Trackball part 9
Trackball part 9, originally uploaded by Black Heart Industries.
Finally finished. The thing that slowed me down was whether I should add a wheel, roller, or knob to scroll web pages. I decided against it. An aluminum bracket and a piece of phenolic resin was made to mount the circuit board. The case is made of 5/8″ thick white oak, with brass screws. It measures 11″ x 11 5/8″ x 4 5/8″. The only other thing that may need adjusting is the height of the ball. It could go higher. Now I need to load Missile Command into MAME and play it the way it was meant to be played, with a gigantic trackball. For full history of this project click “Trackball” link to the right.
Trackball Mod part 8
Trackball Mod part 8, originally uploaded by Black Heart Industries.
All the electronics are now finished. I was going to make the entire ball cage a button by hinging the top back and affixing the cage to the case via a screw and a tout spring, forcing the cage against the case. A switch would be placed against the bottom of the top plate. It’s just not necessary. The only thing I have reservations about is that I use the wheel on my mouse quite often. A roller attached to the case below the wrist could serve as a wheel and a rest. Alternately, the ball as a switch could be used to change the function of the Y-axis. I’m going to live without the wheel. Measurements have been made. Next I’ll bring the clear plastic top piece and a button to the wood shop, for reference. The plastic will be used as a router and hole templet.
Trackball Mod part 7
Trackball Mod part 7, originally uploaded by Black Heart Industries.
EUREKA! I got the god damn thing to work! This is another mouse, identical to the first one. The mouse is a marvel of engineering, Only one screw to hold the thing together. Molded plastic with incredible tolerances. Built by robots. If the traces were any thinner, they would burn up from the heat of the power going thought them. One of the LEDs, from the old board, was busted. I very carefully removed one of the LEDs from the new board, and still managed to break one of the traces. I them replaced the broken LED with the new one. The boards I used don’t have any copper on them, this was a mistake. The sensors and LEDs need the traces to hold them in place. Easily fixed with more hot glue. The other LED and both sensors were left in place. The LED will draw power, but not much. The sensors are just ignored by the rest of the circuit. If you place your hand at one extreme of the ball and move it to the other, the curser will move half way across the screen. Perfect. The arcade buttons should arrive by the weekend, and I will dig out the other switch by then. Measurements will be made and then the case built.
Trackball Mod part 6
Trackball Mod part 6, originally uploaded by Black Heart Industries.
After my colossal failure, most men would have been deterred, however my response was to go and buy four more mice. I’m extremely stubborn. The Dell is probably the same as the one I dismantled before, and I will start with that one. My thought is as follows. Remove the new boards from the busted mouse board. Test each wire attached to the sensors and LEDs. Then solder the wires to the proper locations on the new mouse, not removing the sensors or LEDs from that board. Removing them is what caused the problem on the first mouse. The traces are too fine to handle the burden of disassembly.
Trackball Mod part 5
Trackball Mod part 5, originally uploaded by Black Heart Industries.
Utter failure! Sigh. The switches work but both X and Y axes don’t. I think the problem is with the wiring at the main board, it’s a mess. I’m done for today. To many other things to do tonight. Tomorrow, trouble shooting.
Trackball Mod part 4
Trackball Mod part 4, originally uploaded by Black Heart Industries.
Served up here are most of the electronics to go into the trackball. Forget everything you’ve learned about working with electronics. If your desk isn’t cluttered and the lighting inadequate then you just aren’t getting the most out of the experience. How are you going to fix your gear, in the dark corner of a stage, minutes away from show time? Don’t forget to use lots of hot glue. Not only is it ugly, it also makes trouble shooting much more difficult. Here it’s used to keep the wires from moving too much during construction. While removing the sensors and LEDs from the board, three of the incredibly thin traces broke. I had to solder directly to the chip leads. I used multicolored wire and soldered it first to the main board. This made wiring up the new boards much easier. Unfortunately I can’t test this until it’s installed. Two arcade buttons have been ordered and should be here soon. A switch will be added, along with a hinge and spring to make the entire ball cage a switch. Much thought has been giving to the case. I believe I’ve come up with the correct design, just a few more kinks to work out. Next, the mounting brackets.
Trackball Mod part 3
Trackball Mod part 3, originally uploaded by Black Heart Industries.
Before we go any further, we need to tighten our tolerances. New shorter bolts, with hex caps, for encoder disks. The spacers were replaced with treaded spacers. This takes care of the wobble, mostly. The sensor is large enough to touch the assembly. I machined down one spacer and one bolt . The X-axis has the censor on the outside and gets the machined bolt. The Y-axis on the inside and it gets the machined spacer. Added washer to X-axis spindle to take up play. The fifth bearing was cleaned, oiled, and moved toward the center. This rose the ball and centered it better. I solve problems on paper, but somethings can’t be known until they’re built.
Trackball Mod part 2
Trackball Mod part 2, originally uploaded by Black Heart Industries.
Mouse rotary encoder disks have been liberated from their plastic spindles. They each were then mounted on a 10-32 bolt with a spacer and a nut and screwed into the end of a trackball spindle. Next thing to make are mounts and the new circuit boards that will hold the sensors and LEDs. They will mount to the four tapped holes on the spindle bearing column. Some adjustment will be necessary to the spacers as they’re making the disks wobble. I think I will machine down the diameter of the screw heads. They will probably touch the sensors if not reduced. Also, there is about 1/32 ” end to end play in the X axis spindle. A washer will be added to the space next to the bearing. to remove this movement.
Trackball Mod part 1
Trackball Mod part 1, originally uploaded by Black Heart Industries.
Obscenely large trackball, $5. Obtain used USB ball mouse from fools at Goodwill, $3. Spending hours making something you don’t need, priceless. First I dismantled, cleaned and oiled giant trackball. Next I obtained working USB mouse with ball and dismantled it also. A mouse is basically an upside down trackball. The rotary encoders in the mouse are laid out in the same way in the trackball. The next step is to cut the two disks, from the mouse encoders, off their shafts, and mount them on the trackball shafts. After that, the hard part, remove both sensors and LEDs from mouse and mount onto new boards. Make mounting brackets, mount, and wire up. Test. Add two buttons. Test again. After the thing is working, then the case. Note the size difference in the trackball encoder disk and board compared to the mouse. I think that the proportions of ball to encoder rotation are about the same. In other words, if the mouse ball rolls four times to move the curser across the screen, so will the trackball’s ball.
Trackballs
Trackballs, originally uploaded by Black Heart Industries.
My god those are huge balls! 4.5 inches in diameter! I think I’ll make a computer mouse out of one. I got these at California Extreme Classic Arcade Game and Pinball Expo.
