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View Full Version : Built my own ~2lb folding 4x5!



overconfidence
2-Jul-2011, 08:36
I've been looking for a design project for a while and decided on putting together a 4x5 camera. I had plans for a folding monorail, but chose a simpler design to start:

http://img84.imageshack.us/img84/6355/omqjh.jpg

http://img94.imageshack.us/img94/9756/g9ogb.jpg

http://img833.imageshack.us/img833/4488/fyv2f.jpg

All parts are made from laser-cut flat pattern Acetal/Delrin or ABS and either snap together or are screwed in. Bellows was ordered through an ebay seller and the ground glass is poached from a Toyo back.

The camera offers geared focusing, front tilt and rise, and comes in at 2"x6.5"x9.5" and ~2lbs (need to weigh it after adding the ground glass and bellows). It lacks a bit of rigidity and could use some redesign on the focusing rail and rear standard.

This is by no means a final design, but I definitely learned a lot through the process. I would go with waterjet cutting over laser cutting for the next run, as the draft angle on some of the cut parts messed up the alignment. I think the back needs to be machined to offer accurate alignment... I would likely swap some plastic parts for machined aluminum or machined plastic.

Let me know what you guys think and any suggestions you may have :)

Additional pictures can be found here (http://imgur.com/a/GUvuT#OMQjh).

William Whitaker
2-Jul-2011, 08:45
Very ingenious!

Ash
2-Jul-2011, 08:53
Cool

cdholden
2-Jul-2011, 08:53
It's posts like this that make me wish I had worked as a machinist instead of one of the many other pointless jobs I did when I was younger. I doubt I would be doing it today, but this shows it's still a nice skill to have.
I hope you make a v2.0 to make corrections/improvements, if nothing else, for your own satisfaction.
Congratulations.

Chris

IanG
2-Jul-2011, 09:35
Very interesting, first a camera, next a coating machine please :D We'll make the emulsion :)

Ian

Frank Petronio
2-Jul-2011, 09:52
I like the convenient carry handle lol... it looks like the start of something very cool and even marketable if you refine it further.

Personally I like the folding focusing hoods from a Graphic or Toyo, they protect the ground glass on a camera like this. Or use Plexi for the ground glass.

It would be sweet if you could move the gearing to the outside and eliminate the center rail so you could leave a lens mounted, like a 8x10 Kodak 2D design. Maybe look at more older wooden camera designs that can translate to flat plastic assembly?

Wehmans are out of production ;-)

John Jarosz
2-Jul-2011, 10:09
Kudos for thinking outside the box..

Nicely done.

V2 will be superb

dave_whatever
2-Jul-2011, 10:55
F*** me thats an impressive DIY job!

Tim k
2-Jul-2011, 11:04
I'm impressed.

Light Guru
2-Jul-2011, 11:41
VARY nice. I'm currently building a Bulldog 4x5 kit myself.

If you were to offer this in a kit form to build I would definitely be interested in buying one.

Paul Fitzgerald
2-Jul-2011, 11:59
Like it alot, have fun with it.

"Let me know what you guys think and any suggestions you may have"

eliminate the center rail and try friction drive instead of gear drive like Calumet,
eliminate the excess hardware on the back
less machining, lower cost.

Sandeha
2-Jul-2011, 12:34
That shows fine thinking.

Walter Calahan
2-Jul-2011, 12:37
Excellent. Wish I had the same talents. Congratulations!!!

jb7
2-Jul-2011, 13:50
That's great, good to see different forms and approaches emerging-
Good looking camera too-

J

overconfidence
2-Jul-2011, 14:03
eliminate the center rail and try friction drive instead of gear drive like Calumet,
eliminate the excess hardware on the back
less machining, lower cost.

The center rail is definitely something that needs to get replaced. I also agree that there is a bit too much hardware.



It would be sweet if you could move the gearing to the outside and eliminate the center rail so you could leave a lens mounted, like a 8x10 Kodak 2D design. Maybe look at more older wooden camera designs that can translate to flat plastic assembly?

I put the gear in the middle because I was worried that it wouldn't focus smoothly if it were on the side. I can redesign to eliminate those kinds of focusing issues, though. I do want to get rid of that middle rail, especially because of the potential to leave a lens attached.

I've found plastic is better used to replace metal parts that plastic parts... the issue with everything being plastic is that the assembly becomes very vibration-prone. I'm almost leaning toward augmenting plastic parts with wood, since wood is also very easy to laser cut (or rout). The plastic is really nice for wear components and anything that needs fine threads, but wood may be nicer for parts like the camera base.

edit: thanks all for your support :)

Jay DeFehr
2-Jul-2011, 15:09
Looks great! Some here might be surprised you put so much time and effort into this design and then decided to share it with the community instead of seeking a patent and marketing it to us, but I'm not. I'm sure you're proud to share your work with us, and rightly so.

I have a few ideas that might be helpful, or might not. Have you considered honeycomb aluminum panels in place of the plastic for the bed? It's very lightweight, rigid, and could probably be cut the same way your plastic is. One challenge with the panels is that there are voids at the edges where it's cut, but there are solutions to that problem. One solution is to fill the voids with plastic resin. This adds rigidity to the edges, makes them safe to handle, and provides a clean finish.

Another material option is some kind of laminate panel. The panel could be laminated from any number of materials, and optimized for your design. A Balsa core with fiberglass over Cherry skins, for instance, but the possibilities are almost limitless.

If the front and back both folded down as beds, they could both be shorter and provide the same extension. This would make it more compact, but not necessarily lighter.

How about simplifying the back? If the back was magnetized, it could make for a very simple design/construction (no springs, GG frame, etc.). Imagine the GG is just the glass with one neodymium disc magnet glued to each corner. These magnets would mate to identical magnets embedded in the camera back.The thickness of the GG magnets would be equal to the T-distance of the film holders. The film holders would also be magnetized. In use, the GG would be removed, film holder attached, and the GG placed on the back of the film holder. The magnets needn't be discs, they could also be strips if it's advantageous. Clean, simple, and effective!

Really great work. Thank you for sharing it with us, and I hope you find some useful ideas here. There's a whole lot of knowledge resident in this forum, and I'm sure someone will suggest something useful. Good luck!

Heespharm
2-Jul-2011, 17:11
Could u get me one of those in 8x10.... Thanks!!

Steve Smith
2-Jul-2011, 17:27
Looks great.

As someone who has the use of both a laser cutter and a CNC drill/router, I find this very interesting!


Steve.

Curt
2-Jul-2011, 17:50
Friction isn't all that it's cracked up to be. Unless designed, machined, and adjusted it will either slip or bind. The Calumet design may look simple but it's a bit more complicated. The wheel that rides in the slot is tapered on both sided and the pressure that handles the load is by way of a spring mechanism. It's heavy fairly massive and adjusts by pressure for temperature and wear. Is very cleaver, not to be replaced with wood and rubber.

I made my first camera with a friction focus but soon replaced it with a rack and pinion. Zero backlash can be accomplished with two Belleville washers.

Pete Roody
2-Jul-2011, 17:58
Even at 3+# with the gg and bellows, you have a great design. Use it for awhile. That will tell you more about the design than we could. Very impressive.

Jay DeFehr
2-Jul-2011, 17:58
Aren't some of the Argentum cameras (http://www.argentumcamera.com/eng/pages/cameras/excursor_eng.htm) friction focus?

Michael Roberts
2-Jul-2011, 18:11
Looks great--thanks for sharing!

Uri A
11-Jul-2011, 01:57
killer job!

paulbeard
12-Jul-2011, 09:01
This is a great design exercise and I would love to know how well it performs. Regarding some of the comments on the focusing rail, here's another approach. Use a threaded rod down the center that turns a fixed nut to move the front standard: with a thumbwheel under the ground glass, turning the rod/screw would extend or retract the front standard. Have some guide tracks on the outside edges for stability and use a stop screw to lock focus. How you reconcile that with the fold down front standard is up to you: Chamonix cameras unship the whole thing and fold it down, from a video someone showed me.

This is a rough description of an idea I want to use myself, approximated from what I see in the Shen Hao cameras. Geared focus is fine but seems fiddly in terms of getting parts and implementation without any play or slop in the works but anyone can thread a nut on a bolt.

And if you post the plans, I'd love to see them: I have waterjet shops nearby and would love to see how this works.

Kerry L. Thalmann
12-Jul-2011, 21:11
Aren't some of the Argentum cameras (http://www.argentumcamera.com/eng/pages/cameras/excursor_eng.htm) friction focus?

No, the basic Argentum cameras are focused by simply sliding the standards forward and backward and then locking them in place. This is different than some of the Calumet and Gowland cameras that used a disk, turned by a knob, within a slotted rail for friction focusing.

Kerry

Gordon Flodders
13-Jul-2011, 01:54
I really like this design. Smart thinking 99 :p To give a little more rigidity I think it could be made from aluminium and still remain reasonably light weight.

GF