BP Series 2 Special. Convert to CNC via older Millpwr kit???

I currently have a series 2 special with 2 axis dro and x-axis power feed. I really never planned on a cnc knee mill, but my place of work had a charity auction and i purchased what I was told was a complete running kit that was removed from a regular series 2 machine to upgrade to a newer kit. From what i was told the only known issue was that the start button on the control was somewhat finicky. I didnt realize this was being auctioned off until it was almost over and pulled the trigger with out much research. I am looking for some input.
1. I think this should be a direct bolt on for my machine since the series 2 and series 2 special are basically the same from the column down. Is it a direct bolt on?
2. From the pictures attached, did i get all the major components that i couldnt easily and cheaply replace?
3. I wasnt really in the market for a cnc. Is this fairly user freindly? I haven't touch a cnc control in 15 years.
4. Finally, what is this worth (assuming its complete and works)? Hoping i didnt over spend even if it was for charity...

Looks like you should have everything, assuming that the scales are in the long boxes. The only thing you might need is a different mounting kit for the Z axis scale. And it all depends on what you think "cheaply" is. The new pendant (front plate for the keys) is $510.

Ah, AC brushless system... Didnt see the square motors until that 2nd to last picture. Personally I prefer the DC brush motors, but thats just a personal preference. And I am not sure if Acu-Rite is even fixing the old AC brushless motors... However, I would hold off for another month or two before you decide to do anything with the motors (if they dont work, that is).

You should be able to use the kit to put it on with what you have.

The control is ridiculously user friendly. It is all conversational code. In the back of your manual it has a sample program to write and get to know the controller a little more.

As far as worth... a new 2 axis kit for a Series II/Series II Special is $18,059/$17,889. But this is the old MP2 not the G2 and they currently dont sell the AC brushless motors with a G2. So... I mean I would guess if you got this for under $10k you might say its a good deal. But why was it removed from the machine? Even if just to put a new kit on it, why?


Jon
H&W Machine Repair

Well I didn't pay near $10k for it, so i feel better about that.

As for the reason for removal, there are 2 series II machines side by side in our tool room. There was $ in the budget this year to upgrade the older one. It had an old millpwr kit(had the large power cabinet on the back). It had the screen getting dim and fuzzy, among a few other small issues, but it did work too. Decision was made to refurb both at the same time. New kits, vfd controlled direct drive motors, tore down, re-scraped, and painted.(I bought both motors too. One was motor was recently rebuilt, but i have no use for them.) I talked to the guy that did the refurbs, and he said the only known issue with the one i bought, other than the finicky start button, was one of the servo wire connectors was broken and was being held in place with zip ties and tape...

I do have another question about this. There is a spot on the back of the controller listed for z servo. Is this upgradable to 3 axis?

Not for a Series II, but you could do it on your Series II Special.

However, the next thing you are gonna run into is the AC brushless motors. I am not sure if an AC brushless and DC brush motors are compatible in the same retrofit kit.

The 3rd axis kit is like $6,921 for the parts. You wont need to unlock anything on the console, just download the software from Acu-Rite's website.

Jon
H&W Machine Repair

Where would i find a millpwr installation/ parts books for the series 2 special?

breymeyerfam said:

1. I think this should be a direct bolt on for my machine since the series 2 and series 2 special are basically the same from the column down. Is it a direct bolt on?

Click to expand...

You have that backwards!
The machines are the same from the column up!

IIRC, the lead screws are not the same between the two machines either?

You are going to have to adapt the motors to your mill and replace the ball screws? The only thing you can reuse are the motors and control?

Get a price on replacement ball screws before you go any further, you may not want to invest that much into this project?

Kevin

bsg said:

You have that backwards!
The machines are the same from the column up!

IIRC, the lead screws are not the same between the two machines either?

You are going to have to adapt the motors to your mill and replace the ball screws? The only thing you can reuse are the motors and control?

Get a price on replacement ball screws before you go any further, you may not want to invest that much into this project?

Kevin

Click to expand...

This is my mill(11x58). Really old pic from the day I got it home, but representative of what i have. Like I said earlier, with the kit removed from a 4hp series 2, I was thinking x & y axis should be bolt right on to mine, but I sure could be wrong.

Question: Before I take the time to swap screws in my machine. I want to power this thing up to validate it does work. Do i have to have all the scales and servos hooked up to power it up?

The Series II Special is a Series II with a Series I ram knuckle and head. The difference between a MillPWR on a Series II and a Series II special is the head section. You Cannot use a 3 axis kit on a Series II, but the 2 axis side is the same. (I have installed MillPWR kits on both).

The only way to truly test the system is to have it installed and tuned on your machine.

Jon
H&W Machine Repair

Im going to replace the ball screw end bearings. With the parts i have here, there seems to be two different bearings. Both are the same size of 20x47x14. Without a parts list im just guessing, but it looks like there should be qty 4 of 7204 and qty 1 of 6204. This sound right?

Yes theyre 7204's, Acu-Rite uses Fafnir and NSK bearings. 2 per axis.

The 6204 goes on the handle side of it.

Jon
H&W Machine Repair

I got the table off my mill today. Glad i did too. 2 of the oilers for the table wasnt getting much oil. Got them cleaned out and getting oil now.

Everything seems pretty straight forward with the conversion but the y axis ball screw nut oil line. The acme nut is fed through the top of the saddle down through the yoke right into the nut. The supplied yoke doesnt have an oil feed hole through it for a feed line to the ball screw. Without getting crafty, im assuming just running a hose from the oil pump under the knee to the ball nut is the easiest way?

Well it looks like I have only one of the table end plates. Are these available from acu-rite? If not, it looks fairly easy to copy.

It should have just the motor mount on the other side. I will look at the kits tomorrow and see if you are supposed to have two. I will let you know tomorrow.

Jon