PM-728 Setup for sale

Moderator: cnckeith

Post Reply
jpmsteadi
Posts: 62
Joined: Fri Feb 19, 2021 5:51 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: E415F6F1121A-1204204111
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No

PM-728 Setup for sale

Post by jpmsteadi »

Hi all! 6 months after getting a bigger cnc machine (Sharp 2412, a real big boy) I am coming to realization that I have not used my converted mill at all.

I need the garage space, so I am listing the PM728 conversion.

You can check out videos and info on the conversion here: https://centroidcncforum.com/viewtopic.php?f=57&t=5650

To summarize:

-Precision Matthews 728VT
-Ultra precision ball screw kit
-Centroid Acorn of course!
-Clearpath Nema 34 Motors on all 4 axis. The XYA are the SDHP I found on ebay. 1.4kw each. Very fast rapids for a bench machine! The z is now a larger SDSK.
- I have added in some upgrades along the way and so the conversion isn't the prettiest one and I would certainly make it cleaner if I did it again, but it works very well. The spindle upgrade is fantastic. SO much more power.

The good:
-high power clearpath servo motors give accurate and fast positioning (300ipm rapids)
-converted spindle is a 2HP 6000 rpm spindle. HUGE improvement over the stock setup
-custom power drawbar makes changing tools easy
-has a 4th axis - a converted grizzly rotary table I had laying around. Works okay, but not super rigid. Take light cuts.
-comes with a bunch of tormach TTS tooling (19 tool holders)
- will include a 4” vise (not pictured) and some end mills to get started
- has rigid tapping setup.
- uses a fogbuster minimum quantity lubricant setup for coolant.
-comes with computer setup.
-will include cabinet for additional cost

The not so good:
- the enclosure works, but it ain’t pretty. Was built during the height of Covid with scrap wood I had laying around the garage. Should 100% be updated.
-the last job I did on it the rear chip flap got caught and ripped. Should be replaced.

I like being completely transparent with selling stuff:
I am not a professional cnc machine builder and I learned a TON during this conversion. It works well, but I would make slightly different choices next time. I am happy to chat with a potential buyer about the pluses and minuses of not only this machine but also a conversion vs a tormach or Syil or something.

I have about 11k into the mill and conversion, but completely understand that it’s not worth that on the used market. It’s taking up space. Make a reasonable offer.

I’m happy to show people the mill or send videos/sample parts. Also willing to help install/do the initial setup if you are close.
Post Reply