Jane's Clock.

[BRIAN]

Well it started with a call from my step daughter saying they will be ariving in 4 weeks for a holiday.
It just got me to thinking that it would be nice to give them a clock to take home.
So what clock ??? After making the Brass alarm most visitors to the house are facinated by the Foliot swinging on the top so that is a good start. the alarm is not very useful, but a one strike on the hour is nice to have, and simple to do,it must be simple to make as i have only 4 weeks and a lot of other things to do.
So i am throwing traditional ideas out. this clock will be made, On the fly! KISS and ASAP are the key words.

So yesterday afternoon I made a few basic notes to get the layout of the gears. and ended up with a clock that will tick 33.7 times a minute.





This afternoon its into the shop to start making chips.

I started on the escapement because I wanted to try a different method of making this component.

this scape has 2 wheels so the blanks where cut together.

To start with 15 radial cuts where made 3/8'' deep.

then the cutter was raised until its lower edge was just level with the top of the cut one slot up.

The cutter was then raised a further .020'' to give a flat top to the teeth.

Then the cutter was fed in until the to cuts met.



With the unused slides locked the remainind teeth were formed.



The dividing head was then moved onto its back to drill the fixing holes .



As the slitting saw was set up The faces of the ratchet teeth where cut also.



The back of the teeth will be formed by hand.




To finish the day I made 2 flanges for the winding system.


Well thats it started Brian.

 

[Tom Griffin]

Brian,

This sounds like an interesting project. There's nothing like striking out on your own and creating everything from scratch. It's a lot more rewarding than following drawings and adhering to a design created by someone else. I just bought Stan Bray's book "Making Clocks" and that's the approach he takes. He covers the theory behind clock design and clock making but doesn't supply any drawings. I'm already considering a redesign of the John Wilding English Regulator I was planning to make to add chimes. All I need to do is figure out where to get the time to finish my current project so I can get started.

Tom

 

[ScrapMetal]

I'll certainly be watching in awe as this comes together. :worship:

Thanks,

-Ron

 

[BRIAN]

Ok lets continue with the scape, I had drilled 3 holes to attach the 2 scape wheels to the centre boss, but the wheels need to be out of phase by half a tooth, so I moved the dividing head on 12°
and drilled 3 more holes. OK I end up with a few spare holes but I know that the assembly will be true.



Now we continue with the main wheel.

The blank was fitted to a mandrel and turned to size.



Then the mandrel was transferred to the mill for cutting the teeth.



And finally crossed out with a 12mm end mill.



That's it, 3 days down and counting. Brian.

 

[DMS]

Very nice work Brian. Can you tell me what kind of escapement this is?

 

[BRIAN]

Hi DMS.

The escapement is a "Strob" originaly used in the St. Alban's Clock. By Ritchard of Wallingford.

The foliot oscillating bar was used in the 16 century.

The star wheel is my attempt at making the constuction simple. I may make other mods as I go along to simplfy things.

All this will probably make a good clockmakers hair stand on end. but I am doing it for fun with the hope of having a clock to give to my stepdaughter.

Wish me luck Brian.

 

[BRIAN]

To drive the hands a clock has 2 pairs of gears a 12:1 set for the HR hand and a 1:1 set for the minutes,
These gears share the same centres, so the sum of the teeth must be the same for each pair.
On the brass alarm the drive pinion had 4 pins (teeth) this I did not like! so I uprated it to 5.

This meant it now had to have a HR wheel of 60 teeth; add the pinion 5 to get the sum, 65 ok.
Now if we halve this we get the number of teeth for the minute wheels. 32-1/2 teeth ,Oh Dear!!!

So we have to fudge it, we make the blank for 32-1/2 teeth but cut them with 33.
This is common in clocks.

First cut the blank to size, this gear has a very small centre hole with a 6 BA screw.
So it is locktited to its mandrel face.



Cut the gear with 33 teeth.



Lay the dividing head down, centre it under the drill, move off half PCD, then drill the 5 holes for the pinion pins.



Nearly finished gear.



Make the other one and test the meshing.



And that was it for today. Brian.

 

[BRIAN]

The next stage was to hammer in 5 short lengths of pinion steel
, trim, and grind to length.







The pinion blanks are prepaired by turning to size and keeping a small pip in the center this is used to find center when moving out to the PCD.



Then turn the bobbin , deep enough to clear the teeth of the gear but remembering that the center hole still has to be drilled.



The lathe is then set up for indexing, and the tool post drill fitted. after drilling the holes, fit the pins, grind flat, drill the hole for the arbor, then part off.



Pinion on test.



The main arbor was made from a length of 1/4" silver steel with 2 short lenghs of 1/8" ss inserted into the ends then finish turned.



And so on we go Brian.

 

[BRIAN]

If things look out of order its because I have been waiting for brass to arive.

So the next thing was to cut the notches on the Foliot ,for this I used a pinion cutter that gives a nice V notch when used in Rack mode.



This gave me the basic parts to see what it will look like.



After cuttin a few more gears I now had the ones to see if the "fudging" of the numbers worked

First the Min wheels are set up.



Thn the Hr wheel is stacked on top .




Side view All is ok.



Back to the mill for crossing out.



Getting quite a pile of parts now.




Getting on, but so is the time??


Brian.

 

[ifredaj]

Brian,
Just great that you can design a clock on scraps of paper quite awsome.I like the photos posted of various machining steps.
Will be quite a unique gift hand crafted one off original.
Ian.