These are the dimensions to work to.
Note the gippo method of mounting the 4 jaw...
Progressive drilling of the bore, which needs to be 19mm. 1st drill was a 15mm which fitted the cast hole. This is a 16mm 2MT in the tailstock.
Next size available is 18mm 2MT, which struggled a bit, often catching and spinning but taking it slowly worked out.
1st attempt at boring, using my small boring head, which didn't have the depth or clearance.
Finally used the large boring head mounted on 2MT base. This had the clearance and depth, but I couldn't get a very good finish - there's no power feed on the tailstock.
The hole diameter is currently less than 19mm but greater than 18mm, which gives me room to try and lap the bore somehow. Fortunately I can make the piston to fit.
Still a lot of machining to be done, and will update when it happens.
