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Winner Home Grown Cutter Grinder

  • Thread starter Thread starter Bill Gruby
  • Start date Start date
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David Kirtley said:
If you are going to the trouble of building from scratch, wouldn't it be nice to add speed adjustment? Even with a grinder, you can hit those resonant frequencies and being able to tune them out is a nice feature.
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HMMMM -- I have two of these. With that option I could grind other tools that burn easily at high speed like woodworking chisels. Thank you David.

"Billy G"

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Not sure a variac will work for an induction motor (at least under light loads). If you could find a "universal" motor instead of the induction motor you have, then I think the variac would work fine. Course you could always try it. Course you could always machine a few different pulleys to change speed, but that is less of an "on the fly" thing, which is probably what you want if you are hunting for harmonics. Most designs I have seen use a single speed induction motor. For carbon steel (woodworking tools, etc). It may be easier to just make a second pulley that you can switch out as needed.

Great work as always Bill; it's looking real good. Makes me want to get going on mine again (I completed the spindle for a brooks grinder, but since then it's been sitting in a box for 2 years...).
 
DMS said:
Not sure a variac will work for an induction motor (at least under light loads). If you could find a "universal" motor instead of the induction motor you have, then I think the variac would work fine. Course you could always try it. Course you could always machine a few different pulleys to change speed, but that is less of an "on the fly" thing, which is probably what you want if you are hunting for harmonics. Most designs I have seen use a single speed induction motor. For carbon steel (woodworking tools, etc). It may be easier to just make a second pulley that you can switch out as needed.

A variac will work very poorly with an induction motor. It will work well with a "universal" motor (if it's big enough), but as most are series-wound you will have torque control, not speed control.
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That should be about the same 1/4 hp of my Dumore, which can take up to 3" wheels. What's a Tip-Lap?
 
Tip-Lap was a trade name for Lapping and Grinding Machines made in England. The Base I used was part of a Lapping Machine.

"Billy G"
 
With its shaft now in place it's time to fit this part to the work base. This may take a little doing to find the correct center height.

"Billy G"

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I now have the motor. There is nothing telling me how to wire it. The label says Volts 110/120 20.0 microfarad. They sent two 10 microfarad capacitors. These need to be wired in parallel to get 20 microfarad, correct?

"Billy G"
 
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Bill Gruby said:
I now have the motor. There is nothing telling me how to wire it. The label says Volts 110/120 20.0 microfarad. They sent two 10 microfarad capacitors. These need to be wired in parallel to get 20 microfarad, correct?

"Billy G"
Click to expand...

Correct. Post a photo of the nameplate and wiring diagram (if any). The diagram might be inside the junction box.
 
OK John, I will get that picture later today. Batteries are low. :)) Here is what I think the wiring should be for a single on/off switch. If the rotation is wrong, I just swap the two white wires from the motor Switch is a SPDT..

"Billy G"

102_0372 (800 x 531).jpg
 
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