[chipslinger69]

I conducted the break in sequence on my new mill the other day and I have a question or two for other owners. First off, the mill now has over 1 hour run time. During break in the bearings sounded great. No loud noises what so ever. They were actually quite and smooth in high, low and reverse. The problem or question, the highest rpm it will obtain in low forward is 985. The highest rpm in high forward is 1935 and the highest in high reverse is 985. These numbers seem very low to me as they are no where near the advertised rpm ranges. Shouldn't I already be seeing higher rpms or does anyone feel they will rise as the bearings get more time on them? During the break in the upper and lower bearings never went over 103 degrees as per my thermometer and the motor temp at the brushes never went over 130. I don't know if or when they went to a different motor on these mills but the manufacturing date on my mill is 06-12 and the motor is a 95ZYT08, DC110V 4100r/min CCW, NO: 120504. Should I attempt the pot adjustments on the control board? Any info would be greatly appreciated.

[hoss2006]

They purposely detuned the controllers to prolong the life of the motor, it's still more rpm than an sx3.
I wouldn't recommend over tuning unless you have a replacement on hand, the gain isn't that great or worth the risk.
Get an upgrade motor and controller anyway to get much more out of the mill and play it safe with the stock ones.
Hoss

[chipslinger69]

Thanks for the reply Hoss. That's kind of what I was thinking. I guess those rpms will suit me fine for now. Now to completely strip it down, clean, inspect, reassemble, oil and dial it in.

[Fastest1]

I just barely get over 2000. Maybe 2035. No mods, motor broken in for a few hours.

[hoss2006]

Yeah the normal used to be 2250 before the bad motors started making an appearance but
at least that's a much rarer occurrence now.
Hoss

[chipslinger69]

Yeah, I would rather it only get 1935 than to be changing out motors and controllers. I'm glad I tore it down. There was gritty grease on ever part that was not accessible on the initial clean up. Plus, as of now I have found that the column gib is twisted at the bottom causing it to not make full contact with the column. I'm sure I can take the twist out of it with just a little persuasion. Then onto the table and base to see what kind of secrets they hold.

[Fastest1]

I was mistaken, I just got 2275, it does help to turn up the pot!

[chipslinger69]

Is it just me or does something not look right in this pic?

[Fastest1]

Wtf is that? The base? Where is the opening for the Y ball mount? What am I seeing? I thought I had seen mine from every angle!

[Fastest1]

Damn phone pics are too small. That is the Z carriage? It does seem odd. I wi have to go back and look at my pics but I don't remember mine looking like that.

[109jb]

He's talking about the blued surface and the few small contact points.

[Fastest1]

Thanks 109, I saw that but couldn't tell if it was bluing due to the pic being so small on my phone.

[chipslinger69]

Yeah, I didn't even waste my time with lapping. I went straight for the mill tooth file. Running it the length of the carriage focusing on the high spots. Then I finished it off with some 1000 grit lapping compound. Smooth as butter now. And most importantly, it's flat.