[DMcKee]

We just bought (April 2013) a YooCNC 3040T. I would like to add home switches to this machine, but I think a breakout box may be unnecessary. Looking at the Parallel port/Stepper motor driver pc board I see the jumper type connectors labeled "Limit" and "X Y Z". Also there is an open spot on the board, in front of the parallel port, for a 25 pin header. Two things I'd like to find out:

1. Has anyone experimented with these spots?
2. Does anyone have a schematic for this board?

[DMcKee]

I thought this would be harder. The "jumpers" labeled "Limit XYZ" do look like I will be able to use them for home switches. The inputs are coupled through a resistor and then to an opto-coupler, the output of which connected to the parallel port. Pins are arranged as follows 12=Z, 11=Y, and 10=X.
In Mach3 I enabled the X, Y, & Z Home inputs (green check), set the port number to "1" for all, set pin numbers to X=10, Y=11, & Z=12, set all to active low (green check).
In the Diagnostic tab watch the M1 Home and connect the two pins for X and the "led" turns on.

Just have to come up with the connectors now.
Hope this can help someone else.

I still would like to get my hands on a schematic!

[DMcKee]

Ok finished adding switches and wiring. Plugged them into the connectors on the board and things are working well. Artsoft has excellent videos showing how to set up the switch table in Mach3 softwareArtSoft USA - Video Tutorials. After setting Mach3 to use the switches and clicking the Ref All Home button, it was very satisfying to watch the 3040T home and zero its axes.
If I get time later today I'll put up pics of where I placed the switches.

[DMcKee]

Here are the pix for how I mounted the home switches. Not beautiful, but functional.

[Scarb]

Just bought one of these myself but the board does not have jumpers just pin holes . Do you have a pic of your completed wiring in the control box

[RussellK]

I have the newer Carving CNC 6040-S80 machine - the PCB had unpopulated holes for homing/limit, so I populated them with pin headers in preparation for adding switches.

Haven't got around to mounting limit switches yet - I'm wondering if optical sensors are going to be more repeatedly accurate than microswitches in terms of using them for homing?

[DMcKee]

Take a look at the first picture in this thread. It's the pcb board that drives the servo motors. Look where I have the arrow pointing to the Limit XYZ switches. On mine there are three connectors that are exactly like the pins for a jumper connector on a computer mother board. I used some old jumpers that had wires on them (I don't know what they came with). But if the pins are there soldering to the board might be an option.

I used Mach3's diagnostic tab to check this out before I even began the wiring experiment. I read the material and viewed the online video to see how to set up the "Ports and pins" inputs, then carefully connected between the two pins for X, and saw the input changing on the diagnostic tab.

I think it goes without saying that these are my experiences and yours may be different. Don't hold me at fault if something goes wrong. And take care inside the servo driver box electricity is to be respected!

[Scarb]

Thanks for your reply, are your limit switches normally open or closed when when not engauged.

[DMcKee]

They are normally closed. This way if a wire breaks it will appear that the home switch has been tripped. I also want to emphasize again how helpful the Mach3 videos are; particularly the one entitled "Homing, Limits, and Offsets".

[Scarb]

Just added the pins in the control box, limit switches to the machine and wired them up. It works like a treat, now i can to a ref all and the machine homes perfectly. Thanks for your help. What software do you use for the programme, i am curruntly using CamBam and it does the job that i want. I am mainly using the machine for engraving nameplates

[DMcKee]

We've been trying the Mach 3 from Artsoft. I think we will be buying that one.

[Scarb]

I am also using Mach3 as the controlling software it works well and i am using Cambam to generate the g code

[tonyhowe1]

I think we will be buying that one.

[ken2010]

Hello all, I just found this thread and would like to add home limits to my 3040 mill. I've got the W3040T-DQ so it's got only the pin holes for the XYZ limit connector on the controller board. The holes on the PCB have solder in them - did you just stick the pin in hole, hold soldering iron tip and allow solder to melt? Is there anything close on bottom side of board? You didn't remove PCB from heat sink did you?

Thanks for any guidance and suggestions.

Ken H>

[DMcKee]

In my case the pin headers were mounted to the board already. If a person were careful you might be able to solder the wires in from the top side. This would be challenging even for experienced folks (I can't know you level of expertise). The way I was going to do it if there were no headers, was to carefully note the position of the cables, etc, and remove the board to solder in the 2-pin headers or wires. I don't know if there is heat sink compound between the driver ICs and the heat sink or not, but I would have used some when reassembling. Sorry I can't be more help to you.:rainfro:

General disclaimer: Use my advise at your own risk.

[ken2010]

DMcKee, Thanks for the info, I think I'll remove the board/heatsink assembly and solder in a 6-pin header. I sure hope there is heatsink compound, I'll use some Artic Silver on re-assembly - that's good stuff. From the looks of it the limit pins are optically isolated for safety.

Thanks for starting the thread and sharing info.

73 de Ken H>

[DMcKee]

Thanks for the feedback. It looks like your machine is set up for Z-probe (another retrofit I want to perform on ours). I see it also has some degree of spindle control. What does the little switch under the spindle connector do?

[ken2010]

There is no connector below my spindle connector, the Z-probe (touch-off function) connector is located at bottom middle of back of box. There is a two position switch on back that switches between manual speed control using the pot on front of control box, and auto control with software. The switch is labeled "H" and "M" - meaning "Hand" (manual knob on front) and "Machine" (software control) control of OFF/ON and spindle speed.

I've got the board out of box now preparing to solder a 6-pin header in and wire up a 4 pin connector to match existing connectors on back. I've got a couple of 8-pin connectors of that type, but will run to Radio Shack this morning - they show they have the 4 pin connectors in stock.

Ken

[ken2010]

I got it all soldered back together now, the TB2560AHQ chips have the pink thermal pads rather than normal heatsink compound. I got the 4-pin mic connectors at Radio Shack and pretty well got it back together. Maybe should be testing limit switches tonight.

Ken H>

[DMcKee]

If you're using Mach3 as the control software, you can easily see the switch operating by going to the Diagnostic page and looking at the status "lights". If you haven't already, check out the Artsoft (Mach3) videos (ArtSoft USA - Video Tutorials ) I found "Homing, Limits, and Offsets" to very useful when installing the Home switches.