Adapting The propshaft

 I was going to use a one piece Ford Escort prop shaft to transmit the drive but the prop shaft has to be shortened for the Locost set up. I clamped the shaft in the vice on the bench and physically tested each joint for wear. The joints have small needle roller bearings inside and should not be slack and wobbling around loose and worn, but also when rotated should not be tight and notchy. If there are grease nipples on the joints, give them a pump of grease until grease can be seen emerging from each joint. They should feel nice and tight but run freely.

 I marked the positions of the joints at both ends with a small file so when the shaft was cut and re-joined, it is in the same position, which will help keep the balance correct. The gearbox end UJ (universal joint) was carefully cut out of the tube prop shaft. This joint was then pushed fully onto the gearbox splines, and carefully pulled back 13mm, and taped in position to the splines to keep it there.

 A trolley jack was then used under the axle differential to jack up the rear of the Locost as if on the road condition. The front UJ was then held in line with the back axle, differential flange, and a measurement taken between the two. The prop shaft tube is then cut shorter to achieve this final length. The front UJ was then removed from the splines and tapped into the prop shaft tube with a soft Deadblow hammer. ( remember to align your marks you made before cutting the shaft). The joint should be a tight fit into the prop shaft tube. The new length prop was then offered in position.

When the prop is pushed fully onto the gearbox splines, there should be about 13mm gap between the back end prop flange and the differential flange. The shaft was then pulled back and bolted to the rear flange, and now there should be 13mm float at the front end splines so when the car axle floats up and down with bumps on the road, the prop will not lock up in position.

 The shaft was then  removed from the car and the front joint fully welded. Make sure this weld is good quality, or get a welder to do it for you, as A BROKEN PROPSHAFT IN MOTION IS A VERY DANGEROUS WEAPON. Remember it is next to your body and legs in the Locost transmission tunnel. I am not trying to worry anyone, just saying be careful, do this job right.

The finished prop shaft was then de-rusted and painted Black, and can finally be bolted in position  in the transmission tunnel.