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View Full Version : Buidling a field camera - fabricating the metal parts



David R Munson
13-Oct-2003, 16:38
So I've finished drawing up plans for the wooden components of the 7x17" I want to build and am now turning my attention to the metal components. Creating the metal bits appears to be a bit more challenging than the wooden parts. Specifically, I'm referring to the metal standards for the front and back. The basic design is modeled after my Deardorff 8x10, and the metal components will be following that lead. Cutting the pieces to shape shouldn't be a problem, and I figure I can make a basic jig for bending the metal parts. Slotting is another thing entirely, though. Not quite sure where to start with that.

Anybody have any suggestions for how to go about this? I'll have a good variety of power and hand tools at my disposal. I've thought about taking some of it to a local machine shop, but I get the feeling that it would be more trouble and cost than it's worth. Suggestions are much appreciated.

Frank Petronio
13-Oct-2003, 16:44
Microtools.com has many small camera parts. Also consider buying a broken down old camera and stealing parts from it.

John Downie
13-Oct-2003, 17:15
www.mircotools.com is just a "search" site, as far as I can see.

Ernest Purdum
13-Oct-2003, 17:18
Very early brass and wood cameras had metal parts that were sawed out. Do you have a variable speed jigsaw? Or one that is belt driven so that you can change pulleys, or has a "universal" motor so that you can use an electronic variable speed control?



The traditional method of making a slot is to drill holes at each end, thread the blade through one of the holes, saw until close to a previously scribed line, then file to exact size. It's not easy, but it works. (Only on brass or soft aluminum, of course.)



For what it's worth, slots are pesky even in a well-equipped machine shop. To get it right, you have to drill the holes, then put in a milling cutter smaller than the drill bit and mill each side of the slot separately. Unless done very carefully, preferably with the aid of a digital readout, you then find out that the straight parts of your slot don't perfectly match the holes.

tim atherton
13-Oct-2003, 17:23
you need

www.micro-tools.com

or the home site

http://www.fargo-ent.com/

jnantz
13-Oct-2003, 18:34
hi dave

you might also want to check out the cameramakers mailing list there are folks there that make just about everything under the sun

http://rmp.opusis.com/mailman/listinfo/cameramakers

good luck!

-john

Todd West
13-Oct-2003, 19:33
> Anybody have any suggestions for how to go about this?

I'm still saving up to buy it (keep finding good deals on lenses ;~), but I'm planning to use a Sherline 5410A milling machine (www.sherline.com). It wouldn't be all that hard to cobble something together in aluminum using a mitre saw with a metal cutting blade (I have a Tenryu 100T TCG Alumnicut---sweet blade), some jigs, and hand drills, but a vertical mill is really the appropriate tool for the job.

If you go to a local machine shop or somebody like Acratech (www.acratech.net) it'll be cheapest to give them dimensioned drawings of what you want them to build and make it a plug and chug exercise. Cost won't be all that much lower than buying a Sherline, though.

Steve Hamley
13-Oct-2003, 19:47
David,

Call me silly but why don't you get a "dead" Deardorff or other camera and rework the hardware for the 7x17? Seems easier than making all of it yourself from scratch.

Thanks!

Steve

Mark Fisher
13-Oct-2003, 20:11
I've lurked around here thinking about doing the large format thing...figure I should contribute where I can.....

For the amount you need to do, you could use a jeweler's saw (sort of like a coping saw, but for metal)or a hack saw. You start by drilling a hole on either end the slot and file the hole long enough to get a hacksaw blade in. This would not be necessary with a jewelers saw. With either type of saw, you remove the blade from the frame, thread it though the hole, and reattach the blade to saw frame. Also, don't saw to the line (at least my line would not be straight enough!). Saw just short of the line and file the rest. Go slow and it will work out well.

Jim Galli
13-Oct-2003, 20:31
You should start with a mid '60's Burke and James 8X10 like Butch Welch did on his projects. Hey! I just happen to have one and it's for sale! And it's cheap too. What a lucky coincidence. :>))

Ralph Barker
13-Oct-2003, 22:06
For the small metal parts (aluminum or brass) that you can't find or steal, consider a Unimat - essentially a hobbyist version of a simple, miniature machinist's lathe/mill. I've had mine for about 40 years, so I don't know if they still make them new.

wfwhitaker
14-Oct-2003, 00:05
You really do need a mill in order to make the small metal parts properly. To take it to a machine shop would not necessarily be more trouble, but it would be more cost than it's worth. You would be far better off to buy a new 7x17 camera than to hire out the machine work. R&D is expensive and that's essentially where you are. And with what return on investment? Are you going into production? If you have a small shop, the tools and the skills, that's one thing. But with shop charges at around $80/hr and up, you're getting into a lot of expense.



If you can't buy new, the suggestion earlier of adapting an 8x10 or similar camera to 7x17 makes a lot of sense. It allows you to re-use the hardware without needing to have new made. All you really need to do is to build a new rear standard and get a new bellows. And Butch Welch does have some neat adaptations of Burke & James cameras.



Do you want to build cameras or do you want to make photographs? I understand. I've been there.



Regards,

Tim Curry
14-Oct-2003, 06:44
It is possible to use a router (or Dremel), carbide bit and an edge guide to mill aluminum and brass. The depth of cut is crucial to this work. A pattern follower is attached to the router's base (simple collar) and a plunge router works best. The part must be fastened to a backing board securely, a screw at each end and a recess to hold the part is best (dado the width and thickness of the stock). The edge guide is secured to the backing board to index properly, so they are mated perfectly. A series of small passes are then made with the cutter lowered slightly for each one, until the part is slotted.

To make the edge guide, a set of blocks exactly the width of the pattern follower (collar) is made first. Next some strips are cut the same thickness to serve as the edges that straddle the blocks (hardwood is best). These are then attached to a thin plywood panel (1/4" or 6mm) with glue and brads. The idea is to make this pattern and attach it to the base with screws at each corner. The base will hold the part, the pattern guides the router and depth of cut is done with the plunge router in small passes. Use a feeler gauge to set the depth of cut for each succesive pass.

Make the guide for the longest slot first and then add blocks to make smaller parts. Use eye protection (goggles that won't let chips fly in from the side), hearing protection and slow feed rates with a sharp carbide cutter. A fan will help keep the chips forced aside and out of your face. Remember to add half the difference of the cutter/collar diameters to the each end of the pattern to have a long enough slot. !BE CAREFUL!

John D Gerndt
14-Oct-2003, 07:52
IF you have an 8x10 to work from the easiest thing to do is build a rigid converter box (a pyramid shape tapering 8x10 to 7x17) to fit the 8x10 rear standard. If the locking mechanisms hold up you will only be limited in some of your movements and lens choices and still retain the full use of that 8x10 for when you want it.

John D Gerndt

Ernest Purdum
14-Oct-2003, 08:14
To comment on some of the excellent comments you've been receiving - - The idea of a 7" X 17" Burke & James is attractive, to be sure. When you are ready for bellows, having just received a fine new set of bellows from Camera Bellows in England (email sales@leefilters.com) I can recommend them highly. - - A somewhat larger version of a jeweler's saw is what was sometimes used but I think the skill required is a lot less when you have an electric motor doing the up and down part. - - A Sherline or one of the similar miniature milling machines would be nice. Be sure, though that it has enough travel to do the parts you need. A digital readout on one of these would be rather disproportionate, but dial indicators are inexpensive. If interested, "The Home Shop Machinist" (magazine) would be helpful. (http://www.villagepress.com/homeshop/) - - I've used a router to make aluminum parts but find it difficult to achieve accuracy, particularly on slots.

Bob._3483
14-Oct-2003, 08:27
Hmmm... odd that Camera Bellows can be reached at a Lee Filters e-mail address. I know they make bellows parts for Lee but perhaps the connection is more intimate? Anyway, Camera Bellows have their own site at: www.camerabellows.com.

Can't help re' construction - all thumbs here: took me two days to make an adaptor to fit Linhof panel mounted lenses to my old Arca using an Arca panel and some plywood etc...

Cheers,

Todd West
14-Oct-2003, 09:40
> And with what return on investment?

Since when did hobbies have to be a profit center?

> It is possible to use a router (or Dremel), carbide bit and an edge guide to mill aluminum and brass.

I've tried this, but have had problems controlling vibration well enough to get a good cut even at slow feeds and light cutting. Ended up cutting short and then griding to finish. Not very precise on any kind of complex part and slots aren't grindable. Tim sounds like he's a lot better at it than I am.

> Be sure, though that it has enough travel to do the parts you need.

Most mini-mills will be marginal in this respect for a 7x17. You can either deal with a couple ton, several thousand dollar mill or just step the parts on the table. Personally, I'd much rather have a mill I can lift myself, an extra three or four grand in my pocket, and the minor hassle of having to stop and shift parts halfway through a cut.

Ralph, Emco killed the Unimats back in the 1980s. There are plenty of small mill/lathe machines around, but most still weigh several hundred pounds. I personally have minimal need for turning parts (and most of that is better met by a rotary table on a mill) but if I did I'd lean towards a two tool Sherline lathe and mill setup. When you move as often as I do, it's tough to beat their portability.

David R Munson
14-Oct-2003, 10:13
Thanks for all the great suggestions. This is very good food for thought. When I get ready to build this thing, I'll look around for near-death 'Dorffs or other 8x10 fields to salvage hardware from. I'll also keep my eyes open for any existing 7x17 cameras that might happen to come up on the used market. My plan is to build one based on the general configuration of my 8x10, but what I actually do will be somewhat dependent on what resources and opportunities I do or do not have available to me once I get going on the physical construction of this thing. If a beater Korona or B&J happens to fall into my lap once I actually get around to this, I may go that route. This will certainly *not* be the last of my camera-building ventures. When I replaced the bellows on my Deardorff last year I had them made by Camera Bellows in the UK and their products really are first-rate, so I'll certainly deal with them again when I need another set fabricated.

Thanks again.

d.s.
14-Oct-2003, 10:39
If you have a drill press, then a milling table accessery might be what you need. It can be bought through discount tool catalogs. Harbor Freight is one. The milling table mounts to the drill press table and gives the ability to move the piece being worked on in all directions and with presision. One wheel moves the table left/right the other forward/back. It turns your drill press into a vertical mill. They are usually made in China, Cheap, but since you are not doing production work it should be good.

dee

Ernest Purdum
14-Oct-2003, 10:47
For Bob:



Apparently Lee Filters is the parent of Camera Bellows. I took the email address off the invoice for the nice bellows I recently received. As a further corporate step, the bottom of the invoice states "a Division of Panavision Europe Limited". Apparently some conglomeration has been going on here, but it hasn't prevented Camera Bellows from providing great service and excellent products.

Todd West
15-Oct-2003, 11:56
> Cheap, but since you are not doing production work it should be good.

Well, yeah, if you can afford the resulting dimensional slop---which depends on the design and how true you need things to run. Seems like standard procedure for doing accurate work with most of the inexpensive stuff is to rebuild the gearing and then pay a machine shop to grind the thing into tolerance. Otherwise, you live with a couple hundredths of built in error and plan accordingly.