[metlcutr55]

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used a couple times a month (for 10 yrs), the lathe began blowing fuses on start up every time. turned on already in hi rev mode day before? cant remember but surely possible. got a speed control pot (the old one had been finicky but working for a long time) put it in, now no speed control, wide open or off. turning the pot, it is off when it should come on, and on when it should be off. screw up the wiring install? quite likely but we did our best. rather than continue to fool with wiring, i liked the looks of Littlemachineshops plug play panel. but i dont need the lathe right now, and am considering a small vfd to replace the oem panel, and to be there for a likely cnc stepper retro, so i could have constant surf footage. rather than mucking up more wiring again i have competent help waiting. can i trash the grizzly spindle electronics and just use the vfd?

if i am successful with this, and get the cnc thing started, can i get more revs out of the spindle? id like to see the plastic gear train behind the headstock disappear much as possible. loss of manual use is not an issue, i can boot it into cnc mode and do 95% of what i need quickly enough. id like to see that spindle turn 10000 rpm, but could settle for 5000.

thanks in advance for your reading this and your advise !!

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[rowbare]

If you are going to spin that fast, make sure you use collets or a chuck rated for that speed. Most chucks can't handle that kind of speed and could fail catastrophically.

You also need to check what the speed rating of the bearings are. There is an article on bearing replacement here: Arc Euro Trade- Projects & Articles

bob

[109jb]

If I'm not mistaken, the 7x12 has a variable speed DC motor. A VFD is for controlling a 3-phase AC motor. Bottom line-a VFD won't work unless you change the whole motor.

You can control the stock motor under CNC control using a board from cnc4pc.com.

[metlcutr55]

thanks to both of you. im a good machinist, a fair mechanic, and a rank beginner electronics guy. because of folk like you and others who respond, im getting a feel for things, getting excited about learning more about the electronics part of the machine tools i run, also losing my fear of replacing my old mill and lathe controls and even retroing this little grizzly lathe, from the ground up as much as possible, to max my education. its all starting to make some sense, im sure there will be a flash or two and a smell of ozone, but i expected that from the start! (group)