SWI Trak 1745P - Allin1DC Retrofit

[KreiderMachine]

Greetings All,

Today we begin work to convert our dead (computer) Trak TRL1745P Lathe to a Centroid control.

The plan is to retrofit it with an Allin1DC controller, an Automation Direct GS30 VFD, and a resistive touchscreen with the VCP, while retaining the function of the handwheels, jog stick, stop/go pendant, and estop switch.

To those of you who have done a lathe conversion before, how do you handle the gearbox, when adding a VFD? Is there a convenient way to maintain use of the mechanical gearbox without throwing off the software? We'd like to optimize for low-end torque on this machine. How would we maintain full speed range without overcooking the spindle motor? Is there an easy way to manually tell CNC12 what range it is in, or is there a way to add switch of some kind to the gear-change levers that would give the controller that information automatically?

Any recommendations you might provide for this build (while we are in the early stages, especially) are welcomed and greatly appreciated!

Thanks to all of you that helped to make our recent (first) conversion of a Millport VMC1660 to Hickory a success!

[centroid467]

With the controls that use a Wizard, there are canned input assignment settings that tell the PLC what range it is in. You'd have to replicate that functionality or it may already be in the ALLIN1DC Lathe PLC. I do not know how the switches to detect the range are typically installed but detecting the position of the selector lever might be possible using proximity switches.

[cncsnw]

If the machine has manual gear shifting (operator throws a lever), and you do not want to install switches or sensors to detect the position of the lever, then you can just edit the PLC program to use Aux keys on the jog panel (or VCP if you don't have a jog panel) to tell the control what range it is in.

In that case, it is the operator's responsibility to press the appropriate key after shifting gears.

[cncsnw]

Here is one version of a prox sensor installation such as suggested by centroid467.

On this machine, there is a recess / depression in the side of the shift lever hub, so the prox sensor turns OFF when the the lever is in that position.

In my opinion, this installation was not worth the trouble and expense. All others I have worked with, we just assigned Aux keys to indicate range.

[KreiderMachine]

@cncsnw

This is great.

What does setting up the software for either strategy involve?

On ours, each range has 4 gears. Would you advise just setting it up for L, M, and H ranges, and ignoring the other gears, or would it be easy enough to set it up for all 12 possible gear configurations?

[KreiderMachine]

@centroid467

I'll look at the pre-loaded PLC input assignments and see what I can find there, thanks.

I have the CNCpc set up as nearly as I could get it (tech bulletin #309 isn't accurate for windows 11 configuration, so I guessed on the manual windows configuration changes) Is there an updated version of this tech bulletin that applies to windows 11? (it says it is relevant to windows 11, but the control panel menus are completely different, and I was unable to find the settings described.)

[cncsnw]

On ours, each range has 4 gears. Would you advise just setting it up for L, M, and H ranges, and ignoring the other gears, or would it be easy enough to set it up for all 12 possible gear configurations?

It will be far simpler and easier if you choose no more than four gear ranges you want to use. That allows you to work with the existing infrastructure in the PLC program.

You do have a VFD, right?

In JogPanelStage, somewhere around line 2300, you should have logic similar to the following:

Code: Select all

; Use input switches, M functions, or other means to determine the gear
; range number (1-4).  For basic mills, look for one low-range switch.
; Default to high range until proven otherwise (fail-safe choice)
IF True_M THEN SpindleRange_W = 4
IF SpinLowRange_I THEN SpindleRange_W = 1

; Use the gear range number to set the range flags and speed ratio.

IF SpindleRange_W == 1 THEN SET SV_SPINDLE_LOW_RANGE,
                            RST SV_SPINDLE_MID_RANGE,
                            SpinRangeAdjust_FW = SV_MACHINE_PARAMETER_65

IF SpindleRange_W == 2 THEN SET SV_SPINDLE_LOW_RANGE,
                            SET SV_SPINDLE_MID_RANGE,
                            SpinRangeAdjust_FW = SV_MACHINE_PARAMETER_66

IF SpindleRange_W == 3 THEN RST SV_SPINDLE_LOW_RANGE,
                            SET SV_SPINDLE_MID_RANGE,
                            SpinRangeAdjust_FW = SV_MACHINE_PARAMETER_67

IF SpindleRange_W == 4 THEN RST SV_SPINDLE_LOW_RANGE,
                            RST SV_SPINDLE_MID_RANGE,
                            SpinRangeAdjust_FW = 1.0

The two lines that assign values to SpindleRange_W are what set the currently-active gear range.

If you have switches to detect when the lever(s) are in each range, then you would extend/replace the line referencing SpinLowRange_I with whatever is appropriate to your installation.

When I use Aux keys (for example, Aux1=high, Aux4=mid, Aux7=low) then it looks something like this:

Code: Select all

; Use input switches, M functions, or other means to determine the gear
; range number (1-4).

; Select spindle range with Aux keys
IF Aux1Key_M THEN SpindleRange_W = 4
IF Aux4Key_M THEN SpindleRange_W = 2
IF Aux7Key_M THEN SpindleRange_W = 1
IF True THEN SV_NV_W1 = SpindleRange_W

; Use the gear range number to set the range flags and speed ratio.

IF SpindleRange_W == 1 THEN SET SV_SPINDLE_LOW_RANGE,
                            RST SV_SPINDLE_MID_RANGE,
                            (Aux7LED),
                            SpinRangeAdjust_FW = SV_MACHINE_PARAMETER_65

IF SpindleRange_W == 2 THEN SET SV_SPINDLE_LOW_RANGE,
                            SET SV_SPINDLE_MID_RANGE,
                            (Aux4LED),
                            SpinRangeAdjust_FW = SV_MACHINE_PARAMETER_66

IF SpindleRange_W == 3 THEN RST SV_SPINDLE_LOW_RANGE,
                            SET SV_SPINDLE_MID_RANGE,
                            SpinRangeAdjust_FW = SV_MACHINE_PARAMETER_67

IF SpindleRange_W == 4 THEN RST SV_SPINDLE_LOW_RANGE,
                            RST SV_SPINDLE_MID_RANGE,
                            (Aux1LED),
                            SpinRangeAdjust_FW = 1.0

... plus, there is a line in InitialStage that sets SpindleRange_W to the last value that was stored in SV_NV_W1

Code: Select all

             SpindleRange_W = SV_NV_W1,

In this case, range 3 (high mid, Parameter 67) is never used.

[KreiderMachine]

Yes, we have an Automation Direct GS30 for it.

Thank you!