Yes, it is 3 and a half year since the last post. I faced some insurmountable odds with the brass wheel cores. All the castings were not perfectly round and largely uneven. A friend tried to deal with them on the lathe, but after several huge interruptions he finally surrendered. Whatever reason it was: maybe the master form was not in order or the caster didn't do a good job extracting the wax pieces from the molds - it was to late to check what happenend and the parts didn't meet my expectations at all. And it wasn't possible to deal with them at all. It took some time to accept this painful and expensive loss. I learned the hard way that it never does pay to be in a hurry, driven by impatiency. I was close to bin that project.
Again: Good to have friends. Frithjof offered help to manufacture the wheelsets for the Rollwagen. This time I decided to have the wheel cores high resolution printed at Kalle Stümpfl with a glass globe strengthened resin. The prints are that exactly to press them with some slight hammering into the tires.
The tires have a collar at front side, where the cores are in contact with. We used the lathe's tailstock and a machined steel pressure piece to press the cores into the tires, whicht sat in a brass collet chuck.
It took nearly one day to construct and machine the auxiliary equipment. The next day I glued the cores with very thin CA to the tires. The slightly transparent material allows to see the CA being sucked into the seat's gap.
After that the wheels' backs were sanded down with another gauge to an equal measure for all 88 pieces. Again the lathe served to ream the axle bores to 2.95 mm for the 3mm axles.
That's the result after another long day, only interrupted by a short visit at Helmut's exhibition:
At the third day we managed to mount the axles with a special tool. The wheel is centered by a pertinax gauge and the axle via the brass sheets of the tool.
Same with the opposite side, but another pertinax gauge helped to adjust the internal flange dimension.
The gauges and auxiliary equipment being used.
Frithjof, thank you. This was far beyond my abilities.
Cheers,
Volker
