3D printing

[uncletony]

Rather than continue to hijack Yorki1960s DH2 build thread, I thought I'd start a thread for sharing hints/ tips / experiences using emerging 3D printing technology for creating model parts.

My experience has been as an interested observer of a professional client and friend who has a rapid prototyping shop that utilizes these technologies, sometimes for scale model prototypes to be mass produced in other media.

Wiki as usual has a pretty good if incomplete starter article:
http://en.wikipedia.org/wiki/3D_printing

At the moment possibly the most accessible vendor to get your parts printed is Shapeways:
http://shapeways.com

Finally, and of possibly no interest to anyone else here, but what the heck: I'm a Mac guy and I use Maya to create 3D assets for games and other applications. It turns out Maya / Mac can output files for shapeways with ease but there is of course a secret handshake. Google colladamaya macos to find the necessary plugin.

[Jim52]

After seeing the link in Yorki1960's thread, I ended up spending a good
part of the afternoon reading the links on the Shapeways site. That got
me to the RepRap Project and there is some very interesting reading there
too. It occurred to me that where this technology would really shine would
be in producing masters for resin casting.

Jim

[Rizzo]

I've been looking into getting a model of a Clerget printed recently. From the initial research I did, something like an Objet printer sems a good choice, for the higher resolutions available. The problem is, they require a minimum detail size of around 0.5mm, and a wall thickness of 1mm. For things like the cooling fins on the cylinder heads, I couldn't see it would work.

For the scales we're often working at, I wonder if they can really create the fine detail required yet?

[uncletony]

Rizzo, good points, and I think the answer remains "it depends". Things like true to scale 1/32 rotary engine cylinder fins might be out of reach for awhile. I suspect some of the resolution restraints imposed by the service bureaus are artificial in order to make this accessible.

This stuff is still evolving rapidly and the concept of bringing rapid prototyping to the general public is just gaining momentum, so stay tuned...

[uncletony]

Here is another contender in the race to bring 3D printing to the teeming masses:

http://i.materialise.com/

[petrov27]

Any recommendations on a decent but cheap 3D CAD application to use to attempt to create 3D printed objects? I went to school for CAD years ago and would like to take a stab at it again but the up front cost for these applications is a pretty big roadblock for me....

[Jim52]

Google Sketchup is freeware. If it will save as an .stl file, then
you should be good.

Jim

[Rizzo]

I've not used it myself (I use 3dsmax most of the time), but Blender is quite popular:
http://www.blender.org/

I think the most common format these companies ask for is STL (which Blender does seem to be able to export)

[wunwinglow]

I used Rhino 3D CAD to design a recent model project, the parts were built on a 3D Systems HD3000 machine, and I then cast them conventionally with RTV moulds and polyurethane resin. Sorry, it was an AFV, but you get the idea! www.fighting48th.com and a review at http://www.missing-lynx.com/reviews/48/fighting48thff022reviewbg_1.html .

This technology is heading our way, but the current 'desk-top' enthusiast 3D printers are very crude in comparison, at the moment anyway. Get some sample parts built before you lash out a few thousand dollars, to make sure you are happy with the level of surface finish and detail. And maybe look at desktop CNC machining, which will give you access to many more 'real' materials, and a much higher level of accuracy and finish.  If I was spending my own money, I'd get a CNC machine, hands down.....

Tim

[uncletony]

Oh for sure, the current level of "consumer" 3D printers are hopeless for what we are doing. However outsourcing parts to a bureau might be a viable option for certain bits as you yourself have demonstrated. That's what I am talking about.

And you bring up an interesting point: I am old enough to remember the dawn of "desktop publishing" and the existence of printer service bureaus where you took your color separated files (SysQuest cartridges, anyone?) to be color printed on their expensive 150 dpi color printer. There was no such thing as an affordable desktop color printer. Then there were barely affordable but extremely crappy desktop color printers, and now you can get a inkjet with amazing quality and color fidelity free in a box of cereal...

[pepperman42]

....but its a big box of cereal so its at least 5 bucks.....I hear ya - technology these days is going mach 2 so a desk top version thats usable will be around in this decade.

Steve

[Yorki1960]

You can get Autodesk Inventor Student for free. You just have to agree that you are not using it for profit.

I use my works Inventor software because it also comes with a use at home licence. Theory being you cant be in two places at once.

below is an extract of an email from the print company I use when I was originally enquiring about rapid prototyping. Just happend that he is a big helicopter RC fan and was already printing parts for them.

On the materials side it can print:
A high temperature rigid plastic, which may be good for use near turbines and hot components. Straight off the printer it will go to 67 degrees C (153 F), with a curing in the oven this increases to 80 deg C (176 F)
A high-strength ABS-like rigid plastic that holds an edge really well. This too can withstand high temperatures – after heat treatment it can go to 95 deg C (203 F).
Polypropylene-like plastics which are flexible (think a rucksack clip) - these are in translucent, grey-blue and black. The flex modulus is 1026 MPa, with very good impact properties and 44% elongation to break
Rigid Vero materials, which are strong and durable and come in a range of colours and properties
Perfectly transparent rigid plastic (perhaps cockpits and canopies etc?)
And it can also print elastomers for seals, gaskets, flexible boots etc, in a range of durometers

It cannot print metals, though you can plate the printed parts (nickel, chrome etc), and the most of the plastics can be easily painted and/or dyed. The machine can currently print 340 x 340 x 200mm sized parts, which should be more than enough for decent sized models. The resolution is 16 microns in Z.

One of the nice features I've found is printing assemblies in a single run. I've designed and printed gear trains which work, but are fully captive and printed in one pass. This means hinged and pinned model parts could be printed together and wouldn’t require further assembly.

On the resolution, I've printed 0.5mm dia holes through ~10mm parts, and these go cleanly all the way through. I guess it could also print smaller holes, but I've not tried yet.

[wunwinglow]

I agree, the bureau route is probably best right now, and I reckon will be so for some time to come. Better put your effort into the CAD modelling, and let someone else pay the telephone numbers required to buy and maintain a really good machine, than spend your cash on a device which will intrigue your for a few weeks, then irritate they heck out of you, when you discover what it really can, and can't, do. Remember, if it sounds too good to be true, it probably is.

 I just don't see the kind of 'every household will have one' kind of demand for this sort of capability. I've been in the Rapid Prototyping industry for over a dozen years, and nothing would please me more than to have a machine that produced strong, smooth, accurate parts in familiar materials (ABS is OK) that don't warp, break, need sanding smooth, take paint, glue, costs peanuts, and comes from a machine that doesn't waste most of the material you put into it, doesn't need a technician to repair/calibrate it every month, doesn't spit out cartridges for no good reason and then the supplier refuses to credit you for them, doesn't need vacuuming out twice a week... I could go on!!

It will come. But at a price. And whether it will then be commercially successful, ie if they volume of sales of machines and materials make sense for the manufacturers, I have my doubts.

Then again, maybe my slightly jaundiced views are because my experiences are from the pioneer days of 3D RP, my hat full of arrows.

Anyway, however you 'make' the final model, your CAD skills need to be up to scratch. Anyone want to compare notes on Rhino 3D, drop me a line! Heres one I did earlier...



Tim

[Des]

This is all wonderful technology, the world is going ahead in leaps and bounds, but I'm afraid all this 3D printing is way over my head. From what has been written here it appears that the process is okay, but not quite ready for our type of scale modeling, maybe in a few years we will see the advancements needed to allow this to be used in making the miniature parts we require for our models, especially the smaller scales. Once this does happen then it will be open slather for modelers to draw and print any part they will need in 3D.

Des.

[wunwinglow]

....and.....  You still have to do all the research and design effort before you get to the CAD and 3D printing stage! Some people think you just press a button and out pops the parts, but if your design is bad to start with, all you get is very quick bad parts!! The PC and its CAD software are just another set of tools, and like a Grand Piano, if you don't put a heap of effort in, it is worthless.

Tim P