4X5 Field Camera, Simplified for Laser cutting, All dimensions are needed

[wombat2go]

Dan, I believe I did see those photos of your bellows some time ago .

My present camera only has "half of a bellows", that is a single sheet clamped to the body on the periphery, and clamped in a nut on the shutter thread on the other.
I made it from a composite of iron-on wet suit repair patch on the outside and Protostar flocking on the inside.
I had 2 concerns. One that it was not completely opaque, when viewing a 500 W tungsten , there was a deep red glow coming through. ( although it did not fog Fuji 160)
The second problem was that it was not quite flexible or conformable enough. So I stretched it to destruction, when the fibre of the wetsuit repair fabric let go before the telescope flocking.
( Edit error, it was the flocking that failed with radial cracks)
So the next trial is to be of the thick black plastic that Ilford paper comes in, sandwiched to the flocking with a hot iron.
I want to try to somehow pre-shape it to have a bowler hat shape.
Perhaps in the oven while wife is away...

 

[Steve Smith]

Steve is absolutely correct. That said. I've only heard of people use it for etching the surface for appearance (letters, images) but not precise depths like a 3 axis mill.

It's not precise enough that you can set a power and speed and know what depth you will get to and it depends on the material too.

I make a lot of test jigs and assembly aids using white Perspex (Plexiglass). I usually use our CNC router to cut it but sometimes I use the laser.

White Perspex cuts a lot cleaner than transparent - I have no idea why. It cuts cleanly whereas the transparent leaves a sticky residue.

I sometimes use the laser if I want a piece in a hurry. I can cut 10mm Perspex in a single pass whereas I need to cut it in five passes, 2mm at a time with the router.


Steve.

 

[Mark Fisher]

It's not precise enough that you can set a power and speed and know what depth you will get to and it depends on the material too.

I make a lot of test jigs and assembly aids using white Perspex (Plexiglass). I usually use our CNC router to cut it but sometimes I use the laser.

White Perspex cuts a lot cleaner than transparent - I have no idea why. It cuts cleanly whereas the transparent leaves a sticky residue.

I sometimes use the laser if I want a piece in a hurry. I can cut 10mm Perspex in a single pass whereas I need to cut it in five passes, 2mm at a time with the router.


Steve.

Never had that problem with clear on our cutter. Clear seems to cut fine. I've tried ABS but the edges are a bit nasty and melty. I use it a few times per month for fixtures and prototypes. I wish I had a CNC router.....with enough patience it will do most anything I'd need.

 

[Steve Smith]

I wish I had a CNC router.....with enough patience it will do most anything I'd need.

I have been spoiled by it. I used to make lots of stuff by hand. Now I think of everything in terms of "how can I CNC that?" - even things which I would previously have made on a lathe.

When I first learned how to use it, I made a 6x12 camera with it:





And I currently have a folding 5x4 camera under construction (nearly finished!).








Steve.

 

[Steve Smith]

A laser cutter generally works in two ways. Either it cuts linearly in vector (lines) or it can raster etch solid areas. I can use our laser to make 3D objects using a combination of raster and vector cutting - and regularly do.

To back up my claim, today I did an experiment.

In the first picture, the two pieces to the right were made with a CNC router. The two pieces on the left are the same design but made with a combination of raster engraving and vector cutting with a laser cutter.





My preference is for the CNC cut parts as they require much less finishing off the machine (none really - just filing off sharp corners). However, if necessary, with a bit of extra work with a file, the laser cut parts will work fine too.

The second picture shows the intended use for the pieces. It's a bracket/holder for a pneumatic microswitch.

And as of this afternoon... we have now finished building our 3D printer so I now have a third option to evaluate.




Steve.

 

[rdg]

To back up my claim, today I did an experiment.


And as of this afternoon... we have now finished building our 3D printer so I now have a third option to evaluate.


Steve.

I have had access to a laser for a while, although it is only a 40 W CO2 laser and so is unable to cut metals, as well as consumer grade 3D Printers. I really do not have access to a Milling machine but do to a CNC Router.

All three are very different machines and have very different techniques to getting the same results. And in some cases the results from one are not really obtainable from others. Of the three the 3D Printer will have the crudest products but there are techniques to clean up the appearance substantially.

Between the three technologies there should be little that you cannot make for a camera. Especially if you consider the 3D Printer as a master for making Investment Castings, also known as lost wax casting, and are willing to spend the time to really clean up the original masters.

The really nice part about the three technologies is that they are easily reproducible and the parts should be, for all intents and purposes, identical for the number of parts you make. If you want to make a small run of parts the repeatability of all three CNC tools will mean that the parts are going to be the same.

For access to many of the tools you will be able to find them in many local hacker/maker spaces and the people who know how to use them. And the Hacker/Maker movement is growing. This is a resource for making interesting small parts for a lot of projects.

Richard

 

[Steve Smith]

I have had access to a laser for a while, although it is only a 40 W CO2 laser and so is unable to cut metals

Ours is similar. I can cut 10mm Perspex at 100% power, 2% speed in a single pass but it just bounces off metal. I showed a work colleague how it wouldn't even mark the thinnest aluminium foil I could find because he didn't believe me. You can get some interesting labels by raster engraving anodised aluminium though as the anodising comes away.

All three are very different machines and have very different techniques to getting the same results. And in some cases the results from one are not really obtainable from others.

For my test, I just made all three the same but if I was going to 3D print the part I showed, I would reduce the amount of plastic in it to the bare essentials to reduce the manufacturing time. It doesn't need to be cubic in form. That's just the easiest way to CNC and laser it.


Steve.