Part 11 By Vince Cutajar

The tapered flywheel collet was machined from a piece of 15mm BMS. I drilled and reamed the hole 8mm. When I took it out of the chuck I thought, "Why not do another one at the other end, just in case". Problem was that I had not faced the other side and I could not disturb the lathe setup, so I milled the face of the bar.

Did the taper and 8mm hole on the other side of the bar .

Parted off one of the collets, and hacksawed the slot (I was too lazy to setup the slitting saw in the mill). So I marked the centre line of the collet, clamped it in the milling vice just above the centre line and started the slot with a hacksaw blade supported on the vice jaws. I then turned it 90 deg and used the hacksaw to continue cutting the slot. Deburred the collet and gave it a try on the mandrel I had previously made. It really clamps the flywheel nicely. Only problem I can anticipate, is that if I had to remove the flywheel from the actual engine, most probably I would need a puller.

Next I machined the pulley groove with the tool I had already made. Made sure that the tool was at exactly 90 deg to the flywheel by using a DTI. I machined the groove very, very slowly and thankfully the material used for the flywheel (from the kit) had good cutting qualities.
Next job was the shaft nut, as Westbury calls it.
The cylinder liner was bored to 25.35mm (25.4mm should be the final diameter after honing). And finished the outside diameter to dimension.
Finished the cast iron cylinder liner. All it needs is honing but that will be done after the liner is pressed into the aluminium cylinder.
Making the cams was tested on a piece of aluminium. The calculations worked and the cams proper were made from a piece of 5/8" silver steel that came with the kit. I used the same method that I used in the previous trial cut of the cams. They came out fine and to dimension. I had the same problem that I had when I did the trial cut, namely from where to start the second cam to keep the correct angle between the cams. I always get confused when angles come into play. All I can say that I spent nearly an hour fussing over it to get the correct angle.

The hole in the cams was made 6mm, so I had to reduce the camshaft from 7mm to 6mm.

Next onto the gears. I decided to increase the hole in each gear to the required diameter, namely 6mm for the 40T gear and 8mm for the 20T gear. To do this I held the gears in the milling vice between soft jaws (to protect the teeth) on a couple of parallels. I made an arbor for the gears which fits tightly in the original hole so that I can locate it under the drill chuck. Drilled the hole on 0.5mm increments and reamed it. Made a trial fit of the gears to see if they mesh correctly and was pleased that they actually do and turn smoothly. 
Started with the spur brass gear and used a 6mm expanding mandrel to machine it to size. Used a profile tool for some bling.
I then worked on the pinion steel gear and used an 8mm expanding mandrel I had previously made to machine it to size.

The timing gears are now finished. The pinion gear will be pinned to the crankshaft at a later stage and the spur gear and also the cams will need to be broached for a keyway.

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