Continuously Variable Speed Band Saw

[Texaswally]

Would it be of any real advantage in woodworking to convert a band saw to continuously variable speed? This would be fairly easy to do, just change the motor to 3-phase and power it with a VFD. My thoughts are the cost wouldn't justify the change and if it was such a good idea, they would be available commercially.

Edited November 24, 2017 by Ron Dudelston
tags added

[Gene Howe]

They are available. Shopsmith. Pretty small though. 10" throat and, 6" depth of cut. 

[Stick486]

put a Love Joy Variable Speed Pulley on it instead...

think VS lathes...

[Fred W. Hargis Jr]

I keep thinking about it, and couldn't come up with a reason for the VS. What got me to that point was having a 3 phase motor on hand that could have been used on the BS, the VS is just there for the ride. In the end I didn't do it (the motor is on my lathe). (Plane Sawn">PS, the plan was to switch the VFD back and forth between lathe and bandsaw...the connections between the tools and the VFD are just on 4 prong plugs/receptacles.

[Texaswally]

I just wonder if band saw blades are designed to work in a fairly small range of speeds. Too slow and they could burn the wood, and too fast, clog the gullets causing all kind of troubles.

[Dadio]

I would convert over the drill press first.

I have been thinking of doing that , anyone know what the ballpark cost would be?

Herb

[Stick486]

hurt yur brain...

[Texaswally]

1 hour ago, Dadio said:

I would convert over the drill press first.

I have been thinking of doing that , anyone know what the ballpark cost would be?

Herb

I bought a Grizzly G7948 - 12 Speed 20" Floor Drill Press last winter and converted it to variable speed using an eBay 1.5 Hp 3 phase motor and a Teco FM-50 2 hp VFD. Cost was about $350 for both plus $125 for machine shop work to bore out the step pulley to fit new motor. for a total of 500 bux. Gives a range of 100-3500 RPM. Needed a HF link belt to stop the vibrations.More info later.

Edited February 10, 2017 by Texaswally

[Al B]

Variable speed may be an advantage, but I can't say that I've ever felt a need for it.

[Dadio]

3 hours ago, Texaswally said:

I bought a Grizzly G7948 - 12 Speed 20" Floor Drill Press last winter and converted it to variable speed using an eBay 1.5 Hp 3 phase motor and a Teco FM-50 2 hp VFD. Cost was about $350 for both plus $125 for machine shop work to bore out the step pulley to fit new motor. for a total of 500 bux. Gives a range of 100-3500 RPM. Needed a HF link belt to stop the vibrations.More info later.

Thanks Wally, I will do some checking into that. Maybe you could do a thread on that with some pictures and explain about any performance issues good or bad. One thing I am concerned about is if the slower speeds loose power.

Herb

[Fred W. Hargis Jr]

They do. The torque diminishes at the lower frequencies. On my lathe I can usually operate down to about 40 hz. Lower than that the motor (a 1.5 HP Baldor) doesn't have enough power to do much. The lathe has a 8 step pulley set up, so I change the belt around. Someone once explained to me the technical details of this and it was stored away in some unreachable corner of my brain (which should be very crowded, I would think).

[Gene Howe]

I can vary the speed on the Shopsmith but, never do. Haven't run into a situation that made it necessary, yet. 

[HandyDan]

I would go for the VS drill press first.  I like that idea.