Modding Logitech Marble Trackball with Cherry MX Switches

[braaaiiins]

So I thought it would be a pretty simple mod but I ran into a small problem. The omron switches used for the mouse buttons have 3 pins it seems. Cherry MX switches only have 2 pins so can someone tell me what I'm missing here. Is this mod not even possible? =(

If I get this finished, I'll be sure to upload the pictures =)

[braaaiiins]

I've got the switches working. Not sure what the third pin does, guess it doesn't matter for now. I've just got to figure out how set the switches inside permanently. I'll post some pictures when I'm done!

[dorkvader]

Yeah, often you'll have a switch like that with three pins that makes a connection to one side when not clicked, and to the other pin when clicked. Since they're very likely not using the one position, they can use it as another solder point for stability, If you look at the traces, I imagine one of the three isn't going anywhere.

If you posted a picture, I'd probably be able to say for sure.

Either way, Glad you got it working. What cherry MX type did you go with? How do you manage the greater key travel of the cherry MX?

Feel free to post pictures.

[braaaiiins]

Finally got it to work after a few hurdles. That's how every DIY goes, I suppose. I'm just waiting on my sculpting putty to dry and this baby will be ready for daily use... I hope. So far the buttons that I swapped in work fine. For some reason the buttons on the right that I have not modified have stopped functioning properly. Really annoying because I use it as a Middle Button. Not that big of a deal, pretty cheap mouse to replace. It's rather ugly, but this is really just a proof of concept for myself. My next goal is to do a bluetooth conversion. That will be sometime though. I'll have to figure out how to interface the sensor with a teensy controller. If any of you have some helpful insight on that, I'd appreciate it =)

Anyways, here are the pictures I promised. The buttons seem high because I have not actually pressed the caps all the way down. Waiting for the putty to set.

[oneproduct]

If you're looking for any more of these to fool around with give me a PM. I've got two of them sitting around that I'd be happy to get rid of for cheaper than whatever you can find these for elsewhere.

[braaaiiins]

Awesome, I'll be sure to drop you a line whenever I'm ready to get some more.

[Appeac]

Most microswitches have 3 terminals so you can set it to either normally open or normally closed depending on which pin you solder to.

[DannyBear]

Sweet mod - I'm a newb here, so please be gentle - but here it goes;

So I joined this forum specifically to hack on a scrollwheel-cum-middle mouse button to the Trackman Marble, but I'm a total ignoramus to this - any advice?

[alaricljs]

Well, that's a rotary encoder and a normally open momentary switch.  Since the device itself doesn't already sport this sort of thing you're talking about hacking a controller plus the above into the unit and figuring out how to deal with either a 2nd cable or a hacking a 2port hub into the device.  Best source for the bulk of things is a mouse that has a wheel you like.

[DannyBear]

Now I was thinking maybe I'd take the innards of a cheap optical 5-button mouse and perhaps rigging the entire thing into the housing; would that be an option?

[alaricljs]

Just don't expect to be able to use the optical sensor from that to replace what's in your TB already.  Otherwise, yeah that's a suitable option for the controller part and would come with the wheel hardware.

[braaaiiins]

I've been lusting for a scroll mod, too! But since there is no scroll function built in, I think the best option is to just start from scratch with a teensy controller and a separate optical sensor. For scrolling, I have two ideas I've been fantasizing about:

1) Joystick mod! - Dedicated joystick to handle vertical and horizontal scrolling seamlessly. This would be awesome for games with minimaps or even productivity apps that need a lot of scrolling like photoshop. Ordered some joysticks from sparkfun to play with, will try it out with the teensy.

2) Just implement scroll into the ball itself - also with teensy. The Logitech SetPoint software comes close with the universal scroll option, but it is not universal at all! It only works for the system explorer and SOME applications, thankfully chrome, but most others no, including games. Really bugs me, so if there was a button I could toggle the mouse sensor into a true scroll sensor, that would be a simple clean mod.

The key is to have side scroll too, but I don't know how to accomplish that on the teensy. There's no documentation on how to do it. I think it just requires some modification of the raw hid code. No idea where to start so if someone could help me figure it out, that would be great.

[DannyBear]

Well, those options are perfectly legitimate, but I do have a few constraints;

- I am totally new to hacking hardware.

- I am inconsolably lazy.

On top of that, I specifically want a scrollwheel because a few of the programs I use (Blender, 3D Coat, etc.) specifically use the middle mouse button a lot, and it's a pain to have to move every command on every program.  And having a scrollwheel would be nice to navigate through websites.  I think (and correct me if I'm wrong here) the cleanest/easiest solution would be to cut out the innards of a cheap 5-button mouse (like this guy here and reposition it to fit the trackball I already have somehow.  As lazy as I am, I do not use the drivers so it's okay as long as the system recognizes my trackball as a 5-button mouse.

[braaaiiins]

You could do that. Only problem I see with that is having the sensor read your movements in mirror. There's probably an easy fix for that.