Building The Magnetic Clock

[George_Race]

Sage, I downloaded the 3D PDF file and it opens for me as a "Flat" 2D file. The three arrow prospective indicator is at the lower left, bottom of the drawing. But I cannot drag and rotate it.
I must be doing something incorrectly.

I did three identical pieces for the frame because I could not get any 6061T6 in 3/8 locally. Yes, I could have easily cut it by at least .030 per pass. I have a lot of .125 in stock so that is the way I went. The "Spool" piece was cut on my mill for no other reason than that I could do it. Thought it made it look more like framework, rather than one of the round moving pieces of the clock.

On Figure 15, I did a lot of creative editing on that file. I enhanced the line width, removed the center axle lines and just did what I could to make it as clear as possible.

After I downloaded the set of files from the last edition, I imported them as DXF into CamBam, used it to clean up all the notations, extra centering lines, etc and then used the cleaned up files to generate the g-code for all the flat pieces.

On the "full size" side view of the assembly drawing. I started by scanning it from the magazine in very high definition. I then clean up anything that did not look sharp an crisp. The end result was the almost exactly full size side view of the complete assembly. That is the drawing that finally brought it all together for me.

I assume you have played back my video file where I how the wheels interacted. If it would help, I could make additional movies from other views of my finished mechanism.

Thanks for the kind words about my drawings/pictures. Doing them gave me a much better understanding of how it all worked together.

You can probably tell, I am a lot more adept at doing computer stuff than machining parts. Possibly because I spent my professional life in front of a computer screen, doing almost anything that was possible to do. I guess that is why I am so fascinated with CamBam, Mach3, and CNC work in general.

George

[Sage5902]

George:

Viewing the PDF in 3D is a bit weird. Let it sit for a second to fully load and then wave your mouse around a bit. A little box should show up somewhere on your screen which says "click to activate". If you click on that some menus show up which you can use to manipulate the drawing but if you click and drag and try all sorts of things with your mouse (both button drag, the wheel on a wheel mouse etc) you can do all the stuff the menus do. Sounds like it's loading for you ok just watch for the message box. It may take a few seconds to show up. For what it's worth I'm using PDF ReaderX (10).

I did watch your movies but it took a bit of doing since it was MPG4 which is not a native format for Windows. I looked at loading a Codec from the internet but all the ones I found (on a short search) seemed to be some sort of snoopware. In the end I put it on a stick and ran it on my Wife's MAC where MP4's are a standard. It is really cool to watch the wheels interact.

Not sure why I have so much trouble with the DXF's in the download section. Especially since I'm using ACAD which were the inventors or DXF. Fig 15 just shows up partially for me. I looked at all the layers, they were turned on so I can't explain it. As for the others, many of them had disjointed lines and lines that did not intersect properly. I have seen (in other programs) some parameters you can adjust to make the program more tolerant of those things but I don't know where to set them in ACAD.

Makes no difference, I redrew everything to suit myself. The 3D model wasn't much extra work. I imported my DXF's into Alibre and it was just a matter od extruding them the correct thickness plus a whole bunch of other work as well.


Sage

[Sage5902]

Weston:

It appears that the magnets interact with each other through the back side of the wheels. Instead of magnets face-to-face.
I'm using the magnets you recommended (when I talked to you at NAMES) from United Nuclear - the really strong ones - and although they do stick to metal when acting through the aluminum the action is nothing like when the face of the magnet acts on the metal.
I'm just wondering if I have this correct and wondering why they are arranged that way.

Also

On the wheels with the bearing recesses (D&H) you have the recess at .45 OD by .23 ID. I assume this is to ensure the wheel contacts the internal bearing race first and does not touch the bearing flange. The internal race on my bearings is .235 dia. I thought it better to make the land on the wheel .240 to be sure all of the race has contact with the wheel face. Do I have the recess function correctly stated?
I assume also the OD of the recess is purposly larger than the flange on the bearings to ensure good clearance?

Sage

[Weston Bye]

Sage, yes the magnets act through the aluminum. The arrangement of the wheels concerning front-to-back is purely cosmetic. All wheels could have the magnets facing the front of the clock, or all facing toward the back, showing plain wheels with no apparent reason why the wheels would work, or it could be a mix -some forward, some reversed, although such an arrangement wouldn't appeal to me.

On wheels D&H the recess is indeed supposed to contact the inner race while clearing the flange on the outer race.

[Sage5902]

I was confused as to the way you had magnets arranged until I saw the full assembly figure 9 which shows you have them all facing forward. Fair enough.



Another question if I may.

In an earlier post you described the magnetic damper magnet holder.
Are drawings for that forthcoming?
I forgot to ask - are the two magnets arranged so they attract each other across the gap through the plate (or the opposite).


Thanks

Sage

[Weston Bye]

Sage,
The damper will be described in the Fall issue. Nothing very critical, just position the magnets about 1/16" on either side of the damper disk. The magnets do indeed attract across the gap.

[Sage5902]

Thanks Weston:

I haven't made many chips yet. I've been spending some time on the 3D drawing. I got to wondering how the clock might look if I anodized the parts. I haven't included all the parts yet but worth a look.
(With any luck there will be a working link below where you can take a look at it.)

http://www.davesage.ca/Magnetic%20Clock%20Rendered.jpg

Let me know what you think of the color combinations. I should be able to make it look pretty close to the picture (fingers crossed).

Sage

[Sage5902]

Weston:

I'm looking at a picture I took of the clock at NAMES. Can you tell be the length of the pedetals you have the clock standing on in order to clear the bezels. I'm thinkning of turning a couple of Roman columns for mine. I've made everything presented so far so I have some time to kill.

BTW what do you think of the colorized version in my previous post?

Sage

[Weston Bye]

Sage,
The columns were approximately 4" tall, but the height is not critical. Indeed, I have started on my second clock and I will probably go a little taller. The first clock, the prototype, is going to one of my daughters. I will be building several more - a numbered series - in various configurations. Brass and anodized are in the plans, as is a completely new design using the magnetic gears.

I like the idea of Roman columns, both smooth or fluted. The columns could benefit from capitals and plinths. These would be attractive in contrasting metals such as brass, but then other features or accents around the clock would have to be brass to maintain some consistency.

These are all fodder for the individual builder's imagination.

I liked your colorized drawing, but my wife didn't. I might show your drawing to prospective customers, and if it strikes their fancy I will anodize to order, as I am set up to do anodizing.

I also have gold and silver plating capability, for a price...

[dp]

I like the idea of Roman columns, both smooth or fluted. The columns could benefit from capitals and plinths. These would be attractive in contrasting metals such as brass, but then other features or accents around the clock would have to be brass to maintain some consistency.

I've a feeling someone with a Rose lathe is going to make one from woods, it will be drop dead gorgeous, and probably fetch a sweet price.