MM 16 bandsaw shutting itself off

[alan tasoff]

My Minimax 16 bandsaw (about 12 years old, 5 hp, 3/4" Timberwolf blade) has been shutting itself off without being under heavy load, without overheating, and without activating the magnetic switch to the safety position. It starts right back up when the button is pushed. Tried adjusting bearings, cleaning them, reducing blade tension. It runs on its own 220 circuit, and cuts out whether or not the dust collector is on (on its own 220 circuit). It has never done this before, but some years ago did replace the switch because it was obviously malfunctioning. Not likely to be the door kill-switches, because the saw restarts immediately .
Any ideas appreciated. Is it possible my voltage has changed ? Once in a while, the 3 HP Oneida DC shuts off, and it also restarts right away.

[David Zaret]

check the starter. there is a little dial inside the switch that indicates max load before tripping, and i had a similar issue as you're describing. these switches notoriously fail... but in my case, i had to dial the max load up a hair. it's been fine since. good luck!

-- dz

[alan tasoff]

check the starter. there is a little dial inside the switch that indicates max load before tripping, and i had a similar issue as you're describing. these switches notoriously fail... but in my case, i had to dial the max load up a hair. it's been fine since. good luck!

-- dz

Thank you. I would never have thought of that.

[Jim Becker]

I will say that I had a similar issue with my slider years ago and in that case it did turn out to be voltage...a buck/boost transformer fixed that with Sam Blasco's guidance. But I my MM slider has a lot more electrical stuff in it than my MM16. (which was unaffected) I did have a switch go bad on the MM16, but that was early on and an easy fix. I do think it's worth exploring that, both for what David mentioned and to ascertain if there's anything actually "loose" relative to the switch. My CNC machine's main power switch had a clip work loose during shipment and it resulted in some intermittent power issues similar to what you describe. Once I figured out what it was, the problem went away permanently.

[Bill Dufour]

220 volts is about 10% low to start with. I bet the voltage sags lower under low so I agree low voltage is a problem.
Bill D

[Jim Becker]

220 volts is about 10% low to start with. I bet the voltage sags lower under low so I agree low voltage is a problem.
Bill D

Norma line voltage in North America is indeed 240v nominal. Many folks still refer to it as "220" for whatever reason. But I agree that if the OP's actual voltage is dipping below about 230v, it can absolutely affect many Euro type machines because they have inherent electronics that will shut down on low voltage. I'm not sure if the bandsaw does, but as I mentioned previously it was very much a problem for my MM Slider when it happened to me.

[Mick Simon]

In the event that the voltage is not the problem, another common issue is dust in the contacts. Blow it out well when you get it apart.

[Andrew Hughes]

One indication that the Op might have soft service is do the light dim when the saw starts.
This happened to me when I had 18 Laguna with a I think was a 3hp baldor motor. It was draw lots of amps for a few seconds and the voltage would drop. Lights would dim
At that time I doubt my service would start a 5 hp motor on a bandsaw
Since then I’ve had two upgrades to my service. A bigger line drop and transformer that I share with only 3 neighbors.

Good Luck

[alan tasoff]

One indication that the Op might have soft service is do the light dim when the saw starts.
This happened to me when I had 18 Laguna with a I think was a 3hp baldor motor. It was draw lots of amps for a few seconds and the voltage would drop. Lights would dim
At that time I doubt my service would start a 5 hp motor on a bandsaw
Since then I’ve had two upgrades to my service. A bigger line drop and transformer that I share with only 3 neighbors.

Good Luck

I am very grateful to all who replied with very interesting insights . Regarding the lights dimming, this happens with my 45 year old Unisaw ( 3 HP) on a separate "220" line, but I never gave it much thought, and the Unisaw never had the shut off problem. But, then, I doubt it has any electronics in the switch. Also, not knowing much about electrical stuff, I just use the term "220" as a generic for the category. When I did replace the MM 16 switch a few years ago (16 wires to it, as some of you may know), when I put it back together, sealed it shut to be dust free with metallic tape and it worked well for years. Loose connection ? if present, would it restart immediately upon demand ? Just "loose thoughts". Thanks again to all.

Alan.

[alan tasoff]

Regarding my original post of MM 16 bandsaw shutting itself off: On advice of a general contractor friend, he suggested I contact the electric company. A service person came within the hour, and checked voltage at the meter and at the transformer outside, but also replace some outside connectors that he said were many years old. Since then, bandsaw has been running under heavy load without a problem, and its companion Unisaw has not been dimming the lights on startup. This approach saved me a lot of work and possibly expense. Hopefully, this can help someone else someday.

[Andrew Hughes]

Good to hear Alan. I had almost the same experience when I started cobbling my shop together. Except I had to wait almost a years before anything was done by Edison.
Good Luck

[Frank Necaise]

Alan great to hear you resolved the issue and your other equipment also benefited from resolving the old connectors getting updated. Frank

[bob cohen]

I had something like this with former unisaw. One of their technicians suggested it was the electrical settings within the switch box, and it was. For some reason the ‘over-ride’ setting (the one that will turn the motor off at a certain amperage) was set too low at the factory. It was easy to change and it completely solved the problem. I may not be describing this correctly, but I do remember I had to go into the switch box and and reset something.