Miniature mechanical irises?

MillenniumFalsehood · Sat Aug 29, 2015 10:38 pm

I was looking online last night for mechanical irises for a Traveller starship I'm wanting to build. I'd like them to actually work, so I can hook them up to servos. But everything seems to be either expensive or custom jobs. I need 11 of them, and I think I'd go crazy if I had to build them all by hand. Camera irises are all expensive, plus I need them all to be identical.

Can someone help me out?

Lt. Z0mBe · Post by **Lt. Z0mBe** » Sat Aug 29, 2015 11:30 pm

What about from old digital cameras? I mean old ones, or even those ones made for sale to little kids. I would think you could get them cheap.

Kenny

MillenniumFalsehood · Post by **MillenniumFalsehood** » Sun Aug 30, 2015 1:56 am

Yeah, but I need 11 of them and they need to be identical. I'll look into it, though.

Kylwell · Post by **Kylwell** » Sun Aug 30, 2015 10:21 am

The problem with camera iris's are the rarely close all the way down. Even if you modify the sliding joints you'll run into binding issues.

Have you tried American Scientific Surplus? http://www.sciplus.com/

Rocketeer · Post by **Rocketeer** » Sun Aug 30, 2015 11:34 am

This strikes me as the sort of thing that would best be 3D printed. Take a look at Shapeways:

http://www.shapeways.com/product/YKQA5U ... d=42285039

http://www.shapeways.com/product/UZ3UUS ... d=19816347

Even if these won't work, perhaps the designers could do a custom job for you.

MillenniumFalsehood · Post by **MillenniumFalsehood** » Sun Aug 30, 2015 5:14 pm

Actually, the best solution would be photoetch. I found a nice set of plans for an iris that is compact and would translate well to brass. I think I'll see if I can learn photoetching techniques and make them myself.

MillenniumFalsehood · Post by **MillenniumFalsehood** » Sun Aug 30, 2015 5:37 pm

Kylwell wrote:The problem with camera iris's are the rarely close all the way down. Even if you modify the sliding joints you'll run into binding issues.

Have you tried American Scientific Surplus? http://www.sciplus.com/

Well, them closing all the way isn't really an issue. I can copy the petals onto brass and make them close fully by extending them to a fine point.

I looked, but all they had were microscope parts.

Andrew Gorman · Post by **Andrew Gorman** » Sun Aug 30, 2015 5:55 pm

5.00 each-
http://www.surplusshed.com/pages/item/l3371.html

Rocketeer · Post by **Rocketeer** » Sun Aug 30, 2015 6:44 pm

MillenniumFalsehood wrote:Actually, the best solution would be photoetch. I found a nice set of plans for an iris that is compact and would translate well to brass. I think I'll see if I can learn photoetching techniques and make them myself.

I've had reasonably good results using MicroMark's home photoetching system. However, the size of the workpiece is limited to about 3" by 3"; and the results aren't as good as professionals can do.

http://i193.photobucket.com/albums/z256 ... CN3514.jpg

http://i193.photobucket.com/albums/z256 ... sqhtkz.jpg

http://i193.photobucket.com/albums/z256 ... seq5kn.jpg

MillenniumFalsehood · Post by **MillenniumFalsehood** » Sun Aug 30, 2015 7:23 pm

Andrew Gorman wrote:5.00 each-
http://www.surplusshed.com/pages/item/l3371.html

I'd rather use the plans for this thing: http://www.instructables.com/id/Paper-I ... /?ALLSTEPS

The parts are made from paper, and thus are compatible with metal sheet as well. I just need to take them into Illustrator and fill in the middle parts with black, then have them printed on Press'n'Peel paper. IN addition to the parts being compatible with brass sheet, the resulting iris is very compact and durable, and can be hooked up to a servo easily (which is the plan; I have a bunch of tiny linear servos from R/C helicopters for this project).

Kylwell · Post by **Kylwell** » Sun Aug 30, 2015 7:55 pm

Depends on whether the iris are overlapping, common in lenses, or flush. Most, if not all, camera lens iris's overlap making full closure impossible. Too much material in too small a space.

Those paper iris glasses are look to be overlapping.

MillenniumFalsehood · Post by **MillenniumFalsehood** » Thu Sep 03, 2015 1:46 am

Yeah, you're right... I built a prototype and it can only close to about a 1/4" hole. So I've decided to use the petal type. I have a design worked up for a nine-petal one that should work. I'll build another prototype and see how well it performs.