12z Update And Status After A Year.

wrmiller

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Well, it's been a year now (doesn't seem like it...) and I apparently can't leave well enough alone, so...

I'm making changes to my mill. Again. :D

I'm finally going to install a separate control panel for the VFD courtesy of Paul at CO, and remove the fwd/rev switch and put the front panel back onto the VFD. And I'm going to redo the layout of the one-shot oiling system I put on by moving the manifold to the side of the saddle so I have only one line running from the pump to the saddle. I'll run new lines under the table to de-clutter even further.

But the big move will be the change over to ball screws on the X and Y axis. In the last year I've managed to use up all of the backlash adjustment on the X-axis nut, and instead of just replacing the nut, or designing/making a double-nut replacement like the big boys use, I've decided to just go for it and replace everything. Especially after talking to Paul and him telling me that the difference is like night and day in how the machine feels when you're operating it (they've done this conversion for other customers' manual machines). I went ahead and cheated, in that I ordered the kit from CO so I don't have to fabricate anything other than some bushings/adapters to put my handwheels on the end of the screws. Not sure if I have to do anything to re-use my X-axis power feed. We'll see.

So I've already taken the table and saddle off of the mill, and thought I'd do a close visual to see how things are wearing after a year. The ways of the table barely show any marks. Had to look real close to find any at all. The X-axis ways on the saddle show a bit more in the way of 'bright marks' (table harder than the saddle?), but they appear to be very evenly distributed. The Y-axis ways on the saddle and base barely show anything. Same for the Y-axis screw and nut. Guess we know which axis I move the most. Oh, and when I took this thing apart, the table and saddle ways were sopping wet with oil. Guess the oiler is doing it's job. :)

So stay tuned, and I'll post some comments and pics as I go through this conversion. The ball screw kit is still about a week or two from arrival (Paul was out of screws when I ordered the kit, but should have them today or Friday).
 
Damnit quit giving me ideas. I haven't even recieved my mill and im already looking to spend more on upgrades than i paid for it. Remember I have a lathe to purchase as well.

Sent from my LG-LS980 using Tapatalk
 
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Inspirational photos for you guys...

Spindle speed, forward, reverse, stop controls wired properly to the VFD allowing the VFD to control these functions. Motor wired directly to the VFD. The cable carrier worked out well to keep the cables from flopping down in the way.

This heavy gauge electrical cabinet silenced some of the noise from the VFD fan. I installed a big fan on the upper left to vent the cabinet. Those hooks came in handy on the back of the stand, you can get the track and various size/style hooks at Lowes.



The Culter Hammer spindle speed pot wasn't cheap, but its super nice, has a hydraulic feel to it and 270 degrees of rotation, you will have very fine control over spindle speed with this vs the lame VFD pot. If you go too cheap on the speed pot you will regret the decision.



I didn't want 110vac out on the controls so I picked up a 24 vdc power supply, all the controls are running 24vdc to the VFD. The relay wiring was a bit crazy, it looks like a magnetic field. As I mentioned to Bill yesterday I used 12-4 flex power cord from the VFD to the motor and 10-4 flex power cord for my 25 foot extension cord. I used 4 wire for 2 hots, neutral, and a ground. All grounds tie back to a single rail, you can see the 3 ground lugs ganged together in the pic, then off to the service panel via the extension cord big 10 gauge ground wire.
 
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Damnit quit giving me ideas. I haven't even recieved my mill and im already looking to spend more on upgrades than i paid for it. Remember I have a lathe to purchase as well.

Sent from my LG-LS980 using Tapatalk

The single, biggest bang-for-the-buck update I would recommend for this mill is the belt-drive conversion. Completely changes the characteristics of the machine.
 
Bill did you upgrade your spindle bearings when you converted to belt drive?
 
CO upgraded the bearings as part of the 3 hp/VFD upgrade.

Good point though, as this would fall to the owner to do if upgrading to the belt drive after the sale.
 
Let me know if parts need machining while your mill is out of commission for the ballscrew upgrades. Mine should be here within a couple weeks. I think...

Sent from my LG-LS980 using Tapatalk
 
Thanks Chris! :)

I will have to make a few bushings/collars to fit my hand wheels and power feed on the lathe, but according to Paul I shouldn't have to fabricate any support plates. We'll see. Paul told me yesterday that my ball screws showed up and he'll have everything boxed up and out to me in a day or two.

I'm taking the two weeks of Christmas and New Years off, so guess where I'll be spending my vacation time? :D
 
Nice! Hopefully my mill showed up in the same shipment. Still awaiting an email confirming its arrival.

Sent from my LG-LS980 using Tapatalk
 
Paul contacted me yesterday and asked if I was using my 12z with the ball screw kit as a manual machine only, and don't intend to convert to CNC in the future. Apparently, the ball screw conversion has become popular with some of the manual machine crowd, and there are some modifications that they can do to the bearing blocks to make using hand wheels much more easy. Once the mods are done though, you can't go CNC. So they are going to go ahead and make the mods and get the stuff in the mail to me next week.

It would be cool to talk to some of the other 12z owners that have done this and other mods, but don't hang out here. Is there a forum somewhere else for CO owners? Yahoo maybe?
 
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