Mechtronics-Dyna EM3116 cnc knee mill

[shoptalk00]

CNC knee mill people,

I am looking at buying a mid/late-1990's DYNA EM3116 CNC Knee Mill, 3 Axis with Dyna 4M PC-III Control. Anyone have any knowledge or experience with these machines? What are the controls like for programming on these machines? I was kinda wondering about the overall construction of the servo system. The servo drive motors seem to be very small compared to most others. Comments please...

Thank you

[Caprirs]

The machine is a typical generic Bridgeport copy.

Control is identical to the one used on Dyna's full size vertical machining centers. If you could add an encoder and precise speed control to the spindle, the machine would be able to rigid tap just like the big machines.

Control is PC based running MS-DOS 6.xx with an IDE hard drive. Going from memory, the rapids are 300ipm and max cutting feed is 200ipm. Axis servos use belts and timing pulleys at either 3:1 or 4:1 ratio. Standard R8 spindle with a power draw bar. Travels are X31" and Y16". Can be used as a manual mill with fancy DRO by pressing a single button on the control panel.

Uses standard G/M codes with some conversational codes built in. 3.5" floppy drive and RS232 port.

[shoptalk00]

Hello Caprirs,

Thanks for the reply back. I have some other questions regarding this Dyna mill. Little back ground about myself, I'm an engineer with a daytime job and have a small machining and welding shop at my house. I have some ideas and designs I would like to market some day, thus the reason for needing to upgrade to a cnc unit. I have the opportunity to buy this Dyna mill for about the going price of a standard manual knee mill in my area.

My questions are:

Can I get/buy replacement parts (mechanical and electrical) for this machine?

Why are the servo motors so small on this machine, does this effect motor performance output (torque/speed/ref)?

Can this machine be ran from a conversational mode only and is it user-friendly (I don't have any offline cad/cam systems right now)?

Can I use any cad/cam software with the Dyna controls? Any post processing requirements?

Both the power drawbar unit and jog handwheel controller are missing. Can I adapt an "after-market" power drawbar unit and get/buy a jog handwheel controller?

I plan to use this machine for proto-typing and light-to-moderate production, cutting a wide range of materials (mostly steel and alum) any concerns or other comments?

Thank you for your time...

[Caprirs]

Can I get/buy replacement parts (mechanical and electrical) for this machine?

Some part are available. When the 3116 was initially introduced, the control had an industrial PC made by Winsys (I think) which was 486-based and had a monochrome LCD. Later machines were made with off-the-shelf Shuttle main boards using Pentium CPUs and a whopping 16MB of RAM. Replacement of the PC parts is limited by the ability to interface with the video card and communications cables to the Big Board in the back power cabinet.

Why are the servo motors so small on this machine, does this effect motor performance output (torque/speed/ref)?

Not sure what you mean by small? They will move the table at 300ipm rapids. Are you concerned about stalling the motors while cutting? Any size servo can be stalled and without knowing your full cutting conditions, there's no way to predict if these are strong enough.

Can this machine be ran from a conversational mode only and is it user-friendly (I don't have any offline cad/cam systems right now)?

There is a semi-conversational mode but it still uses G-codes. In the program edit screen, all supported G/M codes are listed on the right side. Selecting one of those codes will bring up a rudimentary pop-up that graphically displays what the G code will do. There are built in codes for rectangular & circular pockets, bolt hole circle drilling, rectangular arrays, etc. In my experience, conversational controls are handy when first learning but become a real impediment and hassle as the user gets more comfortable with the machine.

Can I use any cad/cam software with the Dyna controls? Any post processing requirements?

Any CAD/CAM can be used to create tool paths. CAD/CAM companies write their own post processors to take the tool paths and convert them to the motion code specific to each machine. Since the 3116 uses standard G/M codes, nearly any CAD/CAM will work. No matter which software used, a little hand editing is almost always necessary. The hand editing is typically minimal and specific to the machine/machinist/shop. For instance, I use an old version of GibbsCAM and subprograms are called by M98 Nxxxx but my machines need the format to be M98 Hxxxx. Thus, after creating the tool paths and after posting the code to a text file, I open the text file with Notepad and do a find/replace to change the M98 lines. The text file is then sent via RS232 to the mill and stored in the machine memory for execution.

Post processors are proprietary to each CAD/CAM company and wirtten to convert the proprietary tool paths into the properly formatted motion code for the machine. For example, a Mastercam post processor cannot be used to convert BobCAD tool paths. The post processor handles the specific codes for each move along with all the fussy stuff like whether the machine will accept M3 or must use M03 to turn on the spindle. The Dyna is pretty easy and not too picky.

Both the power drawbar unit and jog handwheel controller are missing. Can I adapt an "after-market" power drawbar unit and get/buy a jog handwheel controller?

I think any power draw bar can be adapted but do not know that for sure. The handwheel might have to come from Dyna and they should be able to get one for you. No idea on price.

I plan to use this machine for proto-typing and light-to-moderate production, cutting a wide range of materials (mostly steel and alum) any concerns or other comments?

If you get much use out of it, you'll probably want to get a full size machining center with tool changer, flood coolant, rigid tapping, and full enclosure pretty soon. The less you have to tend to the machine changing tools and cleaning up, the more time you can spend doing other things.

[shoptalk00]

This machine has the Pentium CPU board inside the operator control panel (I think this machine is a 1997-1998 model). The servo motors on this machine measure around 2" in dia and 4" long and are directly belt driven to their axis. This motor size seemed very small in size compared to all the other cnc knee mills (same size and set-up) I have looked at in the past. Just something that caught my attention.

[Caprirs]

Size doesn't matter. It's how you use it.

[shoptalk00]

Hello Caprirs,

I bought the Dyna machine and had it delivered today. I put power on it today having some issues with the screen not powering up. I can see the buttons going through a power up but the screen is dead. I noticed many different led lights in the back cabinet. Have to troubleshoot without any manuals. Please help! Thanks

[Caprirs]

Was the screen working before you got the machine? Or was it already dead and that's (partly) why it was being sold?

[shoptalk00]

I bought the machine not knowning if it worked or not. The place where the machine was stored at did not have any 3 phase power. The machine looks overall to be in good shape not used hard at all just looks like it has been in storage for a long time. I got it back to my place hooked power up and did some electrical checks everything seems to power up but screen. I would like to do some troubleshooting to see what it would take to bring this baby back to life. Do you have any experience troubleshooting this type of machine? If so, I could really use your help right now since I don't have any service manuals for this machine. Thanks

[Caprirs]

The first thing to determine is if

- the machine is booting up correctly with a dead screen or
- if the screen works but the machine isn't actually booting up

In the back cabinet, locate the Big Board. That's what Dyna called it. You might even find that printed on it. There are a bunch of LEDs to indicate various states. The ones to look at are in the middle of the board, not around the edges. There are two places with a couple banks of LEDs. When the power button is first pressed on the front control panel, these LEDs will light up one at a time sequentially "running" from one end of the bank to the other then repeating. After the PC in the front console has fully booted, started the Dyna 4M software, and established communication with the Big Board, those running lights will change to a half on/half off pattern that alternates more slowly.

If the LEDs remain do not switch from the single running pattern to the half/half pattern, the PC is not booting and establishing communication to the back cabinet. If the LEDs do change pattern, the PC is booting but the display is not coming on.

[shoptalk00]

Last night I noticed after everything was powered up that on the "big board" those two banks of LEDs were flashing together in a pattern like sequence fairly consistently. I will be back out in the shop today working on it and will take note with these LEDs. Also, I noticed that there was a video card inside the pc cabinet with a VGA serial connection port so I tried using an external monitor to see if I could boot the screen but had no luck. Is it possible to use an external monitor in this case? This machine appears to be a late 1990's (1998-1999) model based on the tags I am seeing on all the pc boards. Thanks

[Caprirs]

Depending on when it was built, the PC will be either an industrial PC with a 486 CPU or a off-the-shelf main board with a Pentium CPU. Displays varied over the years starting with monochrome and going to color later.

LEDs on the Big Board will be either:

****____
****____

or

*_*_*_*_
_*_*_*_*

The first pattern indicates the PC is booted correctly and communicating with the Big Board. The second pattern means the Big Board is powered up but not yet communicating with the PC in the front.

Need to figure if the PC isn't booting or if it's just the display.