Friday, April 17, 2015

Bandsaw "adjustment"

Last year, my family and I moved from Washington (state) to Maryland.  The rental house we moved into has a 2 car garage, so that became my shop.  I have 4 big tools with 220 volt motors.  The tablesaw, the bandsaw, the air compressor, and the dust collector.  Unfortunately, and to no surprise, the garage of the rental house did not have 220 volt circuits.  I decided to mothball the air compressor and dust collector.  I have a small pancake air compressor I could limp by on, and I could purchase a dust collector that operated on 110 volt.  But I wanted the bandsaw and tablesaw operational.

I got a quote from an electrician to install a 220 volt circuit in the garage.  The existing electrical panel is on the far end of the house from the garage.  The quote came back at $1500 if I dug the 18" deep trench across the length of the house.  That idea quickly died.

Instead, I decided to swap the motors on the tablesaw and bandsaw for 115 volt motors.  The tablesaw, a circa 2000 Powermatic 66, was fairly easy to swap.  Maybe I'll post about that another time.

The bandsaw, an 18" Jet JWBS-18X-3, was a bit more challenging.  It seems that the manufacturer chose to use a custom motor with non-NEMA face mount, so that the bolt holes do not line up with NEMA motors.  Brilliant.  So when your motor craps out on you, you are forced to buy a replacement from them.  Or do what I did as I describe below.

Overall, the motor replacement on the bandsaw went like this:

  • purchase a 115 volt, 2 hp NEMA motor
  • purchase a new sheave
  • purchase new magnetic starter
  • have a custom motor mount made
  • enlarge the through hole in the side of the bandsaw for the motor
  • install everything
The motor I bought is a Leeson.  See the picture of the nameplate below.  This is a NEMA 145TC frame.  This motor can either be mounted via the bace or via the face.  I used the face mount.  Ebay is a great resource for things like this.

The original motor had a non-standard motor shaft, too, so I had to buy a new sheave (the pulley that goes on the end of the motor shaft that the belt rides on).  For the motor I bought, I got a BK-28 sheave with 7/8" bore.

The original starter on the bandsaw (the switch, if you will) was for a 220 volt motor.  So, I had to buy a new magnetic starter.  Grizzly had a good one... the G8291 magnetic switch.

Now came the interesting part.  How to mount the new NEMA motor to the bandsaw, given that the original motor mount was not for a NEMA motor bolt pattern.  I discovered a fantastic service online.  This is an online machine shop, out of New Jersey I think.  Using their free 3D modeling software, you design your part, cost it, pick materials, and submit it all online.  I was able to choose an adequate material that was strong enough but inexpensive.  Something steel.  I am not a metallurgist.  The cost, including delivery, for my custom motor mount bracket was around $75.  I ended up priming it and painting it black with spray can paint.  It fit PERFECTLY.

The next problem was the hole in the side of the bandsaw for the motor to go through.  You might be able to tell from the photo above that the bolt holes for the motor in the new mount plate were covered up by the bandsaw side.  I had to cut away the side of the bandsaw with my recip saw.  There is some support steel around where the motor comes through the side.  I just cut all the sheet metal away inside that square.  It was an ugly operation.  I used a file to dull the cut edges.  Whatever, it's just a tool and it works fine.

The new magnetic switch also needed a different mount to the bandsaw.  I just took a piece of scrap cherry plywood, screwed it to the bandsaw through the original holes (or maybe I tapped some new holes, I can't remember), and surface mounted my new switch to the plywood.  Works great.

All in all, I'm pretty pleased with this "adjustment" to the bandsaw.  When I get in a more permanent shop with 220 volt circuits, I'll put the original motor back on.  All the original bolt holes are still there.  But I've been able to resaw 8" wide poplar with this setup on a 20 amp circuit.  Not too bad!  And the experience with was incredible.

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