Wheels - Murrells Models

To get the track to run reliably I had to help guide it in to the grove in each wheel, from this picture you can see the right hand side has not modified yet but the left hand side of the grove has been chamfered at an angle which helps guide the track links into the grove in the centre of the wheels.
Do this to all the wheels, both sides of the grove.

I also notice that wheels had some free play on their axels, if you can eliminate this free play by fitting washers on the axels between the hull and the wheel.

Drive Sprocket Modifications.

Remove the boss from the back of the sprocket as shown in the pictutre and then install the new hub as per the Kettenkrad instructions here