Wednesday, April 15, 2020
Update from the workshop
The tool pictured here is a spindle probe, the main function of which is to find the location of a bore (hole) in the pictured timascus mainplate. The ruby ball at the end of the probe will touch eight points inside the hole in order to calculate the diameter of the bore and its location in the XY plane to an accuracy of +/- 1.5um (micron/micrometre). 1 Micron is about 1/80th of the width of a human hair!
This tool is currently being used in the workshop to re-machine a timascus mainplate. This is due to the fact that one bore amongst a group of over 50 in the mainplate was slightly too small. Therefore, around 20um on the internal diameter needs to be taken off. So as not to disturb the location of the hole, Josh is probing it to find the true location before making any lasting alterations i.e. cutting it.
The hole is about 2.5mm in diameter, the ruby at the end of the probe is 2mm in diameter, and the endmill being used to cut off the 20um is 0.8mm in diameter which is about 10 human hairs wide! All in all, the hole has been made 0.02mm bigger. This has been a great opportunity for our new recruit James to witness first-hand how sensitive the dimensions are of these fixtures and parts made by us in house.
We have been re-machining the mainplate to be bigger than the first iterations because the incabloc (the shock protection device for the balance wheel) was being deformed when press-fit into the hole.
A rather technical update for you- but an insight on one element of the manufacturing process that we have been lucky enough to continue with during this time.