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CNC knee mill & controls

kubeski

Plastic
Joined
Oct 17, 2012
Location
Cambridge MA
We're looking for a 3-axis CNC knee mill for our R&D/prototype shop. There will be many users and for most of them who have limited training we just need a dependable manual Bridgeport. But for higherup reasons, it has to be new, and it has to be 3-axis CNC factory installed.

It does not have to stand in for a modern VMC. It will complement the Haas OM-2 we already have. The OM-2 is the only "serious" VMC we could get into our upstairs office-building space. Haas knows this, and charges accordingly. We have some years of CNC experience on our team, but all with Haas controls.

We've had a look at a Trak K3, an easy choice: popular, good support, cheap. Two things didn't impress:

  • SMX control seemed very awkward with a limited softkey interface. I know that's the style, but, for example, two button presses to reverse jog direction? Not evident anybody really thought things through.
  • Electronic quill feed. The zero feedback is disorienting and seems accident prone.
It really made me wish we could size up a competitive mill in person, but only SWI has a Boston area showroom.

Some questions:

  • Does anybody make a CNC'd quill with real mechanical manual feed as most do for X and Y?
  • Is there anybody here in greater Boston who'd host a brief visit for us to see a control or mill they think we ought to consider?
On paper, the most interesting alternative was the Lagun Millmatic. Both for the iron, which seems to have a small satisfied following, and the Fagor 8055 control they sell as an unusually good cross between walk-up usability and capability. Iron production recently moved to Taiwan from Spain, which may or may not mean anything. As for the Fagor, on YouTube anyway, it looks a lot more sophisticated, but only a little less muddled, than the Trak SMX.

Thanks for your thoughts
 
We're looking for a 3-axis CNC knee mill for our R&D/prototype shop. There will be many users and for most of them who have limited training we just need a dependable manual Bridgeport. But for higherup reasons, it has to be new, and it has to be 3-axis CNC factory installed.

It does not have to stand in for a modern VMC. It will complement the Haas OM-2 we already have. The OM-2 is the only "serious" VMC we could get into our upstairs office-building space. Haas knows this, and charges accordingly. We have some years of CNC experience on our team, but all with Haas controls.

We've had a look at a Trak K3, an easy choice: popular, good support, cheap. Two things didn't impress:

  • SMX control seemed very awkward with a limited softkey interface. I know that's the style, but, for example, two button presses to reverse jog direction? Not evident anybody really thought things through.
  • Electronic quill feed. The zero feedback is disorienting and seems accident prone.
It really made me wish we could size up a competitive mill in person, but only SWI has a Boston area showroom.

Some questions:

  • Does anybody make a CNC'd quill with real mechanical manual feed as most do for X and Y?
  • Is there anybody here in greater Boston who'd host a brief visit for us to see a control or mill they think we ought to consider?
On paper, the most interesting alternative was the Lagun Millmatic. Both for the iron, which seems to have a small satisfied following, and the Fagor 8055 control they sell as an unusually good cross between walk-up usability and capability. Iron production recently moved to Taiwan from Spain, which may or may not mean anything. As for the Fagor, on YouTube anyway, it looks a lot more sophisticated, but only a little less muddled, than the Trak SMX.

Thanks for your thoughts
.
thats why 2 axis cnc like Prototrak knee miil are popular. can use as a manual machine. can drill manually and feel as oppose to electronic jog mode
.
less crashes happen on a 2 axis mill as Z axis moves are manually done. thus why starting out on a 2 axis cnc is popular for training manual machinist or new people
.
i always liked Protoraks. comparing to a 3 axis cnc thats more than 2x the cost and has more features is not a fair comparison. Prototraks are better at programming at the control conversationally. obvious there are advantages and disadvantages
 
I'm not sure if it's still made, but Bridgeport used to make 3 axis knee mills with an unlockable quill. For a given program, you have to choose whether the quill is CNC or manual, and there's nothing in between. But it's fairly simple to switch back after each program finishes. I ran that machine off of G codes, so I have no idea what their conversational controls are like. Bridgeport seems to regularly scrap their controls and start from scratch, so I'm sure some years would be better than others.

They're a bit bigger, but I think the Trak bed mills might be better for your purposes. I ran one of these for a few years:
TRAK DPM SX3P - Southwestern Industries, Inc.

The quill is completely manual, but the whole head goes up and down like a normal bed mill. The X and Y handles are manual, but I'd recommend the electronic upgrade. That gives you the option of stepping through your programs as quickly or slowly as you want, by turning the handles. You can even run sections of a program backward, by turning the handle backward. It's incredibly helpful for teaching someone to program. Being a bed mill, it's not quite as versatile as a knee mill, but it's much more solid. And you don't need to jump through any hoops to go back and forth between full manual, and full CNC. (switching to 2 axis CNC takes a few keystrokes, though) The conversational code is pretty good. It was a bit buggy running G codes, especially on canned cycles. But that was years ago, so they've hopefully fixed that by now.

Kent, Victor, and, I believe, Hurco all used to make similar bed mills. I haven't checked lately, though. I don't know of anyone other than Bridgeport who made a knee mill that can run as both 2 and 3 axis. If anyone else does, I'd guess Kent.
 
Also the prototrak 2.5 axis can be opened in two axis mode, my old MX3 is 2.5 axis but will also run 2 axis if needed, so those who only know how to use the 2 axis and manual quill can use the 2 axis mode. And those more farmiliar can open the program im 3 axis mode.
 
Wow,
Can't imagine anyone WANTING a CNC knee mill! Bed mill all the way. Manual Quill and lots of Z axis, what's not to love? SW makes one so do several other people. We have a Servo 5000. Kind of sucky CNC control but the iron is quite good It runs on Windows so we have a CAM program right on the control. 1989 machine with 2005 control upgrade and 100 hrs of actual run time, Full fourth axis, 23 Nikken Cat 40 tool holders, $6500. Hard to say no!
 
We have been using Lillian Knee mills with an Accurite MILLPWR controller for a while and they are great. We purchased a lillian 5vh with a FAGOR control and it is a pain in the ass to program. No one in the shop will run it. The MILLPWR conversational programming is really easy to learn and when the part gets complicated you can resort to DXF files. The control is easy to use and most guys pick it up in a couple days. Just my 2 cents

MILLPWR G2 Control Systems :: Acu-Rite
 
We have used a Sharp LMV knee mill w/ Acutite Millpoweer 3 axis control for years. Very accurate, easy to use. It does disconnect the quill for 2 axis work. For more complicated work, or full 3 axis work,we feed it with G-code. Usually faster to set up and run then a VMC, for small runs or one offs.
 
I find the Acu-Rite Millpwr control so much easier than the Prototrac or the Fagor, especially for R & D and occasional users. It takes seconds to go from CNC to manual mode with just the simple turn of a hand wheel to disengage the quill from the servo drive. The Sharp mill with box ways is built in Taiwan and is very rugged and dependable. I can take you to MIT nearby to see the control in use.
 
Thanks for all the comments. Sounds like there is not much love for the Fagor control, and that a disengagable quill (no need for electronic handwheel) is not a unicorn, at least Sharp and Lagun (I called them since I posted) have them.

Knee mills are out of fashion but we thought it would be a bit more familiar for the folks with basic skills, and the few of us likely to be the more frequent users prefer that setup as well. It's also a little easier to move the machine, to fixture and cut big awkward parts, and to see your work because of the open table.

I tried once to contact CNC Automation, no answer, will try again.

Pamco I will send a PM, we'd love to have a look at another shop especially if it's as close as MIT.

I find the Acu-Rite Millpwr control so much easier than the Prototrac or the Fagor, especially for R & D and occasional users. It takes seconds to go from CNC to manual mode with just the simple turn of a hand wheel to disengage the quill from the servo drive. The Sharp mill with box ways is built in Taiwan and is very rugged and dependable. I can take you to MIT nearby to see the control in use.
 
We're looking for a 3-axis CNC knee mill for our R&D/prototype shop. There will be many users and for most of them who have limited training we just need a dependable manual Bridgeport. But for higherup reasons, it has to be new, and it has to be 3-axis CNC factory installed.

It does not have to stand in for a modern VMC. It will complement the Haas OM-2 we already have. The OM-2 is the only "serious" VMC we could get into our upstairs office-building space. Haas knows this, and charges accordingly. We have some years of CNC experience on our team, but all with Haas controls.

We've had a look at a Trak K3, an easy choice: popular, good support, cheap. Two things didn't impress:

  • SMX control seemed very awkward with a limited softkey interface. I know that's the style, but, for example, two button presses to reverse jog direction? Not evident anybody really thought things through.
  • Electronic quill feed. The zero feedback is disorienting and seems accident prone.
It really made me wish we could size up a competitive mill in person, but only SWI has a Boston area showroom.

Some questions:

  • Does anybody make a CNC'd quill with real mechanical manual feed as most do for X and Y?
  • Is there anybody here in greater Boston who'd host a brief visit for us to see a control or mill they think we ought to consider?
On paper, the most interesting alternative was the Lagun Millmatic. Both for the iron, which seems to have a small satisfied following, and the Fagor 8055 control they sell as an unusually good cross between walk-up usability and capability. Iron production recently moved to Taiwan from Spain, which may or may not mean anything. As for the Fagor, on YouTube anyway, it looks a lot more sophisticated, but only a little less muddled, than the Trak SMX.

Thanks for your thoughts

I have an SMX bed mill and would not want to go without it, Not sure what you mean about the zero Feed back thing but it is easy to tell if you are + or - when in jog by looking at the screen, the display clearly tells you if you are in + or - in the jog feed rate box.

We regularly program off line in Master Cam and run complex operations in this machine when our machining centers are busy. Not having a tool changer is the only draw back to this. I rarely program at the control for anything more complex than drilling or simple one step routines but it can easily be done once you are familiar with the control.

My shop was build on the back of this machine, we now have four machining centers three CNC lathes and not one quiet day :)

We also have a 1630 Trak CNC lathe. The mill was the first machine I bought for this shop. It combines all the features and flexibility of a manual machine and a full blown 3 axis CNC.

You are welcome to contact me I have some strong relationships with MIT and have consulted and set up machine shops for more than one MIT start up company.

I would gladly help you out in any way I can.

Make Chips Boys !

Ron
 








 
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