I’ve experienced a couple of Happ trackballs recently that seemed to get stuck in one direction. Though with a little roll back and forth it would continue on it’s way. Very frustrating when trying to kill millipedes!
Fixing a sticky Happ trackball
These trackballs were brand new, though because they had been sat on the shelf for 9 months, the grease and anti-rust agents must have solidified a little. So, I have written a set of instructions on how to overcome this problem. Saying that, it’s not limited to new trackballs experiencing a rolling problem, but you might be able to revive your old Happ trackball that has seen better days rather than replacing the bearings. Well, worth a shot before replacing the 6 sets of bearings anyway.
In this article, I am servicing the 2 1/4″ version, but I believe the same goes for the 3″ too.
You will need…
Phillips screwdriver (large and small)
Drill
Countersink bit (or similar)
Blue-tac
Thin mineral oil or penetrating oil (not silicon or PTFE-based lubes)
Step 1 - Removing the screws
OK, so the first step is to open the case up by removing the 4 screws. Plus the 2 screws holding the rings crimps with earth wires.
Step 2 - Opening the case
Open up the trackball and remove the ball itself. You will see 3 rollers, each with 2 sets of bearings. Remove the 3 sets of rollers/bearings.
Step 3 - Separating the bearings
Separate the bearings from the rollers. The idler bearings will come straight off, but for the axis rollers you’ll need to remove the encoder wheel. These will be threadlocked, so grip the roller with something like a rubber glove or rubber jar-opener. Do not grip it with pliers!
You should end up with 6 bearings, ready for a bit of TLC.
Step 4 - Applying oil to the bearings
Apply a small amount of oil to the bearing access ports, running it all the way around the groove. Try not to get oil on the inner ring of the bearing as the last thing you want is oil on the trackball itself. If this happens, ensure you clean the inner thoroughly. Repeat for the other bearings on the one side only for now, and leave them face-up for 5 minutes letting gravity do it’s work. Then repeat for the other side.
You can see the 7 lubrication holes to access the bearings. For future maintenance, this can be done without taking the enclosure apart if you take a look at the trackball housing. A bit more tricky not to get oil all over the rollers!
NOTE: Don’t use WD-40 or PTFE based products for this as they will just clog up the bearings again after not too long.
Step 5 - Spinning the bearings
Now it’s time to spin the bearings. I used a countersink bit with a lump of blue-tac on the end to give it some grip. So, hold the bearing in your fingertips, spinning them up slowly at first then give them all you’ve got. I would suggest for about a minute.
Step 6 - Reassembling the shafts, bearings and encoder wheels
Dab off and excess oil from the bearings and place them back on the rollers, along with the encoder. Use the same method to ensure the encoders are on tight, ideally using threadlock. Place the ball back in the housing rolling it back and forth. You should be able to feel that the ball rolls more freely and hopefully the roller doesn’t lock up
Replace the housing and screws and you’re good to go. Ideally this should be done periodically, but we know realistically that’s not going to happen.