YiorYeosa's avatar

Mechanical Iris

14 34 13K (1 Today)
By YiorYeosa   |   
Published: November 18, 2006
This is a photo of the drawing since my scanner ate most of the pencile lines no matter how sensitive the settings. This is a drawing i haven't had time jet to try in practice so let me know if i made a mistake somewhere if you should make one.

Anyway! Since i couldend find any descend drawings on the net and a lot of other people where looking for one to i tought i just post it. Since some of those numerous forum threads helped me get some usefull bits of information to begin with.

If you should try to make it you got to know it is compose out of three different basic parts.
-> The base plate; which has, in the drawing 16, holes in which the blades are positioned.
-> The Blades; which open and close the iris.
-> The Actuating Ring; is the part that is moved to open and close the iris. It has an elongated opening that functions as a guide rail to move the blades. NOTE!!!; I'm not sure if these openings should be straight or curved. But i've drawn both of them just for good mesure.

I've added points marked with letters of the alphabet (A-L) to make it easyer to find out how to design one yourself. Especialy since there are a number of different way's of constructing a mechanical iris.

The "?!" is needed for knowing where the inside line of the blade conects to the axel in the open position.

The diferent concentric cirkels in the center of the drawing are based on the measures of those used for the 16 axel holes.

If someone has more questions about them i'm more than happy to help.

Edit 7/12/06:

After some more contemplation on the subject of the shape of the rail in the actuation ring i think that the best shape is a straight line between the inner and outer position of the sliding axel.

The longer the sliding rail the longer it will take to close but also it will be more powerfull in its motion.
Image size
1567x1597px 530.96 KB
IMAGE DETAILS
Make
MEDION OPTICAL CO,LTD
Model
MD411Z3
Shutter Speed
1/21 second
Aperture
F/2.6
Focal Length
16 mm
ISO Speed
100
Date Taken
Jan 1, 2003, 12:10:40 AM
Comments34
anonymous's avatar
Join the community to add your comment. Already a deviant? Log In
Elkaddalek's avatar
ElkaddalekStudent General Artist
Cool, I was looking for one of these diagrams.
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
Glad to be of help. If you have questions feel free to ask but do read previous comments and replies. The question might already been answered. :D
I-Am-Colores's avatar
My mistake. The rounded rail, is actually the !path! on which the little peg runs. The activator ring should have the rails in the other direction! So that they push the little peg along the path!
(otherwise:
As you spin the wheel the pegs would break.)
Sorry for confusion!
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
Well thanks for the fav and all.

The drawing is just a theoretical sketch and not much more. It was basically my attempt at figuring out how they work. On the point of making it with a computer program I did not have those at the time and at the moment I don't have enough time to make it in them.
I-Am-Colores's avatar
I will do that for you!
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
Thanks but I will eventually do it myself. I just don't have the time at the moment.
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
Oops! Mea culpa the fav was by someone else!
I-Am-Colores's avatar
Oh, and the sliding rail should be a lot longer to make it easier to slide. Not necessarily straight, but about twice or three times longer rails. If you make it with high-friction materials, you have to have very long rails. And no, the pegs won't break if it's straight, but they will break if the rail is too "steep" to push it... But very good job!
I-Am-Colores's avatar
OK Very Good Job
I've been trying to do this, but I have'nt had the time to calculate everything.
You could use a photo eiting program (Photoshop) and a tool called curves to optimize the image. send me your mail in a private note and I will send you the optimized version and show you how to do it... :)
Cheers!
warground-inc's avatar
how did you draw this?
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
Pencil, calipers and a ruler.
warground-inc's avatar
what mthimatical equation or what not (not sure on wording)
basicly...how do you now where to put the points and how long the circles have to be
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
I'm afraid I can only describe it as mechanical insight. Understanding the motion. How they move to one another. Try understanding how it moves, what is needed to make it move and what would happen if you make variations to the construct.
warground-inc's avatar
oh nevermind.its really hard to ask the question. i know how it works
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
What do you want to accomplish? I might be able to help. ;)
warground-inc's avatar
its ok i got it done
jeh241's avatar
That's pretty cool. I come from a family of engineers so I've always loved technical drawings. I actually came across your piece while trying to search up information on the mechanics of a mechanical iris. Nice work!
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
Oooo! Are you gonna make one? Cause I'd like to see what you'd make of it. :D
jeh241's avatar
For one of the projects I'm working on we're building a giant robot for a game. All of the expression has to come from a single eye and that's one of the things we're putting in there, a mechanical iris. I wanted it to function realistically though. To bad it's under NDA at the moment or I'd show ya.
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
I'll wait. ;) Got my own hands full anyway. I'm restoring some very old scales. Already got the weights all cleaned up. When done I'll put up some photo's of the project.
jeh241's avatar
might be a long wait. If we ever manage to get it together though I'll come drop ya a note! Restoring the old scales sounds very interesting, I look forward to seeing it. Ahh reminds me, we found an old belt driven table saw once, probably from the 30s or 40s. We carefully restored it to working condition. It's a great saw. I got it from my grandma's uncle (when he died) along with a bunch of other old tools.
YiorYeosa's avatar
YiorYeosaHobbyist Artisan Crafter
You got any photo's posted anywhere of that bandsaw? And those old tools.

The scales are far over a century old. Non of my aunts and uncles knew of what material the dishes were made. When I first got off the verdigris, the were dirty black as far as anyone can remember, they were red. So we thought they were made of red copper first. Then I stared to polish 'em and the true luster of the metal came true. Turns out the are made of a kind of brass alloy.
jeh241's avatar
Wish I did, that was at least 6-7 years ago and a lot has changed in that time. We still have em, but they're locked up in a storage somewhere waiting to be freed.
Bowlerhatman's avatar
I meant instructions for the drawing. How all the points you have marked actually relate to each other. I understand well the principle of the blades, it's just calculating angles and curve radii is a bit tricky for me, especially if I can't see how each point is arrived at etc.
anonymous's avatar
Join the community to add your comment. Already a deviant? Log In