Maybe a good deal? Matsuura CNC mill

I own its big brother, the MC1000V-DC twin spindle. One serious piece of iron. Problem is the obsolete control. Refitting one of these guys is not an amateur project like Iggy's knee mill.

They go cheap cause hobbyists don't want them and nearly all industry buys new rather than doing a complete refit.

Karl

Karl, for my education, what is it that makes refitting them more difficult.

With the Bridgeport, indeed, I find the process straightforward, though laborious.

They are straightforward also, just ten times as much going on. So, too much labor to be cost effective. And everything is large, expensive, and hard to work on. I did just score an AMC 100A40 servo amp for the spindle at only $150 on eBay vs. 2K new. It needs a 400 volt 100 amp DC supply that you can't just cobble together with an old transformer, rectifier, and electrolytic cap. The biggest differences are in the tool changer system and the hydraulics for everything. otherwise, a mill is a mill is a mill.

Karl

At that price I would buy it if it was closer to me. The ATC would be a big selling point for me. The fact that I worked on large machines with ATCs for a number of years means I'm not scared off by the hydraulics or the perceived complexity of the ATC. Functionally it doesn't make much difference whether you're controlling pneumatics or hydraulics, it's still solenoid valves and limit switches.

Pete, if you are patient, I'm sure you can find a similar machine in your area.

I hope to be done with the refit part collecting stage for this mill by winter. I do have one system that's a total mystery to me. That's the hydraulic counter balance for the head. I'm sure it works by building to a certain pressure on the lifting cyclinders. How does the control know its balanced? What sort of sensors and etc. should I be looking for? There must be lockouts and brakes for when the hydraulics aren't up.

Figuring this dual ATC out is going to be a real challenge for me. I got no ladder logic diagrams or even electrical prints. And I've never seen it run.

Karl

Nope, it's very simple really. There are no sensors, no feedback or anything of the sort, it's noting more than a hydraulic cylinder and an adjustable relief valve. The relief valve controls the hydraulic pressure applied so it counterbalances most of the head weight.

When the servo lifts the head up, more hydraulic fluid just fills the cylinder as the pressure drops below the relief valve setting, and when the servo lowers the head, excess fluid is just dumped out the relief valve. Not really any different than the pneumatic counterbalances that just provide regulated air pressure and vent excess air when the cylinder is compressed.

Usually the servo has a magnetic brake on it that is released after the hydraulics are up and the servo drive is up.

Ok, the general idea for that style ATC goes like this:

- Spindle orients to align drive lugs on the spindle to ATC toolholder orientation

- Z axis moves to ATC height

- ATC cylinder moves ATC (still on the open pocket) in to place the ATC pocket around the tool holder

- Drawbar hydraulic cylinder releases the drawbar

- Z axis moves up to tool holder clearance height

- ATC rotates to the new tool position

- Spindle air blow it turned on to blow any chips off the new tool holder taper

- Z axis moves down to ATC height

- Spindle air blow is turned off

- Drawbar hydraulic cylinder releases, allowing the drawbar to clamp the new tool holder

- ATC retracts

That's basically it. I think some mills skip the spindle orient and use spring loaded drive lugs that click in if the toolholder slips and otherwise it doesn't matter.

Do I get a bag of apples? I love apple crisps...

...

Looks like the concepts are simple. The devil is in the details.

Sure. The problem is collecting. Ask Bob Swinney. i don't deliver.

Karl

Mostly just having the I/O for what needs to be controlled and writing the script for it. I know both EMC/EMC2 and Mach3 support scripting for such tasks, I presume your software does as well.

A few things to think about:

- No tool change without the Z axis homed

- Use timeouts on the various steps, i.e. if the ATC at spindle position limit switch isn't tripped in 3 seconds abort the sequence, something is stuck.

- Homing and indexing of the ATC varies. If you're lucky you have the type that uses a basic gearmotor and a Geneva mechanism to index it, which makes control easy. Just turn on the motor until the ATC position sensor cycles indicating the next position, or until the home sensor indicates tool pocket 1.

- The Z positioning tolerance for a tool change is reasonably loose, probably +/- 1/16" to seat the toolholder in the ATC pocket, so you should be ok with simple limit switch homing if you want to go that route vs. precision homing with limit switch and encoder index. I still recommend the encoder index method since it only requires 3 extra inputs and a bit more scripting. I also recommend using the decel switches to allow much faster homing sequences.

Who knows, one of these days I might be out that way.

Matsuura is Good Stuff.

Couldnt read the date of manufacture. And cant tell what tooling it uses. 30 or 40 taper, BNC?

Gunner

One could not be a successful Leftwinger without realizing that, in contrast to the popular conception supported by newspapers and mothers of Leftwingers, a goodly number of Leftwingers are not only narrow-minded and dull, but also just stupid. Gunner Asch

Pretty sure that's a BT30 machine.

No CRT on the control puts it in the late 80s or earlier. A guy that really knows Matsuura can tell you when they switched from blue to the big red machine. Then they switched back to blue again.

Karl

Ah! Thanks for the heads up. I dont run across many of them here on the Left Coast.

Gunner

One could not be a successful Leftwinger without realizing that, in contrast to the popular conception supported by newspapers and mothers of Leftwingers, a goodly number of Leftwingers are not only narrow-minded and dull, but also just stupid. Gunner Asch

Most all cnc machines after 1981 had CRT's. That control sorta looks like a Fanuc 5 which was the predecessor to the Fanuc 6 but without the crt and some functions. The control itself doesn't look very worn around the knobs but the pictures aren't too clear either.

John

That you Sam?