Low Cost DIY Pendant for Mach3

[revwarguy]

At the CNC Workshop this summer, I met Randy Ray of Texas MicroCircuits who has been selling a plug an play pendant for Mach3. It is plug and play because it plugs into a USB port and looks like another keyboard to the computer. No drivers or layers of software to program, it generates the same keystrokes as if you typed the keys on the keyboard. More info here and the article in the latest issue of Digital Machinist.

I had been using a game controller with mixed success, and wanted something simpler and more powerful at the table. Randy decided to sell just the "guts" of his pendant as a kit, providing both customization opportunity as well as low cost.

Well, the "low cost" bit got my attention, so I set out to see just how low cost I could do it.

First thing is I bought his basic kit for $69.95 in the bottom mounted flavor. I added the thumbstick option as a jog joystick for $19.95. I ordered it a week ago today, and received it two days ago. Cost so far is $89.90.

A trip to my local supplier got me a Velleman G1098 project box for $3.40 and six switches at $.89 each, so I am at $98.64. I had a knob for the 1/4 inch shaft selector switch in my junk box, but I am sure you can find one for under a buck. I think the only other thing I need to buy is a strain relief snap for the keyboard cord. Looks like everything else is included.

I've attached some pics so far. One is the lid to the box, one is a printed template file I made as a drilling guide, one shows the cover mostly populated, and one shows the boards mounted under the cover. Its going to be tight in there, I definitely wouldn't use any smaller box, but it looks like everything is going fit. On a box this small, the arrangement of the controls is somewhat limited. The row of holes along the top are for LEDs, and the large blank hole is for another switch with a red button that wasn't handy when I took the picture. All other holes just have mounting screws in them like the others.

The boards are mounted on nylon standoffs (this hardware was included) that leaves room for the switches.

I know, I know, I could have CNCed the cover instead of drilling it, but my CNC is tied up with tooling to do other things right now that I didn't want to remove, and some brad point drills on the drill press worked fine and was quick. I needed to see if this box was going work.

Next is to finish the wiring and make a laminated cover for the top of the lid for the labels.

Update Real Soon Now.

[Regnar]

You know we are going to need a video of it working!

I read the article in DM and was just waiting for others to get one up and running before I pulled the trigger.

What system are you running it off of. Mach or Emc?

Looking forward to more pictures and video.

[wcarrothers1]

Personally I like the ultra cheep route. Just go to your local office supply. Buy the cheep 10-15 dollar logitec keyboard, bust it open, look at the matrix of keys to the circuit board inside (to map the keys you want to use) and solder your wires to the tabs.

Keep the milar sheet incase you want to map more keys later..hehe

I prefer the cheep Logitec classic 200 but now think its a K120.. . Prefer logitec because the tabs on the 1 banks on it's circuit board are not coated so you can solder directly to it (some other brands require you to scrap the boards to get to the coper)

I will admit it is nice to have screw terminal breakouts but untill some one comes up with one around 20 bucks I'd keep mutilating keyboards.

b.

[eloid]

PoKeys 55 allow u to make a pendant with matrix key pad( primary and secondary), lcd screen, has tons of io, encoders, inputs ,mpg, unit is a usb device and can also be used to set up control workstation Panel W/Keypad
It looks like it has great value and has lots of addons as u need them


http://www.cnc4pc.com/Store/osc/adva...keywords=pokey

[revwarguy]

I appreciate the low cost alternatives mentioned, like modded keyboards, etc. but you don't end up with a pendant, just a remoted keyboard. The cheapest alternative in this vein is a game pad, which I picked up at a garage sale for $5. But it just isn't a pendant that has both a joystick type arrangement and dedicated function keys.

Ok, here is further progress:

Pic 1 - the covers printed and laminated. I used a knife fo rthe larger holes, and a leather punch for the LED and screw holes. I printed the covers on a couple of different colored papers before laminating them.

Pic 2 - the pushbuttons installed and wired.

Pic 3 - same, but with the thumbswitch installed and the LEDs soldered in place.

Pic 4 - The main board on and the wires in place. You can see there is a lot of stuff there. This is about the smallest volume box I would dare use to get everything to fit, at 5.3 x 3.0 x 2.0 inches.

Pic 5 - Picture from the other side with all those wires inside. There are many enhancements coming, including a programming capability, so this is only 1.0 - for now it logically just looks exactly like the MP2 model. The selector switch, which has 12 possible positions, is set to just go to 10, like the MP2. I can see that the labels for the pushbuttons are obscured by the pushbutton aprons a bit, so in the next iteration I will move the labels to make them more obvious.

Pic 6 - Keyboard cable through the box with a strain relief clamp. In order to make that fit, I sanded the connector cover of the PS/2 connector round.

Next, button her up and plug her in!

I did not need the special hardware kit, and the strain relief was $.49, so the total cost comes to $90.39. (Which does not include my free junk drawer knob or a laminated cover. If you don't have a laminator, you can take it to an office supply place who will do it for a few bucks.)

eloid, how much would a pokeys55 pendant with about the same functionality end up costing?

Regnar, I'm running it off of Mach3, but I believe there is an EMC version of this coming.

[revwarguy]

Well, version one is working and I like it a lot. It moves the router easily in slow, fast, and incremental modes (as you set them in Mach), makes tool changes a lot easier, and allows you to control execution right at the table. I like being able to do this, as I can't reach across my table from being in front of the computer.

Next will come a PC program that allows customization of the buttons an switch positions, and after that a LCD display! I will be definitely be looking at some of those things.

[Khalid]

Xbox360 is a cheap solution.. If you disengrate it and make a pendant... What is the difference between your this pendant and the Xbox360? I saw almost similar functionalities within 25 US dollars!!!

[revwarguy]

Hi, Khalid.

I used to use a game controller, and I had some problems: It required some software layer to trap the "game port" USB signals and inject them into the keyboard interface. I had troubles with that, and spent some time downloading more current drivers, etc, but never could get it to be solid. Also, I took one apart and it looked pretty hard to modify, not having SMT equipment and such. All I could do with it was move the X, Y, and Z, and I reassigned most of the buttons to change from fast, slow, and incremental rates, but had trouble remembering which was which, so I ended up going back to the keyboard quite bit anyway. I know, that's is my own fault, but there it is. Also I had trouble with longer USB cables, which isn't really supported.

I wanted something where I could position the bit using different speeds, do a tool change including setting zero, start and stop the program, all while staying at the table. If you could figure out how to do a tool change at the router without going to the keyboard, tell me how - I couldn't figure it out using a game controller. If you have a small machine, where the distance between the keyboard and router bit is all within arms reach, then you probably don't need either a game controller or a pendant.

I have a larger table, and it's nice to have one.

PS I don't have any connection with the company that makes it, I just like the product.

[CarveOne]

I just bought a Microsoft Wireless Mobile Mouse 4000 this week when my old PS/2 port mouse started acting flaky and cleaning the rollers and ball did no good. The new mouse uses the very little 2.4GHz USB connector device and works on most surfaces. These devices are sold separately for around $16 usd. I wonder if one of them could be used to replace the cable interface in a pendant. This one has at least 15 feet of range. Not having a cord and not being directional would make it useful just to have the back of the pendant also act as a mouse. You could use it anywhere on the CNC table surface that is still relatively smooth. There is a lesser version of this mouse for $29.95 usd. The one I have has a wheel that can be moved sideways to scroll side to side when apps can use that feature. In fact, while typing this post I can move the cursor left and right in this Reply To Thread text editor.

CarveOne

[Khalid]

Hi again,
first i am not here to say the advertised pendant is not good.. I am thankful to Randy for providing a versatile cheap solution...

Before getting Xbox360, i don't know what useful the pendant is.. A couple of week before i got one and played with it.. And no doubt it is a good cheapest solution ever one can imagine.. Currently i am using almost all of the buttons, two joysticks, 4-custom macros etc... and i just printed on paper what button is what and it is working really fine to me..and it is my personnel opinion..

I can jog continuous and in STEPS mode just with one button click, with other button i can increase /decrease the jog step value..With one button i can incraese/decrease the Feed etc.. HOSS did a great tutorial how to took apart the Xbox and rewire it to make a beautiful pendant...Thanks Hoss...

I just write her to see what other functionality RAY pendant provide???... I Almost using all the functions with Xbox as the Randy providing in his pendant...

[revwarguy]

Originally Posted by Khalid I just write her to see what other functionality RAY pendant provide???... I Almost using all the functions with Xbox as the Randy providing in his pendant...

Khalid,

I am glad your game controller works well for you. I just had trouble getting mine to work, and there was enough frustration that there came a time when I just decided to go a different way. If you want to know about the functionality of the MP2 kit, download the manual at:

http://texasmicrocircuits.com/

Right now, the functionality is the same as his ready-to-use MP2 pendant. In the future, it will be more customizable, and will allow a LCD display to be added. Customization may require replacing the main IC, a 15$ problem.

There are more expensive alternatives the even does more, but $100 hit a nice price/performance spot for me. YMMV.

[Phife]

IMO, the wireless Xbox360 controller is the ultimate inexpensive pendant for Mach3.

Using the mach3 xbox plugin there is not need for "key grabbing" and I am able to do all the jogging, incremental, fast and slow, reference all axis, Z and XY zeroing, Cycle Start, Stop, Feedhold, and adjust the feedrate all from the controller.

I have about 20-30ft range, and its just really cool to show to people.

I see no reason to try to take the controller apart to make a pendant, its already a great pendant.

I dont ever touch the keyboard anymore, the only reason for me to go to the machine controller is to load Gcode, and to turn soft limits on and off with the mouse.