PM932 CNC Build

You would think. Unfortunately I need an older"ish" CPU for the board I have. I may have tracked one down, I'll know in the morning. My CS experience today with Newegg was absolutely unbelievable. Enough so I will never do business with them in the future.

If you were a bit closer, I would give a you MB. I have 6 or 7 of them sitting in my computer grave yard, just about in arms reach, and I think most of them work.

Best of luck
 
If you were a bit closer, I would give a you MB. I have 6 or 7 of them sitting in my computer grave yard, just about in arms reach, and I think most of them work.

Best of luck

Thanks for the offer Jim! Me and the wife did pass through your part of the country last year. Toward the end of a 2 week road trip we drove around Mt Hood then took 211 down toward Salem. Pretty country.
 
I was able to source a used CPU from a local computer repair shop and got my system back up and running last Friday in time to get the parts I needed done by Monday. Phew!!!

Monday I started on the power drawbar parts. For some reason on these parts I ran into finish problems on the outer contours. I'm assuming it is from chip buildup in the slot. I ran these parts with a 1/4" 2-flute end mill at 10in/min at 2000rpm with 0.025" DOC. Coolant was on full. I did not employ any finishing passes. Other parts in thicker material with 3/8" and 1/2" end mills did not have this problem so I was somewhat surprised. Either I need more coolant pressure/volume, run finishing passes or both?

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I was able to source a used CPU from a local computer repair shop and got my system back up and running last Friday in time to get the parts I needed done by Monday. Phew!!!

Monday I started on the power drawbar parts. For some reason on these parts I ran into finish problems on the outer contours. I'm assuming it is from chip buildup in the slot. I ran these parts with a 1/4" 2-flute end mill at 10in/min at 2000rpm with 0.025" DOC. Coolant was on full. I did not employ any finishing passes. Other parts in thicker material with 3/8" and 1/2" end mills did not have this problem so I was somewhat surprised. Either I need more coolant pressure/volume, run finishing passes or both?

Jay

That looks like chip buildup, I have the same problem sometimes. More flood coolant might help, but my preferred method in aluminum is to use my spray mist system with WD-40, with lots of air flow to blow the chips out. A climb finish pass should pretty much eliminate the problem, I usually leave 0.015 for a full depth finish pass.
 
I was having the same finish problem at times, what I started doing was to tell d2nc my cutter was a few thousands larger than it is for the outside profiles and I'd do the offset then I would reopen the file and make another offset to do a final pass at full depth and tell d2nc the correct cutter size. It finishes the entire part at full depth in one pass just removing a few thousandths.
steve
 
Today I got air installed on the machine and the power drawbar finished. I replaced the stock drawbar with a one piece replacement drawbar for a bridgeport mill. The new drawbar is 1.25" longer so I turned a spacer to make up the difference. Air is supplied by a small compressor under the chip tray. Also added an air nozzle though I dont use these much.

Also added a selector switch and rewired the control box to have mach3 turn on the spindle and coolant or they can be run in manual mode.

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Looking good!
 
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Tonights project is a lathe stop. I tried doing the operation using tabs to hold the part but I made them too thin and I think the placement of the tabs was poor. The part came out okay but was not rigid enough for the finishing passes. I'm going to try this again using a fixture to hold the part through the holes for the magnets.


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