I thought I would share my fix for my TM Cougar joystick. The joystick had developed about one inch of free movement in both the "X" and "Y" axis after several hundred hours of usage.
This fix is recommended for those familiar with the dis-assembly and assembly of the HOTAS Cougar. If you are new to the TM Cougar, I would suggest a thorough reading of this website first:
http://cougar.flyfoxy.com/ The original design of the joystick has several wear points that develop in the gimbals, as shown below:
For the "Y" axis:The "Y" axis becomes sloppy due to the pivot pin elongating the holes in the handle base and gimbal cradle. The pivot pin is 3mm hardened steel, but the handle base and cradle are aluminum so the they wear at the contact points with the pivot pin.
I used four "E-Flight" bearings (#EFLH1115). These bearings have a 3mm ID by 6mm OD with a 2mm depth. Using a drill press, I drilled out seats for the bearings where the pivot pin goes through the handle base and the gimbal cradle. I used a 7/32 and 15/64 drill bit to drill the seats, but I would recommend getting a 6mm drill bit at the same time you get the other parts.
*Note: I did NOT drill all the way through the handle or gimbal cradle. Drill just deep enough for the bearings to seat flush into the handle and gimbal cradle* It is important that you drill the bearing seats as close to 90 degrees to the faces of the handle base and gimbal cradle, otherwise the pivot pin will not line up with the bearings. I used a drill press with a vise and torpedo level, but you could also have the parts drilled out at a machine shop for less than an hours labor charge.
I then pressed the bearings into the seats. The following photos show a before and after on the handle base and gimbal cradle:
When assembling the "Y" axis gimbal, I used 3x6MM washers made by "Traxxas" to keep the bearings seated:
Total cost for parts was $14 and they were found at my local hobby shop that caters to R/C cars and micro-helicopters.
For the "X" axis:The "X" axis becomes sloppy due to the rough finish of the handle base and gimbal opening for the handle base.
First, I used a Dremel tool with a small felt rotary pad and some plastic buffing compound to polish the opening in the "X" axis gimbal cradle to a mirror finish.
If you don't have a Dremel tool you could do it by hand using Micro-mesh Kr-70 Acylic Restoration Kit. This kit runs about $30 and can also be used to repair scratched DVD's, CD's, or any plastic. Just start with the coarser grit sandpaper, working through the finer grits until you are just using the buffing compound.
Be careful not to take off too much metal. You just want to smooth out the finish not elongate the opening.
After polishing the gimbal cradle, I used some PVC heat-shrink tubing placed over the very bottom of the handle shaft that rides in the gimbal cradle.
The heat shrink tubing needs to have a gloss finish to it, not the standard matt finish. Remember gloss = smooth finish. I found some at HomeDepot. The sides of the handle shaft that contact the gimbal cradle might need to be sanded slightly to allow the heat shrink to fit between the handle and gimbal. After shrinking the tubing on the handle base, I placed a dab of hot glue at the very bottom of the handle base to ensure the heat shrink tubing did not slide off the end. After reassembly I applied a light coat of lithium grease between the heat shrink tubing and gimbal opening. This is what the gimbals looked like re-assembled:
The end result is that the play in the joystick went from approximately one inch in each direction to 1/8 of an inch (measured at the top of the joystick). I have put over 30 hours on the joystick and it has not loosened in the least. If and when it does become loose the parts are easy and cheap to replace.
Hope this helps.
