Plastic wheel and pinion fastening on TSR chassis
Posted 21 July 2011 - 02:24 PM
The cars are running great.
I used epoxy to attach the 9t pinion to the motor and the rear wheels to their axle.
Is there a smarter way?
Our response to the customer:
“We are of course happy that you are satisfied with the cars. We do our best to supply a vehicle that we feel performs well beyond the usual home-racing car in its handling and general performance, as well as its ease of driving and ability to be pushed hard.
Epoxy is fine to attach the pinion, but frankly we have never had to do it so far and never spun one! Possibly with the more powerful TSR D3 motor would it be necessary, and in that case we would recommend a light sanding of the steel shaft, a rinsing of the pinion in some kind of degreaser such as acetone or such (no worry, it will not melt!) to clean any mold release from it. We would then put a tiny drop of oil at the edge of the motor bearing to avoid any chance of the adhesive penetrating the bearing, and use either 5-minute epoxy on the shaft or another form of slow-setting epoxy, then press the pinion in its place.
It would be wise to place the pinion from its larger “entry” diameter on the motor shaft, as it would help to “pack” the adhesive in its cavity, then push it in place, with a small piece of cardboard (about 1mm thick) cut in a shape of a “U” to provide clearance as a spacer to keep the pinion from going too deep, then lifting the U-shaped cardboard piece off the motor once in proper position.
As far as the wheels, only the offside wheel from where the pinion is will ever need to be attached, and we use blue Loctite (thread locker) for this, so that the wheel is easily removable. We place a tiny drop of the blue compound in the wheel hole, then press the wheel in place while placing a small piece of tissue on the outside of the wheel to collect the excess compound. There is plenty of time to adjust for axle clearance, about 0.005”. Using epoxy there would make the wheel difficult to remove.
All the instructions above are for the 1/32 scale cars, as on the 1/24 scale chassis, there is enough wheel pressure to the shaft to never need such added process, BUT, if indeed the 45t plastic spur gear per our experience, will never spin on its axle on the 1/32 scale car, the larger 48t spur gear is looser and can benefit from being glued to the wheel using either epoxy or a droplet of cyanoacrylate glue (“Crazy Glue” or similar) between the two."
Works for us!
Philippe de Lespinay
"We are the D..., uh, the Borg. Lower your shields and surrender your ships. We will add your biological and technological distinctiveness to our own. Your culture will adapt to service us. Resistance is futile"