Monthly Archives: September 2019

New Cool vs Old School


In parallel to the electronic shenanigans for CNC, Bob has been applying the Mk.I grey matter to the problem of calculating the pressure required to force the crankshafts into the flywheels. For those of you who went to the old school, details are in the picture.

For those who didn’t, the upshot is that the hydraulic press we have is up to the job. We need 9.35 Tons to force fit the crankshaft. We tested the press to 11.2 Tons with some way to go. Always a tense moment though with the odd creak going on!!

CNC 1-01 Tiny steps


It might not look much, but on the table is the start of getting the Bridgeport converted to CNC operation. Nick brought his new motor and encoder round, fitted to a neat housing he made. I’d picked up an ODrive and old power supply, which we coupled to a Raspberry Pi. Igor kindly donated memory card and we were on our way!

By the time the evening was out, we’d managed to get the motor to turn through a fixed angle in either direction, run continuously at a fixed rpm, and apply a holding torque. Three critical operations for CNC. A great start, although there’s no doubting we’ve still got a long way to go.

Next steps are getting some beefier motors, fitting the odrive into a better housing and upgrading the power supply.

Oilways away.


Setting up to start drilling the oilway through the flywheel, now that the bores are final sized. It’s quite a challenge getting a flat started in the right place, on an acute angle into toughened steel. Luckily the spot cutters managed it, ready for drilling next.

There isn’t room for a centre drill, so it’ll be a delicate job drilling the pilot hole. But with a following wind the final part of the wheel will be completed ready for pressing together.

Big machines commissioned!


It’s taken a while, but the Bridgeport mill and Myford lathe are now operational with inverters providing 3-phase power and the added bonus of variable control.

First job up is to use the power feed on the quill to get a good finish and final size the bores in the flywheels. That’s going well, which is a good sign as we’ll use the same method for boring the big end for the bearings.

Long term I plan to convert the Bridgeport to CNC, but for now it’s working just fine as a manual mill – and I’m loving it!!