gfish: (Default)
gfish ([personal profile] gfish) wrote2009-07-21 03:26 pm

Electromechanical Sunglasses VIII

Got the restraining clips mounted this weekend. They got a bit marred as I bent them to shape with pliers, but I was able to clean them up quite nicely using 600 and 1000 grit sandpaper. Very satisfying. I think I might remake them, cutting them all out at once from a stack of sheet metal, instead of each independantly. I'm very happy with using the jeweler's saw to cut sheet metal, though. Goes fast, and much more precise with less collateral damage than tinsnips.


(Borrowed a proper digital camera, yay!)

The gears were sticking slightly, so I spent some time rounding off the edge of the frame so they can't snag as easily, and polishing the face of the frame up to be as smooth as possible. They run much better now. I'll probably take a tube of graphite lubricant with me just in case (nothing grease based! not with the playa dust!) but I'm not too worried. The servo should be able to handle this just fine.

I'm going down to Seattle this weekend, and there should be 3 packages waiting for me with just about everything I'll need to finish this project off. Driveshaft tubing, polarized plastic sheet, #1-64 taps and screws, and some nicer looking hex-cap screws for the gear mounts. I'm still unsure on how I'll mount the earpieces to the frame, and the servo to the earpieces, but I'm sure I can figure something out. I always have the fallback plan-b option of mounting it on a stick like a fancy masquerade mask.

I also got word today that the lasers have arrived at my parents' place, so my plans to make a LASER MEDUSA HELMET are go. Need to order some tilt sensors to have those ready. I even have some ideas for a surprisingly simple adjustment system so I can easily tweak at which angle the tilt sensors turn the thing off.

[identity profile] corivax.livejournal.com 2009-07-22 05:19 am (UTC)(link)
LASER MEDUSA HELMET sounds even better than electromechanical sunglasses!

[identity profile] ionan.livejournal.com 2009-07-22 05:44 am (UTC)(link)
That is lookin' sexx-E.

[identity profile] nojay.livejournal.com 2009-07-22 09:57 am (UTC)(link)
Suggestion? You can lose the lens gear retaining clips if you simply fit slightly-oversizewashers on top of the idler gears on the rim. Indeed if you put washers on the underside of the idler gears too that should lift the lens gears off the metal of the frames and so vastly reduce the friction between the lens gears and the frame itself.

If you want I can draw you a diagram -- I am not going to attempt to do it in ASCII.

[identity profile] gfish.livejournal.com 2009-07-22 05:06 pm (UTC)(link)
Yeah, I thought of that, and it was my backup plan if I decided I couldn't reliably drill/tap through the side of the frame. It would have been a lot simpler, certainly, but it would have covered up all the lovely gear meshing action. The point of this project is to look cool as well as to do something (vaguely) useful, so I wanted to avoid that.

So far the friction hasn't been a problem. I'm eager to keep the weight down, and particularly eager to prevent pushing the existing weight out onto further lever arms. I'll probably take washers with me, in case playa dust starts to do really unpleasant things, but for now this seems to be working quite nicely.

[identity profile] nojay.livejournal.com 2009-07-22 06:43 pm (UTC)(link)
You could fit washers under the rim gears even if you don't want to put them on top, to reduce the rubbing of the lens gears on the frame. That shouldn't affect the visibility of the gear operation. Another option would be to mount the retaining clips on the bolts that carry the rim gears -- make them elliptical in shape so the area of gear engagement is exposed but they make contact with the lens gear's top surface a few mm either side of that point. Some low-friction teflon tape on the underside of the clips would be a good idea anyways.

You could get rid of the retainers completely and still leave the gear engagement visible but the engineering (or actual cost) might be beyond your reach -- I'm thinking custom-made gears with tapered faces, conical sections in effect. The rim gears would hold the lens gears in place that way.

I love the idea but the retaining clips seem like a bodge to me, an afterthought, and I'd want to engineer them out of the equation myself if I could.

[identity profile] gfish.livejournal.com 2009-07-22 07:13 pm (UTC)(link)
Hrm. I'm pretty happy with them, with the caveat that they aren't quite identical in shape, see above. I think they add a nice kind of reticule look to the device.

I assure you I thought through all those options, though. I've been working on this design for about 3 months now. Conical gears would be awesome, but I'm already paying a ridiculous $90 for off the shelf brass gears.