Converting a Bandmill from Gas to Electric
Advice on mounting an electric motor on a bandsaw mill. March 9, 2010
Question
I would like to convert the Norwood LumberMate 2000 into a 10 HP electric powered motor (3 phase, 50 hertz... yes, 50 hertz). Norwood told me that they could sell me the LM2000 without the gas engine so that I could install the 10 HP electric motor on it.
The problem is that they do not know how to convert this. They said one customer did a conversion from gas to electric and they did not know how it was done.
However, Norwood gave me the following 10HP electric motor specifications:
10 HP
215T frame size
3 phase/50 hertz
Pulley/sheave size 4.95"
Motor length not to exceed 17"
Motor weight not to exceed 104 lbs
I called Leeson and checked their 10 HP Lincoln motor. They could not come up with a motor that weights 104 lbs and their motor of 10 HP weights about 150 lbs. Has anyone performed the LM2000 conversion from gas to electric?
Forum Responses
(Sawing and Drying Forum)
From contributor S:
I've never done a conversion on the machine you mention, but the rule of thumb is that it takes twice the hp on a gasoline engine than it would on an electric motor. So if your current gas engine is rated at 20hp, you will only need a 10hp electric motor.
If the manufacturer does not have a conversion kit, then you'll probably need a welder to build a mounting plate for the motor. You can also find ready-to-use motor mounts that have the belt tension mechanisms built in. I think they are commonly called "jack plates" - check with a good bearing supply shop.
Ask an electrician, but you can probably run a 60 hertz three phase motor at 50 hertz - doing so will reduce the rpm (and possibly the hp). This may require rethinking your pulley diameter. Also you may have some safety interlock devices on your machine that you'll need to rework/incorporate - this is likely a job for a competent electrician.
From contributor C:
For the 50 hertz motor, you can use a variable frequency drive (VFD) to achieve this, or run a motor that runs at the correct rpm. (All a VFD does is vary the hertz to vary the speed of the motor.) Do you know what RPM the motor needs to run at for this size of pulley? You may be able to use a larger/smaller electric motor and simply change the pulley size accordingly.
From contributor G:
I have done this conversion to my LM2000 using a 5hp 1 phase WEG motor. The power was about equal to the 13hp Honda. I forget the motor frame size, but all I had to do was file the existing mounting slots a little wider. I used a 5.5 inch pulley. (I would suggest using an electric clutch instead of pulley.) From then on it was just basic wiring. No other changes were needed except to tighten the coil spring a couple turns because the electric motor was heavier than the Honda. The picture below shows the truss I used for the wire to the mill.
Click here for higher quality, full size image
From the original questioner:
Thank you very much. That was exactly what I was looking for. Do you have a picture with a closer look of the sawhead and the way the motor is mounted on it?
From contributor G:
Here's a picture of the motor. This one weighs 110 lbs. If I remember right (it's been 7 years) I put the 2 bolts in the slots on the right side, facing the pulley. I then lined up the motor and marked the left slots and filed them enough so the bolts would be straight. I think I only had to file about a 1/4 inch. The frame type is 184T. I would think any frame bolt pattern would work.
Click here for higher quality, full size image
From contributor A:
How big a log can you cut with that electric motor? I have wanted a sawmill for years. I have a 7.5 hp phase converter in my shop and could run a wire to the sawmill. Guys are always saying 7.5 isn't enough.
From the original questioner:
Thank you. Do you think we may need a mounting frame which is also sold by the motor manufacturer?
From contributor G:
I don't know what you mean by needing a mounting frame. Maybe 3 phase are different?
Contributor A, the electric motor will handle a log of the mill's capacity. The log in this picture was too big... Had to do a lot of trimming with the chainsaw to clear the posts and blade guides.
Click here for higher quality, full size image
Here's another big pine that measured 32" on the small end. The bad part is the blade only goes up 24". I had about an 8" slab that I had to resaw later. The 5 hp electric motor is a little slower than the 13 Honda in logs this size.
Click here for higher quality, full size image
From contributor E:
We (EastQuip.com) have conversion kits available.
Click here for higher quality, full size image