Need Help With 1 Hp Motor

This is great! Getting a Discussion going with lots of members (thanks all), about the ins and OUTS of a cheap H.F. saw. Based on all the replies, I think I will leave it as is, for now, start using the slower speed for more torque, and not expect too much out of this vastly overrated motor. Kwoodhands, I did change the trans. oil when I got it. Thanks for that, I actually used 140wt., as temp rarely gets below 40 F here. I do have a question for you, doesn't using cutting oil get oil and chips all over the wheels and inside the cover? Thanks to all, JR49
 
You asked about the three pulley positions. If you are cutting aluminum or brass you can use the highest speed/ conversely when cutting thick steel you need the slowest speed. Good luck with the motor == Jack
 
I have one of these saws I've been using for about 10 years now. The issue of the motor stalling is there and will happen. As others have said toward the end of the thread is to run it in the slowest speed. I agree 100%, that is the speed I run mine in. I cut everything up to including 4145HT in rounds up to about 4-1/2". I've even cut up some iron and aluminum into rectangular sections of nearly 7" square on my 4 x 6 saw.
One thing I have notice on the input shaft of the gear box, it is very hard to turn and it gets hot from running. This has a big affect on the motor stalling using it in the higher speeds. I don't think you are having a problem with the motor. It's more an mechanical issue...
 
Sounds like you have a bearing tight in the gearbox. On my old saw that was similar I removed all the old poor quality grease and replaced it with 90 w hypoid gear oil. Jack
 
JimDawson said:
This motor would be the replacement for it. http://www.harborfreight.com/1-HP-Agricultural-Farm-Duty-Motor-68288.html
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Jim, or whoever has more knowledge than I (nearly all). Although, thanks to the guidance I got here, I will not be replacing the motor presently, you sent me link to a motor that I could use as a replacement, without even seeing the saw. Could please share how you determine if a motor will be a correct fit to replace an existing motor in any machine (bandsaw lathe drill press etc.). Please include: When a spec says motor spins CW, or CCW, is that with shaft facing you or away from you?
 
JR49 said:
Jim, or whoever has more knowledge than I (nearly all). Although, thanks to the guidance I got here, I will not be replacing the motor presently, you sent me link to a motor that I could use as a replacement, without even seeing the saw. Could please share how you determine if a motor will be a correct fit to replace an existing motor in any machine (bandsaw lathe drill press etc.). Please include: When a spec says motor spins CW, or CCW, is that with shaft facing you or away from you?
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Great questions!

I was going by the stated 1 HP, and my knowledge. Those saws all take a NEMA 56 frame size motor (or possibly its rough metric equivalent). In hind site, I would probably recommend a 1/2 hp motor, rather than the 1 hp. No point in tearing up your gearbox.

Motors in general are sold by frame size, the most common up to 1 hp is the NEMA 56. I can't remember the frame number for the metric (IEC) motor in that general range. Once you go above 1 HP, then there are other frame sizes. For instance the 5HP on my compressor is a 182T frame. The frame specification will give you, shaft size, the mounting footprint, and physical size. All motors in a given frame will have the same specification regardless of HP.

Most motor rotation is listed facing the shaft, but who knows with Asian motors. If it is not reversible, the rotation is normally clearly stated. Most aftermarket motors are reversible anyway, so it really doesn't make any difference.
 
I have smoked a motor on one of these cutting a thick piece of aluminum. Prior to that I had the centrifugal switch fuse together. The motors can have problems. and the factory rating of 1hp is joke, but the physical dimensions should you need to replace it are the same as a NEMA 56 3/4 hp. I've got a couple of videos up that show problems I've had with my motors. The videos cover other things too, but I talk about motor problems in both of them. Hope it helps.

 
It's probably a cheap induction motor with a run capacitor that has failed. Since the capacitors are smaller than what is commonly used on a better motor and actually available, you may have to modify the cover to get a new one to fit. They are about $5-10 and a electric motor shop can supply. In general, teeth do not shed on a plate unless it is seriously low quality and has contaminants in it like you might find in a bed frame. My guess, you have overheated the cheap capacitor through no fault of yours. BTW, a saw that is blueprinted with a good blade will stall the motor before the blade will come off or strip teeth. Teeth are normally removed by cutting a hard thin wall tubing or getting something jammed between the deflector and the blade. Little wedges that you are cutting off have an uncanny ability to find the opening.
 
JR49 said:
My H.F. 4X6 bandsaw has the original 1 HP motor that it came with. Don't know how much use it's had as I got it used. Today, while cutting a steel plate 5" wide by 1" thick (this took longer than any piece since buying it), when it got almost to cutting through the bottom, the blade stopped. I assume, as it was cutting through a tooth caught and jammed the blade. I lifted up on the saw and the blade began moving again. I figured that the belt was slipping, because surely, the motor has enough power to slip the belt, especially since I run the belt pretty loose to make speed changes easy. But, to my surprise, it was not the belt, the motor was stopping, and as soon as I lifted the blade up it started turning again. I tried this a few more times and each time the motor stalled rather than slip the fairly loose belt. Are these H.F. motors that underpowered? The motor temp was about 138* F. with a laser thermometer, if that makes a difference. Is this motor junk? I would think with a little more power the blade should have pulled right through the cut. Does this motor have replaceable brushes, and would worn brushes cause the lack of power? I can probably fix it If you electrical gurus tell me what to fix. If need be, I can get a new motor, cause the saw is in really good shape, but I'd rather fix this one if I can. Please Help! Thanks, JR49
EDIT, Forgot to say, blade is 10-14 TPI, so there were plenty of teeth in the cut
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This motor on the HF 4x6 saw is only 1/3 HP, far below 1 HP, and is minimal quality. I have been using the same setup for over 20 years, with no problems, although I know the HF imported motor is bottom of the barrel stuff. This is a brushless induction motor, and you should just buy a USA made 1/3 HP replacement and be done with problems here. Be sure to check the gearbox lubrication level, and bearings all around. With moderate care this saw will continue to give good service.
 
I have a lot of steel cutting band saws over year most had 1/3 to 1/2 one very lard band saw had 3/4" motor
This saw only needs a good 1/3 to 1/2 hp motor
I have same saw with that motor I am waiting for day it dies and have the replacement on the shelf
I have cut lot bars 3/4 X 5 and 5" round stock with old I had it only had 1/3 motor form post tool about 25 years ago. Note I sold this and had to buy one from HF 7 years ago

Dave

JR49 said:
My H.F. 4X6 bandsaw has the original 1 HP motor that it came with. Don't know how much use it's had as I got it used. Today, while cutting a steel plate 5" wide by 1" thick (this took longer than any piece since buying it), when it got almost to cutting through the bottom, the blade stopped. I assume, as it was cutting through a tooth caught and jammed the blade. I lifted up on the saw and the blade began moving again. I figured that the belt was slipping, because surely, the motor has enough power to slip the belt, especially since I run the belt pretty loose to make speed changes easy. But, to my surprise, it was not the belt, the motor was stopping, and as soon as I lifted the blade up it started turning again. I tried this a few more times and each time the motor stalled rather than slip the fairly loose belt. Are these H.F. motors that underpowered? The motor temp was about 138* F. with a laser thermometer, if that makes a difference. Is this motor junk? I would think with a little more power the blade should have pulled right through the cut. Does this motor have replaceable brushes, and would worn brushes cause the lack of power? I can probably fix it If you electrical gurus tell me what to fix. If need be, I can get a new motor, cause the saw is in really good shape, but I'd rather fix this one if I can. Please Help! Thanks, JR49
EDIT, Forgot to say, blade is 10-14 TPI, so there were plenty of teeth in the cut
Click to expand...
 
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