How to make an Iris Diaphram watch

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Firstly I must take off my top hat and bow to Gogglerman for his wonderful creations and inspiration. He is a true artist and this project would not have been conceived if not for him and it would not have been attempted without his inspirational work. If you enjoy this project I hardily suggest you look up Gogglerman and get ready to be wowed. Now on to the fun part. I constructed this Iris aperature out of plate and sheet brass. On this first attempt at an Iris aperature I used silver solder and a propane torch to solder the pieces together. If no one has ever tried this I would submit that it is a pain in the hind quarters. On the subsequent projects after this piece I utilized a high powered electric soldering iron which proved to be much easier. Due to a lack of planning and a mistake on my part I ended up using a five leaf mechanism instead of six leaves, this gave it a slightly less than professional finish but overall I am pleased with it. I hope you enjoy it. I will add more body to this instructable as time passes so keep an eye out for changes to it and new instructables I will be posting.

Thank you Gogglerman!
(Here is a link to Gogglerman's page)

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Step 1: First thing first

Alright, the first step is to study this instructable. If you try your best to read all the directions carefully and still find yourself with questions then please feel free to contact me.

It’s a good idea to have some things down on paper before you start this project by asking yourself some questions such as “How big do I want this?” “What materials can I buy/salvage?” “What tools do I have at my disposal?” “What do I want it to look like?” Once you’ve thought through the process a little and considered your desired material and what supplies you have on hand you can adjust the directions hereafter to fit what you want. It also helps to draw out a concept of what you want the finished product to look like.

For the sake of clarity I am going to list the tools I used as well as provide some pictures of them. That list follows.
-Dremel tool
-Metal snips (The kind that cut either direction.)
-Needle nose pliers
-Small propane torch (or High power soldering iron.)
-Silver or tin solder
-Flux (Preferably non-resin.)
-Assorted small files (The more shapes the better.)
-Dremel bits (Cutting discs, small sanding drum, wire brush, sandpaper.)
-Calipers (Could also use a straight edge/square and a scribe.)
-Sharpies (Fine point and super fine. These are handy for any project or prank.)
-Ruler (It is helpful to have a stiff one and the flexible variety used for sewing.)
-Sandpaper of varying grits
-Scotchbright pads
-Pipe clamps
-Bi-metal hole saw bits
-Drill press
-Drill bits
-Refractory block (You can also use a block of wood but it doesn’t work quite as well and has a tendency to burn.)
-A couple of bowls or cups filled with water (To quench hot parts.)
-A respirator (Or dust mask.)
-Center punch (Or a nail would work)
-Brass, rawhide, or rubber hammer
-A piece of 1” diameter pipe (Or slightly larger or smaller, for bending strips into circles.)
-Scrap piece of 2X4

In addition to the tools listed you will need materials, that list follows.
-Brass or copper sheet (.032 and thinner preferably. The housing it made from a thicker brass and the leaves are from a thinner brass.)
-A ton of cheap ball point pens (The ones with the brass tips. Or you could use small brass round stock.)
-Brass plate (If you are making a solid cam plate as shown. I will also describe a cam plate made from brass sheeting and show a picture incase you can’t get any thick plate.)
-Leather (If you intend to make a leather band.)
-Graph paper (For layout of the parts)
-Unlined paper (Incase you want to do a concept drawing or write down some calculations or draw a hummingbird sipping orange soda through a crazy straw.)
-Poster board (To make a slightly more substantial pattern for parts.)
-Brass nut and bolt

PLEASE DO NOT get discouraged by these lists! These are some big lists and if you were to go out and buy all of these things for one project it would cost a ton of money. I have collected these tools over a span of some odd years but made due without them on previous projects. My point is if you don’t have all of these tools look around and ask yourself what the function of the tools are and what DO you have that would work instead? You’d be surprised at how creative you can become when you are poor or broke. I have used a file to cut thin metal before (it sucked) you could also use a jeweler’s saw, or a hacksaw with the proper care. So don’t worry. Just loosen up your creative skills and improvise.

(Safety warning)
When grinding or sanding any metals it is a good idea to have adequate ventilation and to wear a dust mask or respirator, that dust can get in your lungs. No fun. Also it is a good idea to be weary of some solders because they contain lead, so be careful and make sure to have enough ventilation to take away the fumes and be sure to wash your hands after using it.

Step 2: Bottom and top half of casing

Hey! I’m glad to see you’re still reading and you didn’t get scared off by the preliminary lists. I based my design off of the size hole saw bits I had, all I had was a 2”, 1 1/2” and a 1” bit. So I knew the diameter of my watch casing was going to be 2” . The height I just guessed at really; I knew my brass cam plate was about 1/4” thick so I had to have around 1/8” extra height overall so the leaves could sit comfortably on top of the plate and close without impeding the movement of the mechanism. I made some rough calculation and set my caliper to close to 3/8”. I then used the calipers to scribe a line on my brass sheet (.032 thick) and cut it out using a cutting wheel with my Dremel. I cleaned up the rough edges with sand paper and files and ended up with a strip of brass sheet. I then figured up the circumference of 2” by using pi (not the tasty kind, the mathematical kind) and cut the strip about 1/16” – 3/32” short. I then utilized my rubber hammer and a piece of pipe I had clamped into the vise and bent/hammered the strip into a rough circle. Then I took a pipe clamp and clamped up the strip till the ends of the strip met, making sure there was about 1/16” of the strip sticking up above the clamp. I then smeared some flux on the ends that were butting together and set that aside. I then clamped my brass sheet (.032 thick) to a piece of 2X4 and my drill press table. I then chucked up my 2” hole saw bit and made sure there was enough brass around the bit to cut a full 2” hole without cutting it yet. I then chucked up my 1” hole saw bit and cut the center hole. Then I put the 2” bit back in and cut the 2” hole making sure the center drill bit matched up with the original hole in the 2X4. This left me with a washer shaped piece. I sanded and smoothed the rough edges and placed the washer shaped piece on my refractory block, smeared some flux on it and set the brass strip (in the pipe clamp) on top of the washer piece so the brass ring (in the clamp) was touching the washer. Then I soldered the two pieces together and the ends of the ring to each other which created the top half of the watch casing. Then I quenched it in water and set that whole piece aside.

Then I used my 2” hole saw bit and cut another washer shaped piece out of my sheet brass (.032 thick) without cutting a 1” center hole. Then I cut another strip of brass but this time I made it slightly wider about 1/8” then I cut the length to match the circumference of the 2” washer piece. Then I bent/hammered the strip into a rough circle and put it in the pipe clamp but this time (after application of flux) I slid the 2” washer piece inside the strip so the strip encircled the washer. Then I clamped it down and soldered the joints together which created the bottom half of the casing. Then I took a brass nut and sanded it down till it was about 1/8” thick and soldered it around the center hole in the 2” washer shaped piece.

Step 3: Cam plate (and pie)

I then used my graph paper to layout a 2” circle which was sectioned into wedges like a pie (the tasty kind) then I drew an inner 1” circle. Then I cut on the wedge lines with a razor from the inside circle to the outside. Then I set that aside. I then clamped up my brass plate and used the 1” hole saw bit to cut an inner circle and then the 2” hole saw bit to cut the outside circle which left me with another washer shaped piece of plate. I then used my calipers to measure from the inside of the ring to the outside. I then set the caliper to half that and scribed a circle on the brass all the way around. Then I took my paper circle with the wedge lines cut out and placed it on the washer shaped piece and used a super fine tip sharpie to mark the lines onto the plate. I then used my calipers again and measured the thickness of the plate and halved that and marked a line around the entire outside of the ring. Then I used my dremel and a cutting wheel and cut down on the line to make channels in the plate to the line I marked on the plate. I then used a dremel with a sanding drum on it to sand evenly around the outside of the cam plate till it fit snuggly but still turned smoothly inside the top half of the watch casing. Then I sanded the outside of the top half of the casing and the inside of the bottom half of the casing with the sanding drum till the top half fit snuggly into the bottom half (don’t force them together because it’s a pain to get them apart).

Step 4: Leaves and things

Now on to the leaves. I started by drawing out a 1” circle with a 2” circle around it on graph paper. Then I cut the circle in half and drew a rounded end on one side and a slightly offset egg shape end on the other. On the rounded side I marked a hole about  1/8”- 3/16”  from all sides in the middle of the rounded part. Then I marked a hole at about 3/32”- 1/8” from the outside near where the end started to round inward. I then cut this out and transferred it to poster board. I poked tiny holes where I had them marked and used this template to layout the leaves on the thinner brass (.016 thick). I then cut these out using metal snips, sanded and smoothed the edges and set them aside. I then took my ball point pens and disassembled them and took the brass tip off of them. I then put the brass tips in a cup filled with water or rubbing alcohol to get most of the ink out. I then selected a drill bit that matched the diameter of the brass tip closely. I then used a center punch to make a small indention in the leaves where I had marked the holes and used the drill bit I had selected to drill in holes. I then used two pieces of wire and strung the stack of the leaves together. I then used the dremel with the sanding drum to sand all of the leaves down to match each other. I then used scotchbright on the leaves and applied flux to the holes and soldered the brass pen tips into the holes to create prongs sticking in opposite directions on either end of the leaves. I then used a cut off wheel to trim the excess bit of the prong and sanded the soldered areas relatively smooth.

Step 5: Some assembly required

I then went back to the top half of the casing and used my calipers to mark a center line all the way around the top ring then I used the piece of paper with the wedge lines cut out and marked the lines on the top ring. I then slid the top half of the casing over a block of wood and used a center punch to mark where the sharpie lines intersected with the scribed caliper line. Then I used the drill bit to drill holes where I marked with the punch. Then I stacked the leaves on the cam plate and slid it into the top half of the casing, making sure the pins in the leaves lined up with the holes in the top ring. Then I twisted the cam plate till the iris was fully opened and used a sharpie to mark a line on the bottom of the plate to the outside of the casing then I twisted the iris till it was as closed as possible and used the line on the plate as a reference and marked on the outside of the casing. This gave me the full length of travel the plate made. I then used my calipers to mark a line 1/8” from the bottom of the top casing from one mark to the other. I then used a cut off wheel to cut down that line which made a slot in the side of the casing. Then I took the assembled top half and slid it down into the bottom half as far as it would go and used a sharpie to mark a line around the top edge of the bottom half on the side of the top casing half. Then I took the top half back out and set the top half of the casing next to the bottom half. I then used the marked sharpie line on the top half to make sure it was lined up and marked a reference line where the slot was onto the bottom half. Then I marked the length of the slot on the bottom half and used the cut off wheel to cut a slot in it. Then I assembled the whole thing once more.

Step 6: Strap and watch

 I then took a small piece of brass rod and chucked it into the drill press. I then used several files to make a decorative pin which I cut to length and slid into the slot on the casing and into a slot on the cam plate. Then I tested the movement and disassembled all the pieces again. I then sanded, smoothed and polished all of the pieces using the dremel and hand sand paper and scotchbright pads. Then I measured my wrist and added around 2” in length. Then I drew out a simple design for a strap on some poster board which I cut out and transferred to some leather I selected for the strap. I carefully cut out the strap using the metal snips. Then I marked the location where I wanted the watch casing and drilled a hole in the leather that corresponded with the hole in the center of the bottom casing. Then I attached two buckles I purchased at a fabric store to one end of the strap by drilling a hole in the end of the leather piece and pushing the buckle pin through it and wrapping the leather through the buckle and drilling two holes through the top part of the leather and the tail end and sewing them together. Then I but the strap on my wrist and pulled the two strap ends through the buckle and marked where the buckle pins needed to go. Then I took the strap off and drilled a few holes in the strap ends and tested the fit. Then I took the strap off my wrist again and put one of the cut out washers from the first ring I cut onto the backside of the strap. Then I took a brass bolt that fit with the nut I had soldered into the bottom casing and pushed it through the washer and through the leather. I then took the bottom half of the casing and screwed it onto the bolt. I then marked the bolt where it came through flush with the nut and I unscrewed the casing. I then used the cut off wheel to trim the bolt to the right length. I then took a watch I purchased from the store and cut off the bands and sanded the little tabs off so it was smooth all the way around. Then I lined the watch up with the slot that the pin would go into on the cam plate and drilled out an area for the little winder on the watch to go. Then I reassembled all of the pieces and soldered the pin into the slot in the cam plate. Then I screwed the watch casing back down on the strap and used the backside of a butter knife to do some tooling on the strap.

Step 7: Done!

Now if you’re still reading, you’ve made it! Congratulations and thank you for sticking with this sometimes boring and difficult but rewarding process. I appreciate your willingness to try and do. Good luck with all your future projects. Like I said in the beginning if you have any questions now that you’ve read over the directions feel free to contact me. I look forward to adding more instructables and working with everyone to make these visions of ours a reality. I tip my top hat to you and bid you farewell till next time.

P.s. here are some pictures of the finished product.
Gibbiford11 months ago
.How on Earth will you change the battery when it dies?
ShadeStride (author)  Gibbiford7 months ago
The case comes back apart and I can acess the battery. I have hopes of integrating an automatic "self-winding" watch in another project.
Nice job! Looks wonderful. Thanks for the inspiration!
OpIvy1 year ago
Really nice project :) where can I find brass or copper sheets online for a good price?
nerd74731 year ago
rjessup1 year ago
Shade stride thanks for this instruct-able the original was beautiful but yours was much more informative.
mjursic1 year ago
Nice project. You say dremel tool--that's no dremel--it's a FOREDOM! That said, I love the project. May try to do one myself. Probably not as nice as yours, though.
ShadeStride (author)  mjursic1 year ago
Lol. Well it's a cheapo from harbor freight. But I say dremel because the same thing can be achieved with a dremel and it's a brand name that has been adopted to include any off brand rotary tool. As far as doing your own version I am probably going to put together some patterns for anyone interested in doing it. :) thanks for your comment!
could you please upload the patterns please? :D struggling a bit with the iris pieces for a different project :)
It looks like a flex shaft. Flex shafts are, in my opinion, a lot easier to use than a dremel hand tool and, I believe capable of greater speed with less vibration.
zomzilla1 year ago
out of interest: did you look at other types of iris?
if so why did you choose this type?
paqrat1 year ago
Congratulations on a very good instructable.
haynie1 year ago
what is flux for i know its for soldering but what perpous
All metals will develop an oxide film when heated. This film stops the solder from "sticking" to the metals. The flux cleans the metals being joined and protects them from oxidization until it sticks. Soldering is actually an alloying process where the surface of the metal and the solder form an alloy. This will not occur with a metal oxide in the way.
(removed by author or community request)
Then my Engineering Chemistry professor was wrong. Sorry, but the surface of the base metal and the solder do form a very thin alloy layer. The layer may only be a few atoms thick but it is an alloy.

Wikipedia : Soldering - Processes, "Soldering differs from gluing significantly in that the filler metals alloy with the workpiece at the junction to form a gas- and liquid-tight bond."
ShadeStride (author)  switch621 year ago
As far as I've researched I believe switch is right. Good explanation. :)
I'm sorry to inform you that soldering does not form an alloy. An alloy is defined as a metal made by combining two or more metallic elements, especially to give greater strength or resistance to corrosion. When soldering, the base metal and the solder metal do not combine.
I have always wanted one of these, I'll have to get around to it some day.
KontaKt1 year ago
You can't enter this in a contest! It's a copy off of a different instructable.
ShadeStride (author)  KontaKt1 year ago
Well it's loosely based on another instructable. That's true but it is different in design and the instructable on which it is based has no textual content on the construction of the object. So I had to figure all of that out on my own and I did post textual directions which are totally new from the project I loosely based this on. The methods which I used to construct this are surely different. Also my entry was approved and I do give credit to the original for the general idea so they must be aware of it. I would also point out that there are other entries based loosely on other instructables, such as goggles and there is a monocle and any number of other things which might have been inspired by other instructables. As far as instructables inspired by other instructables go that would include ALL instructables because without the first instructables posted no one would have the thought to post one.
Thank you for taking the time to document it all! That first iris diaphragm watch Instructable led me to spend a few days investigating how irises work, whereas if he had documented it as well as you have here then it would have saved me some effort!
Ok then. that sounds good.

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