Grizzly G0733 LATHE WARNING

[mike calabrese]

Hey gang
new here and woodworking again after about 20 years printing tee shirts.

An interesting thing happened with my new Grizzly G0733 lathe I will share for what it is worth.
Note I am not much on electronics but have kind of an engineering background.

I just built a 17 inch diameter donut chuck using 3/4 birch ply, (it has a lot of inertia once spinning). working on a couple larger diameter bowls I used the speed change knob to shut down the spindle.
My heart stopped when I tried to restart the spindle........ the motor was dead, nothing going on not even digital readout on the headstock.
I thought I fried something on a brand new lathe.

Fortunately after about 3 minutes I was able to restart normally and all is good again.
I suspect what happened is some kind of feed back electrically from the rotating spindle back into the inverter or some of the electronics???????
What i noticed was on spin down (using the speed knob) there seemed to be a drag on the spindle speed and it slowed kind of quickly to a stop.
Conversely when cutting the power either with the forward / reverse switch or start / stop buttons the roll down to stop took considerably longer and was a smooth roll down transition.

So what I am suggesting / guessing, and will do from now on is cut the power when I have a high inertia load and possibly save the inverter or some other electronic component.

calabrese55

[Kevin Jenness]

I think that is common on electronic speed controls with large loads. When you decelerate rapidly using the speed control or when the inverter brakes a very large load at its normal deceleration rate the inverter shuts off and needs resetting and the workpiece coasts to a stop. Some lathes like Oneway have adjustable braking speeds and optional braking resistors to deal with this situation.

[mike calabrese]

Kevin,
Thank you for the information. That all makes sense based on the situation I had.
Thanks again for your time and knowledge it helped a bunch to support the hope I didn't fry anything.
mike c

[Roger Chandler]

Decelerate with your speed control knob slowly with that much inertia on the spindle. You over ran the inverters program for deceleration. Always use the speed knob instead of the stop button or fwd/rev switch…..the inverter is programmed for that sequence, and it will serve to protect the inverter.

[mike calabrese]

Thanks Roger
I will take all the help I can get here. Returning to woodworking after 20 years on other adventures kind of leaves me starting back with a Fred Flintstone knowledge base.
Throttling down SLOWLY with speed knob does seem to work woth a smooth transition.
Thanks again for your time and knowledge.
mike c

[Reed Gray]

This might also be from turning in the high speed range. Generally bowls are turned in slow speed range, and spindles in high speed range.

robo hippy