Dial making Pt.14 / Blue Steel Hands

I changed the design of the steel hands into more classical one. They may suit to the brass dial, I suppose. I cut out them from steel plate and trimmed its outline with various files.

They were rubbed with many sandpapers again and again. Just a little more...

After buffing...

Bluing is the next. On the thin copper plate which filled brass chips, they are heated until their surface color will change to deep blue. To heat them at the same time might cause uneven effect. Let's do it one by one.

It has become straw color.

Purple. Nearing the end. 

It seems they were done well.

Brass bush was fitted to the hour hand. And attached to the movement.

Dial making Pt.13 / Jumping hour module 6

Lever and spring for holding the hour star wheel after quick releasing it. I have to attention to the strength of the spring.

They and the index ring were installed to the dial. Currently, this mechanism is in order.

Dial making Pt.12 / Jumping hour module 5

JUMPER. -A spring so shaped that it causes a piece to jump or move suddenly.

Donald de Carle,  WATCH AND CLOCK ENCYCLOPEDIA 

At first, I cut it off in rough shape from 0.8mm thick steel plate. Then I filed it again and again in actual matching to develop the details of its shape. 

After shaping to a certain degree, it was hardened and tempered. If this process was left out, this spring parts could not get elasticity.

Furthermore fixing the details, and I beveled and polished it.
 

Thus handmade 'JUMPER' was admitted into the parts of the module.

Dial making Pt.11 / Jumping hour module 4

The hour jump wheel was installed.

The center wheel cock needs two stud pins. These pins were made from steel. Its head was rounded and polished.

The cock was screwed on the dial plate.

Height of wheels is correct. Wheels mesh smoothly.

Dial making Pt.10 / Jumping hour module 3

Infixing the bushes to the dial plate. I drilled the holes in slightly small sizes. Adjusted with hand reamer.

All bushes were installed. Simple and light work.

Actually, I decided to change the hand winding movement from ETA2801 to Fontainemelon (FHF) 98.

<FHF98 spec>
Frequency : 21,600 A/h

Power reserve : 39h(?)

Jewels : 17
Diameter : 11 1/2 ligne (25.60mm)
Total height : 3.60mm
Mounting hight : 1.30mm
Stem hight : 1.90mm
Hand dimensions : 130/90/21 (hour/minute/seconds)

Comparison~~~

<ETA2801 spec>

Frequency : 28,800 A/h

Power reserve : 42h

Jewels : 17
Diameter : 11 1/2 ligne (25.60mm)
Total height : 3.35mm
Mounting hight : 1.80mm
Stem hight : 1.80mm
Hand dimensions : 150/90/25 (hour/minute/seconds)

ETA movements are too expensive for its appearances and function, I think. I like FHF's old fashioned looking and reasonable price, of course. There is no fear of lift-up of cannon pinion unlike ETA. Additionally it seems to be easy to be decorate. Because both diameter is the same, it is easy to change the plan.

The cannon-pinion was press-fitted with the handmade pushing parts. This parts will push and turn brass-made star wheel once an hour.

Steel-made star wheel and brass one were united by being shifted by 10 degrees.

A gap of 0.15mm are made between them. It is because of avoiding the interference of the brass wheel and spring lever.

Temporary assembled.  I checked that there are no problems with its motion.

Dial making Pt.9 / Jumping hour module 2

Continuation of making star wheels.
The wheel which was cut off was bonded on brass rod to prepare its thickness.

Hardening and tempering.

They were rolled up by wire and heated until became red color.

Removed the scale and chamfer the edge assiduously.

For now, I made these. Three types.

Dial making Pt.8 / Jumping hour module 1

I started making parts affecting jumping hour module directly. I have to make three star wheels in different sizes. This is one of them, made from steel. Twelve leaves were cut with 70 degree single angler cutter.