I've been looking for a new horizontal band saw. I found a good deal on a wellsaw 1118. The guy said it was single phase.....my wife picked it up for me.....it is 3 phase. I am pretty good at electrical work but know nothing about 3 phase. Do I just look for a motor with similar specs as the 3 phase motor and go with it?
band saw motor replacement 3ph - 1 ph
- Thread starter alex2929
- Start date
theoldwizard1
Well-known member
Yes ! As long as the motor frame (mount) is the same and the HP is the same, it won't be an issue (except wiring)
Or leave it 3 phase and buy a VFD and now you will have a variable speed band saw !
Or leave it 3 phase and buy a VFD and now you will have a variable speed band saw !
Walkers
Well-known member
Another option is a Rotary Phase Converter. I have built several with a 3 phase motor and a kit from ebay for a hundred bucks.
... and, if the frame is different , and you have the room, you can make new mounting holes .
biggest thing I see is keeping the rpm to the driven pulley the same .
biggest thing I see is keeping the rpm to the driven pulley the same .
Thanks for the replies. I’ll probably go the new motor route. That seems the simplest. This is WAY more saw than I need but the price was right. It has a 3hp motor on it. I’ve seen some other used ones with 2hp. Would that work ok? This is strictly for hobby use
cvairwerks
Well-known member
Realize that the 1118 uses the motor as part of the balance system. Change to motor and you will need to reset things if the motor weight changes more than a pound or two.....
Zeke
Well-known member
3 HP for a band saw is a lot. Must be a brute. Is there a cooling flood system on it? Maybe they were running it fast. As for the weight, I wouldn't have thought of that off the bat but any kind of make up ballast will work. Put a lifting weight on it. Actually it would be kinda nice to slip weights on and off for different materials. I'm talking in ounces.
wyliesdiesels
Well-known member
deleted...
wyliesdiesels
Well-known member
yikes the wiring needs to be cleaned up a bit at the top.Will some of this stuff need changed too? Motors definitely aren’t my strong spot.
yes the heaters in the overload relay block below the contactor will need to be changed if you change the motor
also you dont need all 3 poles since its single phase. you will need to make sure whatever 2 poles you use will have the line in from the breaker going to them. the control wiring for the coil will need to be rewired as well depending on which line in lugs it connects to...
tool_scrounge
Well-known member
does the saw have a shut off at the end of the cut? If it does and you say you are not good at electronics, buying a rotary phase converter is the simplest solution.
tool_scrounge
Well-known member
Is the coolant pump 3 phase also? if so, do you intend to use the pump?
tool_scrounge
Well-known member
what voltage is the pump motor?
wyliesdiesels
Well-known member
The controls wouldnt be 3 phase since all youre doing is switching a single phase coil.
dave*99
Well-known member
A VFD is the easy solution here. Read up and price it out before you jump into replacing the motor. I haven’t bought a VFD in a while but the guys here will advise you on the correct brands.
jar944
Well-known member
I'll pile on the vfd suggestion. It's going to be far cheaper to get a name brand vfd than a new motor and mag starter / contactor.
The down/off switch is also a simple thing to wire into the vfd 3 wire external control circuit.
The down/off switch is also a simple thing to wire into the vfd 3 wire external control circuit.
fitter30
Well-known member
Look at the frame number of the 3 phase motor see if a single phase has the same number or call a motor shop they also make adapter base mounts. The sq d size 0 starter you have is rated to 18 amp so if the single phase motor is under that amps can purchase two heaters that are the correct amps and wire to the two outside poles and leave to middle old heater in.
NEMA type starters do not work that way, they are rated for varying horsepower depending on the number of phases & the supply voltage, a NEMA size O is rated for 1 HP at 115V, 2 HP at 230V single phase, a single phase motor only requires 1 heater coil/thermal element, & when using a SQ D 3Ø overload relay in a 1Ø application, they offer a jumper kit to bypass the heaters in 2 of the poles, it is cheaper then buying 2 coils to use the kit, that way only have to buy 1, since the overload relay will not reset without either the heaters or heater & jumpers in place.
fitter30
Well-known member
Yes their rated for hp but they list overload amps. If it was in a industrial 3 ph setting not someones workshop a 1 ph proper starter would have to be purchased. I'll take the heavier contacts nema vrs definite purpose contactor with thermal overloads especially when the starter overloads are heaters.
Boy this motor stuff is over my head. It intrigues me though. I have a motor shop getting a 1.5 hp motor ready for it. It was slightly used and he was going to go through it first. He thought it would be done later this week and would help me wire it up. He thought the starter/heaters would work for the motor. 
As long as it's run at 240V, and the necessary mods are done to the overload relay to use for single phase, it will fine.Boy this motor stuff is over my head. It intrigues me though. I have a motor shop getting a 1.5 hp motor ready for it. It was slightly used and he was going to go through it first. He thought it would be done later this week and would help me wire it up. He thought the starter/heaters would work for the motor.