Shopsmith Forums

Here's a question which I expect will not only receive many resounding NO! answers to : Can you use a router speed controller with your Shopsmith Mark V?

NO!

Router speed controls only work with motors having brushes. No brushes in Shopsmith Mark5 ( or 505,510,520, VII or 7) motors.

Answer above is correct.



For AC motors you would need a VFD (variable frequency drive) but these really only work with 3 phase motors. Any motor with a capacitor (like the shopsmith) won't work because the start circuit would turn back on as the speed slows and fubar the whole process.

I have thought about offering VFD kits for the shopsmith. That would replace the standard motor with a 3 phase reversible motor, eliminate the speed control, replace the sheave system with standard pulleys (no more oiling!), and create a custom VFD control panel that takes the place of the speed control dial on the front. Once I convince my wife to get me a good milling machine, I'll make a prototype. (Sadly years away I think )

joshh wrote:Answer above is correct.



For AC motors you would need a VFD (variable frequency drive) but these really only work with 3 phase motors. Any motor with a capacitor (like the shopsmith) won't work because the start circuit would turn back on as the speed slows and fubar the whole process.

I have thought about offering VFD kits for the shopsmith. That would replace the standard motor with a 3 phase reversible motor, eliminate the speed control, replace the sheave system with standard pulleys (no more oiling!), and create a custom VFD control panel that takes the place of the speed control dial on the front. Once I convince my wife to get me a good milling machine, I'll make a prototype. (Sadly years away I think )

Interesting 'hypothesis'.

Lotsa things to over come!

Whatsa milling machine got to do with it?



P.S. any 3ϕ motor is reversible!

JPG40504 wrote:Whatsa milling machine got to do with it?

The goal is to mount the VFD controller where the speed control dial is. I plan on milling a mount that will fill the space and anchor the VFD to the shopsmith in a way that will stand up to gorillas mashing on the control pad Think "poor man's powerpro"

I was thinking aluminum would look nice. I guess I would need a metal lathe also for the outer ring...or at least a rotary vice.

JPG40504 wrote: P.S. any 3&#981]

Yep, and all the VFD controllers I have seen take advantage of that fact.

joshh wrote:The goal is to mount the VFD controller where the speed control dial is. I plan on milling a mount that will fill the space and anchor the VFD to the shopsmith in a way that will stand up to gorillas mashing on the control pad Think "poor man's powerpro"

I was thinking aluminum would look nice. I guess I would need a metal lathe also for the outer ring...or at least a rotary vice.



Yep, and all the VFD controllers I have seen take advantage of that fact.

A couple months back my nephew showed me one of those 3D printers. The plastic used to make the piece was quite strong. Could something like that be used in lieu of what you would make with a milling machine?

Not to throw a wrench into your plans to acquire a milling machine, but maybe if you start making the souped up SSs using the pieces designed and built with the 3D printer you could use the profits to buy a BIGGER milling machine. I understand that some of those that have a printer are willing to do cheap prototyping.

joshh wrote:The goal is to mount the VFD controller where the speed control dial is. I plan on milling a mount that will fill the space and anchor the VFD to the shopsmith in a way that will stand up to gorillas mashing on the control pad Think "poor man's powerpro"

I was thinking aluminum would look nice. I guess I would need a metal lathe also for the outer ring...or at least a rotary vice.



Yep, and all the VFD controllers I have seen take advantage of that fact.

Where ya gonna get a motor capable of a 40:1 frequency/speed range?

Come on Guys! Please remember the mechanics inside the Mark V. There just is NO device mounted on the headstock that will change the speed more than the sheaves we already have. Unless you are going to re-engineer the entire works.

I know you are thinking electronically - But What can that change? If you change the RPM of the motor, perhaps you can slow down the spindle, but will you lose power?

Please remember that the Mark V motor ALWAYS maintains at a given RPM, regardless of the spindle speed. In a normal unit, the motor speed doesn't change. The sheaves change and this changes the configuration of the pulleys - therefore the spindle speed.

charlese wrote:Come on Guys! Please remember the mechanics inside the Mark V. There just is NO device mounted on the headstock that will change the speed more than the sheaves we already have. Unless you are going to re-engineer the entire works.

I know you are thinking electronically - But What can that change? If you change the RPM of the motor, perhaps you can slow down the spindle, but will you lose power?

Please remember that the Mark V motor ALWAYS maintains at a given RPM, regardless of the spindle speed. In a normal unit, the motor speed doesn't change. The sheaves change and this changes the configuration of the pulleys - therefore the spindle speed.

Ahem! You gots one!:D

JPG40504 wrote:Ahem! You gots one!:D

Yep! Caught my poor English writing skills. There should have been a comma after the word have and in front of unless.

So I'll repeat those statements using correct punctuation:

"There just is NO device mounted on the headstock that will change the speed more than the sheaves we already have, unless you are going to re-engineer the entire works."