Is anybody mucking with the Makerbot?

[paulr]

I was assuming ABS would make a good camera material, but then checked out this comparison with hardwood (doesn't mention which hardwood ... seems a bit dubious)

But the ABS doesn't look as good as I'd thought for cameras. Possibly some of the ABS/polycarbonate blends would be better. I'm not sure which printers are able to use those.

[EdSawyer]

sintered metal is no substitute to a real machined part, when it comes to strength. There are additive and subtractive machines that can do parts with the strength of a traditionally machined piece, but they are not practical or affordable for normal folks. (They are the kind of thing NASA uses).

That's well and good if you a) have a lathe, b) don't want to make 10 of something at the push of a button and c) don't want anything more complex than a circle. Strength is a function mostly of form, not the construction process; it's a little weaker than injection moulding but not so you'd notice. And if you want strength, you can print in sintered metal.

Keep in mind that most people don't own machine tools. However anyone can draw up a couple files and have them contract manufactured pretty cheaply using tools that they could never afford. You can also share/sell the IP inherent in such a design whereas if you're operating a lathe, you're effectively forced to sell your labour if you want to produce a quantity of parts for sale.

[B.S.Kumar]

sintered metal is no substitute to a real machined part, when it comes to strength. There are additive and subtractive machines that can do parts with the strength of a traditionally machined piece, but they are not practical or affordable for normal folks. (They are the kind of thing NASA uses).

Ed,
I was curious about this, so I asked a machinist about 3D printing using sintered metal. He said that annealing would increase the strength of the printed part to make it very close to a machined part. Your opinion?

Kumar

[Jim Andrada]

We use them for prototyping parts, but so far haven't found them really that useful for production parts as you're quite limited as to the materials you can use with them. And they're as slow as molasses in Antarctica. If you don't mind a production rate of one part per day they'd be fine. Small stuff like flanges or lens boards with integral flanges should take less than an hour so they'd be fine for a production run of a couple of dozen. However, for functional prototypes they save a great deal of time and let you get it closer to right before going off and spending a few hundred $k on a mold that's going to require additional modification for $$$.

For light duty stuff like lens caps and flanges they should be fine, particularly using a parametric CAD package where you could for example just input the diameter and have the flange automatically scale up keeping the same thread pitch etc.

[alec4444]

In terms of strength, it really is about the design. But it can make some pretty strong parts.... For the 3D Derby my company hosted, my team decided to build a car with a model rocket engine that could be ignited via Bluetooth. At the end of the run, there's a charge that goes off to push the parachute out (if you're using it in a model rocket). I was worried it would make the car explode, but it easily used the charge instead to eject the engine. No burns inside the car or anything.

Two drawbacks I've noticed that I haven't had time to find solutions for:
1) Parts aren't smooth. They can be sanded, but it's messy and time consuming and still not all that smooth.
2) It probably exists somewhere, but I haven't yet seen a template for threads, and I'm not sure how well they'd print.

I'm running off a lens board and some spool conversion kits for 116 to 120 film tonight or tomorrow. I'll post pics when they're done. Here's the lensboard I put on Thingiverse: http://www.thingiverse.com/thing:154964

Cheers!
--A

Edit: Another issue are the "supports" needed if you print things that stick out or otherwise float in the air. They're REALLY hard to get to in hollow areas, so trying to make a design that doesn't require supports is crucial...

[paulr]

We have to start somewhere.
http://www.thingiverse.com/thing:143882

[Jac@stafford.net]

[...] Keep in mind that most people don't own machine tools. However anyone can draw up a couple files and have them contract manufactured pretty cheaply using tools that they could never afford.

I have used this facility since the founder first went on-line. I talked to the owner long ago and he said that his dream was to allow people to design and contract manufacture as easily as ordering pizza. He buys idle and short time all over the USA.

My personal custom machinist, a real machinist and not just a CNC operator, fell into alcoholism after being "replaced by a machine" and did not come back. Very saddening.

[polyglot]

Given that people 3D print rocket engines and wing spars for aircraft, I think you can quit worrying about it being strong enough. The bulk strength is slightly lower but you can obtain much better strength/weight ratios due to the ability to include internal voids and structures that are not possible with subtractive manufacture.

[grantflanagan]

Has anyone who is skilled in CAD thought of doing a 3d printer version of the travelwide?
http://www.kickstarter.com/projects/...wide-45-camera
Because that would be awesome. I believe its just two parts that mate together, the helical focus and the body/back, then the pieces of metal that are screwed into the back.
I wish they would share their drawings!