Astro Skeleton clock.

[MarinusK]

That is one marvelous work of art! I can't even imagine how much work has been put into all those parts.

Marinus

 

[kvom]

I was also wondering why some gear pairs are steel-brass and others are brass-brass.

 

[Buchanan]

This is the latest update on my clients website: http://www.my-time-machines.net/astro_04-17.htm

Kvom: I cut out the plates on a scroll saw. Good marking out, a fine scribe line, is a must. A low power binocular microscope helps. I use the same saw for removing the metal between the spokes on the gears. When I have a relatively fast moving small gear (pinion) driving a large gear then I make the small gear steel. if the two gears are nearly the same size and the load is light or the speed is slow( 1 revolution a day)then brass to brass is used. So far the slowest rotating part I have in the clock is one revolution in 10 000 years.
Any questions are welcome.

Thank you for the compliments.

 

[kadora]

How do you polish finished brass parts ?
How do you treat brass surface after polishing ?
How many bearings have to be oiled on mechanism ?
You should etch your name on each single part of astro clock.

 

[RonGinger]

How do you scribe the layout of such a complex part? It seems unlikely you can do it freehand, but complete geometric construction of all those small arcs would take years.

 

[kvom]

Acceptance test on 10K year part must be tricky.

 

[Herbiev]

10,000 years. Your clock will outlast the planet.

 

[kiwi2]

Hi,
You want to be careful the clock isn't deemed to be a national treasure and you are forbidden to export it when you are finished!

 

[Buchanan]

Kadora: How do you polish finished brass parts ?

I usually work through the grades of wet/dry sandpaper. Starting at 600 grit or sometimes with 250 grit if there are really deep scratches then 1000, 2500, and 5000 and then brasso.

How do you treat brass surface after polishing ?

My first choice is Gold plating but sometime lacquers and sometimes the part is left bare. On this clock all bright steel parts are stainless steel and all screws are heat blued.

How many bearings have to be oiled on mechanism ?

The barest minimum.just the fly fan bearings at the moment. Dry lube is used on sleeves and ceramic hybrid ball bearings where ever the load is large or fast.

You should etch your name on each single part of astro clock. :

I have a 'secret'Buchanan punch I made and use is random places.It is 6mm long and 2 mm high.

Ron. I have the design drawn on paper . I glue it onto the plate with contact glue, wet, and slide the paper until the design is aligned with the bearings.
then i scribe or carve along the lines with a small blade . This is not very accurate but scroll work it is good enough. All bosses around bearings are filled to filling buttons,so there is precision with no skill. when i have finished sawing out the design I file the shape until I am happy with it. You can see the knife and the paper on the brass sheet in post 16 , second last photo.

Kvon. Neither my client or myself are too worried what happens after the next fifty years!

I will post a photo of my'secret' punch tomorrow.

 

[Buchanan]

Here are two photos of the punch and the result.

 

[kadora]

Buchanan thank you for your answer.
Each your post rise new questions how do you do this or that.
Did you engrave your personal little punch by hand or
it was done by electric spark erosion machine ?

 

[bazmak]

Brilliant thread and the workmanship is unbelievable
My question,where did the design originate and how many add on designs
for each separate action and how was it all tied together.Is the full clock
designed ,drawn and being built from square 1.Are you the builder and the designer,part designer.A short tale of how all this originated etc would be very welcome Regards barry

 

[Buchanan]

Bazmak

I was approached by Mark Frank to build a dream clock. He had a comprehensive wish list. Mr. Frank is a very knowledgeable clock collector so his wish list was just as comprehensive. He sent me pictures and rough sketches of what he wanted. Then there was a period of exchanging ideas until I had a fair idea of what he wanted. i then drew a multilayered drawing of the clock. This contained most of the features in the final clock. He then asked me to produce a mock up of the clock to gauge the size and overall design.once this was complete I began to build the clock. So, yes, I designed the overall clock to a specification and then have designed and built each part. It is made of subsections or modules for ease of assembly and maintenance. I make all the parts except the dials(enamel). from the screws up. This document gives the initial design layout and also photos of the mock up. http://www.my-time-machines.net/Astro_presentation_paper_final_web.pdf so you can see the clock is a complete unit. Most individual parts are only rough sketched. but major assemblies are drawn in cross section. I have a good selection of scrap parts and spares as I often make more parts than required if there are duplicates. I am a self taught toolmaker by trade, most of my early working career was building up an injection molding factory in South Africa.
Serious clock making started when I moved to England. See www.buchananclocks.com. Then I moved to Australia, a little more like where I grew up. I have been building this clock since then while helping my sons to build up another plastic injection molding factory.

 

[kvom]

A thought occurred to me: how do you set/reset the various systems if the clock is running a bit slow or fast? Can you move the minute hand like a more simple clock, or the escapement, and thus adjust everything at one time?

 

[Buchanan]

Kvom.
All the complications are linked through one gear train. Also each separate dial or hand is on a clutch.So , you can set every thing up once, then say, if the clock stops for a week, you disconnect the complications and crank them forward 7 days and every thing is correct again. The calendar keeps track of the days, so you just keep going until the date is correct and then until the time on the 24 hour dial is correct. There is a crank for this, and it has three ratios: one turn per day. 1 turn in 6 hours and one turn for two hours This was a very definite requirement from my client: easy setting and adjustment, a good question!

 

[Buchanan]

Here are two more months of progress.
http://www.my-time-machines.net/astro_04-17.htm
http://www.my-time-machines.net/astro_05-17.htm


Working on engine turning(CNC) for the center dial. This is not complete yet. there is more to come.

 

[kvom]

I saw these updates earlier as I have been following along. Do I understand the Janvier mechanism correctly? The gear is rotated around the slanted axis by the small pinion while the horizontal shaft also rotates. Both these rotations are at constant speeds. The combination of the two motions drives the follower in the curved slot to that the shaft attached to the slot moves at a constantly varying speed.

It's difficult to tell if the two motions are in the same direction or not, looking at the video.

 

[Buchanan]

Kvom

The resulting action is exactly the same as a normal universal joint. The output accelerates then decelerated twice per revolution in relation to the input shaft.

The feed to the slant wheel adds a little to the overall speed but that is included in the calculations. What we have is, there are two factors that speed up or slow down the moon, in relation to its mean or average speed. the largest is the suns gravity which accelerates the moon when it is traveling towards the sun and decelerates it when it is traveling away from the sun. This amounts to 6 degrees of error each way. The tilt of the earth on its axis introduces another 2 and a half degrees error in the time of sunrise and set. The two slant wheels generate these oscillating errors. The greater the slant the greater the error. The speed at which each slant wheel rotates is half the period of the error. It is a little difficult to explain and more difficult to design and even more difficult to make.

 

[SilverSanJuan]

I am in awe of this project. Your craftsmanship, engineering and artistry are astounding! Thanks for sharing your talents with us. :thumbup:

 

[Buchanan]

Thanks for the compliments. But I post here to give back, not for the compliments, because learn here all the time.