If I was going to micro drill stainless steel to make a pinhole, what thickness should I use, and where could I source it? So far locally I have found .010 in 430, but I think it is still a little thick. Recomendations?

Try MSC Supply or McMaster-Carr. Both carry a pretty good variety.

If I was going to micro drill stainless steel to make a pinhole, what thickness should I use, and where could I source it? So far locally I have found .010 in 430, but I think it is still a little thick. Recomendations?

Sheet stainless is made with a pinhole opening for several purposes. Tom Miller runs a pinhole web site with information on these sheets which come in packages which contain several of them. I believe that they are finer than f90 and work very well in pinhole cameras.

I don't have his current URL or e-mail, but a google search should help.

He has also taught at the Formulary and they would probably put you in touch with him.

PE

I have used brass shim stock at .001 thickness. IIRC the folks who sell pre-drilled pinholes for various focal lengths use .001 stainless. I doubt the stainless alloy would make difference with material that thin.

I will look him up, and check out the companies recommended as well. Thanks guys. To clarify what I'm doing, I know I could buy them, or laser drilled brass, etc., but my intention is to fabricate every part of this camera that I can reasonably make by myself. The camera will be an 8x10.

A quick peruse shows shim stock as the likely candidate. Any reason to choose brass over stainless or vice versa? (cost aside)

http://www.smallparts.com has both stainless and brass shim stock in 0.001 thick.

I have used the the stainless for a pin hole and with a highspeed (dremel at 30,000 rpm) drill it seemed to make a nice round hole. Small parts also has the tiny number drills that you may need to make the hole.

At the price of a single sheet of each, I would suggest buying a sheet of each and see which one you like best. The Stainless may give the best hole, but I am not certain.

This is probably well-known in the world of pinhole experts, but then again, maybe not; I found it in a 1930s Kodak book: use a blunt point such as a carpet needle or rounded center punch to make a dimple, supporting the stock on a piece of wood and tapping the needle gently. Then use a sanding block to gently thin the opposite side of the dimple until a hole is created that is round and of the proper diameter. Having tried it, I can say that it works just fine with brass shim stock, and also with aluminum from a soft drink can.

One advantage over a drilled hole is that the edges of the opening are knife-edged, which is theoretically better than a short cylinder. Also, there will be no burrs, as often occur unless the stock is sandwiched tightly between heavier material before drilling.

This is probably well-known in the world of pinhole experts, but then again, maybe not; I found it in a 1930s Kodak book: use a blunt point such as a carpet needle or rounded center punch to make a dimple, supporting the stock on a piece of wood and tapping the needle gently. Then use a sanding block to gently thin the opposite side of the dimple until a hole is created that is round and of the proper diameter. Having tried it, I can say that it works just fine with brass shim stock, and also with aluminum from a soft drink can.

One advantage over a drilled hole is that the edges of the opening are knife-edged, which is theoretically better than a short cylinder. Also, there will be no burrs, as often occur unless the stock is sandwiched tightly between heavier material before drilling.

Interesting, thanks for bringing it up. The stainless may be too hard, but I will try it with brass as well.

You might also consider the varieties of aluminum sheet sold at art and hobby shops.

To clarify what I'm doing, I know I could buy them, or laser drilled brass, etc., but my intention is to fabricate every part of this camera that I can reasonably make by myself. The camera will be an 8x10.


To me the beauty of a pinhole is an all hand made camera with a hand made pin hole and the joy to be had in doing it. I don’t get the high tech laser drilled pinhole thing at all. To me it just misses the point.

I second greybeard's suggestion. I've made several that way, the first out of an aluminum soda can sidewall (!) that is about 0.004 inches thick, the later ones (http://www.pbase.com/dw_thomas/image/75090756)out of 0.002" brass shim stock. Many -- well anyway, "good" -- hobby shops stock assortments of metal stock -- rods, tubes, strips -- and among the choices is a pack of brass shim stock in sheets about 4x6 inches in thicknesses of 1, 2, 3 and 6 mils or somewhere in there. 1 mil is pretty flimsy to handle, although with patience and good manual dexterity it's possible. 2 mil was easier. I used 400 wet-or-dry sandpaper to sand the bump down using a gentle circular motion. I would think stainless this thin could be worked easily enough too.

DaveT

I agree with DWThomas: .002" brass shim stock is easier to work with than .001". Rather than use fine sandpaper or emery paper, a very smooth and hard whetstone also works well. When making very small pinholes, I pierce the dimple with an ordinary sewing pin held in a pin vise, and keep the pin in the hole while grinding down the dimple. This slows the process down slightly for more control, and gives a fairly clean hole.

Shim stock, feeler gauge stock, emsdiasum.com for electrodeposited copper single hole 3(.15) mm diameter electron microscopy grids, around $25/100. 600 and 800 micron are standard and you couldshare them, sell them or teach a class with them.

But you did say you wanted to make your own.

At least over here mashine shop suppliers offer rolls of foil strips of different metals and thicknesses (in order to cut off pieces to make shims).

I've been tempted to try self-adhesive aluminum foil tape, but maybe remove the adhesive from a section first. I think the adhesive is thicker than the aluminum itself.

I don't do well with pin poke type pinholes, though, and it would be hard to work on the aperture edges with the adhesive near it.

I've been tempted to try self-adhesive aluminum foil tape, but maybe remove the adhesive from a section first. I think the adhesive is thicker than the aluminum itself.

I don't do well with pin poke type pinholes, though, and it would be hard to work on the aperture edges with the adhesive near it.

That is a really interesting idea Murray, I have some of that stuff around here. I'll tinker with it.

I've used .001 stainless shim stock both for pin made pinholes and laser made pinholes (I have access to a not-quite-powerful-enough laser cutter). It works really well, but it is a little difficult to handle being so thin.

my preferred pinhole material is from aluminum cans... preferably guiness as they're already black on one side ( :) ) but in a pinch any of the canned beverages will suffice. That said, I taught an elementary pinhole workshop recently and because I was in a hurry to get all the materials together we used pie tin material and it worked great.... i was surprised. good luck, keep us posted!


Tom
www.f295.org

Aren't pie "tins" the "classic" pinhole material? That and aluminum foil wrap.

I'm sure there are a lot of people that favor beverage cans filled with beer... you have to empty them before making the holes!

Aren't pie "tins" the "classic" pinhole material? That and aluminum foil wrap.

I'm sure there are a lot of people that favor beverage cans filled with beer... you have to empty them before making the holes!

This is truly a consideration, however I fear I will end up with allot of unused raw stock.

[QUOTE=Greg_E;540770]Aren't pie "tins" the "classic" pinhole material?[ /QUOTE]

Aluminum pie tins are what I have used. For blacking I use a sheet of black paper with a 1/16" hole backing up the pinhole.

The dimple and sand works the best because, as mentioned by Greybeard, it leaves a knife edge. I use a sharpening stone ['Moonstone, Case'] to sand the back. I glue the dimpled square of pie tin to the table and run the stone over it so it is as parallel to the aluminum as I can make it.

I put the pinhole in the enlarger for examination - make sure it is round, there are no burrs - and also to measure the size. Size is the hard part to control with the dimpling technique.

As there is little control of size I make several of several different sizes and then figure the optimum 'focal length' for each size.

I did the sand off the pinhole dimple trick with an aperture I made up from aluminum I salvages from the side of a standard north american soda pop can. The metal in the walls is as thin as I have ever seen. Then stick it in the enlarger like a negative, when the enlarger head is set to a known multiplication factor, like 10X, to figure out the effective aperture of your pinhole.

Go to your nearest dentist and ask for a couple strips of "dead soft matrix bands". These things cost cost next to nothing and couldn't be more perfect. They're stainless steel, and you can get six or seven holes out of one strip.

at risk of exposing how crude my methods are sometimes, here's my 2 cents:

I rarely do pinhole, but I often need a small f/22-ish aperture for cameras I make that use disposable camera lenses...I get a tiny nail red hot and burn a hole through black cardboard. Makes a nice round hole.