558
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  • 13.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-08-2019 15:47
    Hi Glen - How does one go about determining whether the centrifugal switch inside the motor that controls the capacitor is open or stuck closed?

    Thanks!

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 14.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-08-2019 18:43
    Remove the motor housing from the non pulley end. Remove the fan. Remove the dust cover if there is one. The centrifugal switch is on the armature of the motor and should slide right off (after loosening the screw). It kind of reminds me of a mouse sized bear trap. When the motor spins the switch opens.  You'll see how it works and if the contacts and the spring need attention.  The spring is disk-like behind the switch and can be bent with your fingers.  When  you turn off the motor, the centrifugal force lessens and the spring closes the switch so the capacitor can recharge.  When the motor is restarted the capacitor discharges which provides the needed extra force to get the motor spinning. If the spring is too strong the switch remains closed, frying the capacitor when the motor is started.  If it stays open the motor hums but won't spin.  FYI - I have the Laguna ReSaw Master which is almost identical to your saw but with a 5hp Baldor.  The switch should be the same.

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    Glen Hart
    Grand Junction CO
    970-434-5558
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  • 15.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-08-2019 20:07
    p.s. I should have used the word "rotor" instead of "armature".  The armature is  connected to the rotor.

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    Glen Hart
    Grand Junction CO
    970-434-5558
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  • 16.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-09-2019 17:13
    OMG!!!   Replaced the capacitor and my saw works much better than ever!

    I bought my saw about 18 years ago new. As far back as I can remember, to start my bandsaw, I've always had to crank the guides all the way up, grab the blade and set the blade in motion as I turned on the power. Often, it would take a few seconds too long to get up to speed and blow the fuse. I always just figured my fuse was too sensitive or the guides were too snug (although they weren't).

    After replacing the capacitor the darn thing just blasts up to full speed in a second or two - way faster then I can remember it ever moving - and I don't have to manually force the blade into motion. It just starts and goes to full speed on its own like a bandsaw should. I'm thinking that my capacitor blew (or at least got real weak) a good 15 years ago. I wish I had replaced it a long time ago!

    Thanks to all with all the suggestions. I'm back in business!

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    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 17.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-09-2019 18:27
    Terry,
    For what it's worth, here's what happened:

    Internally, the capacitor is made from two long strips of aluminum foil with a strip of paper sandwiched between them.  The aluminum pieces are electrical conductors attached to the two external wires (or terminals), and the paper is an insulator separating the two foil pieces.  The paper is saturated with a dielectric fluid (aka electrolyte), and then the foil plus paper is rolled into a cylinder and placed in the capacitor's metal or plastic housing.

    The capacitor's "value" (e.g., 100 mfd) is a combined result of the area of the foil, and the amount of dielectric fluid.  The value is specified for a particular motor to provide robust starting.  Over the decades, however, the dielectric fluid will slowly evaporate resulting in a reduced capacitance value.  On your band saw, this reduction initially showed up as lethargic starting.  But the secondary effect was to concentrate the power in the capacitor over a smaller area of foil; this plus the extended startup time resulted in excessive heating in the rolled up foil.  The aneurism popped when things got way too hot, and the paper burned through allowing the two foil pieces to short out.  Sometimes the whole assembly explodes violently; yours appears to have oozed instead before taking out the circuit breaker.

    Folks who play with old electronics -- like vintage 1930-1940 radios -- are all too familiar with the scenario!


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    John Rhodes
    Vancouver WA
    360-721-0728
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  • 18.  RE: Bandsaw Electric Motor Aneurism

    Posted 04-09-2019 18:55
    The third leg of my 3 phase converter is generated by a massive 7hp GE 3 phase, 50's vintage motor. The "capacitor" on this lovely bit of balast, is my foot. The foot rolls the arbor to start the spin, then I flip the switch. As far as I can tell, my own dielectric fluid is still working just fine.
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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 19.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-02-2019 09:33
    The MOST dangerous tool in a woodshop is the bandsaw ....quoted Safety lecture by my industrial wood shop instructor .... people get careless
    with the safety guides, fences, cut free hand etc.....

     I took night school wood shop classes and used every machine in the shop including huge planer, crosscut saws, sanders, mortising machines,
    table saws. Know you equipment and follow safety rules - if a machine is not working properly get it repaired properly or replace it. There is plenty of real junk, unsafe workshop equipment often inaccurate and not repairable.

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    James Kelly
    Pawleys Island SC
    843-325-4357
    ------------------------------



  • 20.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-02-2019 10:03
    One of the most dangerous tools for experienced and otherwise cautious people, in my experience, is the simple chisel. I saw a really bad scar on the left wrist of our metal shop instructor, otherwise an extremely gifted, experienced, and careful person.

    The temptation to use a chisel without clamping the work piece to a bench or putting it into a vise seems to overcome almost anyone eventually.

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    Susan Kline
    Philomath, Oregon
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  • 21.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-02-2019 10:51
    Well, then I guess the jointer would be a close second. I took woodworking in LA Trade Tech college years ago. There was this guy, you know the kind, always joking around, class clown. One day he was jointing a short stick thru the machine. The most dangerous sin on that machine is a short stick, because the other end of the stick won't be supported as you push it through. And you know, he lost his hand in there. No more Mr. Funny. Career finished. A very sobering day.. And then there's a shaper, with two blades, spinning at extreme speeds, right out in the open. Woodworking tools are indeed wickedly dangerous. Don't get me started on table saws.. You just have to be careless one time, and they will bite when you least expect it.
    Paul McCLoud
    San Diego

    James Kelly
    The MOST dangerous tool in a woodshop is the bandsaw ....quoted Safety lecture by my industrial wood shop instructor .... people get careless
    with the safety guides, fences, cut free hand etc.....

    I took night school wood shop classes and used every machine in the shop including huge planer, crosscut saws, sanders, mortising machines,
    table saws. Know you equipment and follow safety rules - if a machine is not working properly get it repaired properly or replace it. There is plenty of real junk, unsafe workshop equipment often inaccurate and not repairable.

    ------------------------------
    James Kelly
    Pawleys Island SC
    843-325-4357





  • 22.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-02-2019 11:36
    James K. wrote: "The MOST dangerous tool in a woodshop is the bandsaw..."

    Gee whizz, I would never had known!  ;-)

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 23.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-02-2019 11:44
    Be sure to view the bandsaw pictures full-size so that you can read the signs on the saw. Less so for the finger picture. Sorry, it's kinda gross - didn't realize it would be so vivid. Yuk.  :-(

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    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 24.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-02-2019 12:24
    Youze was lucky! That saw just got a taste. He's lickin' his chops now! A croc-O'dial!
    Paul McCloud
    San Diego



    Terrence Farrell
    Be sure to view the bandsaw pictures full-size so that you can read the signs on the saw. Less so for the finger picture. Sorry, it's kinda gross - didn't realize it would be so vivid. Yuk. :-(

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505





  • 25.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-02-2019 18:30
    Only a dull chisel is dangerous.

    I disagree with the bandsaw as being dangerous. I've been using one for 40 years and not a single mishap. I'm a little jealous of the 7 hp though, mines 5 hp and its enough for me.

    I would say that the automobile is the most dangerous because you can't predict the behavior of others.
    -chris

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    Troubles are Bubbles, and they just float away.
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Knoxville, TN
    865-986-7720
    ------------------------------



  • 26.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-02-2019 18:59
    My take on the relative danger of a bandsaw is that, compared to a table saw, router table, jointer, since it appears to be much less likely to throw things, kick back, bind, it can easily lead one to reduce or eliminate one's vigilance.  Its the tendency towards reduced vigilance that gives me the willies. I have not been injured by a bandsaw, but every time I approach it, I try to maintain adequate vigilance.

    Actually, after being injured very early on, in the 80's, on a router table, before I knew what I was doing, I have managed to avoid injury by my machines. Any injuries have come from a utility knife, of from air blowing cast iron dust into my eye, or cornea scratched stringing a piano.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 27.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-06-2019 10:39
    I actually disagree re the Bandsaw being "the most" dangerous tool in the shop, at least with regards to modern bandsaws with enclosed wheels, etc.  The most dangerous tool in the shop walks upright on 2 legs and is about 19 years old. As someone who regularly teaches people in the shop (from schoolchildren to novice adults) tablesaw/mitersaw/router/jointer are the biggest challenges, safety-wise. One safety ranking I have for tools is "how hard you have to work to cut your finger off". A bandsaw is perfectly capable of cutting your finger off, but you might have to push your finger through. The table saw is a deluxe machine, since it will do the work for you. (And then there's kick-back, etc.)   2 bandsaws in the shop here - 14" and 19".  Anyhow, I'm generally a fan of (well-tuned) bandsaws. If I could only have 1 power saw in the shop, it would be a good bandsaw.
    JF

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    John Fabel
    Adjunct Professor
    University of Massachusetts
    Amherst MA
    413-695-1380
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  • 28.  RE: Bandsaw Electric Motor Aneurism

    Posted 05-03-2019 02:15
    The instructor had been teaching for over thirty years and I trusted all of his knowledge and experience. The equipment in the shop was all major league, industrial grade. Every machine is dangerous but some more than others. Even with safety things in places like blade guards, fences, jigs there is always danger of kickbacks, loosing control of the work piece, forcing the cut, too high or too low a blade, not using push sticks to feed stock, too much sawdust on the floor etc. One night George the instructor had to have someone take him to the ER he was feeding some stock into the table saw and it caught the blade and threw it back with the sharp edges of the wood slicing his hand. Fortunately he was standing to the side following standard safety practices or he could have been impaled. A safety video we had to watch the first class of every term showed a kickback and the wood shot out of the saw like an arrow and stuck into the sheetrock.

    Always, always think the operation through in your head first if it seems unsafe it probably is. Some cuts need the help of a second person on the outfeed end , fences need to be aligned to the blades properly, blades need to be sharp and proper for the wood being cut . Operating machinery when you are tired, under the influence of alcohol or taking meds is a no no. If you wear watches and rings take them off. I own a ShopSmith that years ago was demonstrated in malls and you got free classes at the local store. Any demonstrator or instructor caught wearing a ring , watch, not wearing hearing and eye protection was fired on the spot. As piano techs we need all of our fingers.....

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    James Kelly
    Pawleys Island SC
    843-325-4357
    ------------------------------