Getting off the ground: printing a rocket

Hobbes · August 24, 2011, 04:30:47 AM

Thanks Chris, I'm doing this project as an experiment, the idea fascinates me as well. Drawing the parts is complicated, then again scratchbuilding these shapes wouldn't be easy either. I'm basically trading PSR time for upfront effort.

frank2056 · August 24, 2011, 06:42:28 AM

I think of it as a slightly different form of scratchbuilding, although there should be much less PSR with the two high end materials you'll be using. Your parts may even be ready to go with little or no PSR beyond a layer of primer.

GTX · August 26, 2011, 11:17:01 AM

You're actually dabbling in one of the most exciting areas in modern manufacturing - that of additive manufacturing. Good show.

Hobbes · September 15, 2011, 10:51:35 AM

I've finished the design of the engine nozzle, the next step is to combine 9 nozzles into a single part (mainly to save money).

frank2056 · September 15, 2011, 04:19:04 PM

Harro,
That plate doesn't look like part of the model, just printer support. Why not replace it with a 3 x 3 grid? It would be a lot less material. Or you could cut out the back plate - like a honeycomb.

Frank

Hobbes · September 16, 2011, 02:15:48 AM

Hi Frank,

that plate is a first attempt, to see if the model is accepted by Shapeways. I ran into some trouble with the rocket nozzles; I ended up with so many vertices that AC3D started to run out of memory and crash. So I've simplified the nozzle in stages, then did this design to see if a model with 9 nozzles was within the limits.

I want to replace the disk with the actual bottom plate as seen here:

That's going to be a nice puzzle to figure out from photos...

Hobbes · March 31, 2013, 12:57:57 PM

I finally got round to picking this up again.

http://www.shapeways.com/model/1005168/falcon-9-large-payload-fairing.html

The top and bottom fairing, now in 1 part:

http://www.shapeways.com/model/1004887/falcon-9-engine-cluster.html
I've added some details to the engines:

philp · March 31, 2013, 01:49:29 PM

Brilliant stuff.

I have no skills on the computer besides typing (and even that can be a challenge at times).

Would love to learn how to draw (for decals) and this 3D stuff would be nice for a 72nd Minuteman I would like to make. Though, if I can get a lath, I might be able to just turn one like I had a guy do for my 1/144th scale versions I did for the Hill Aerospace Museum.

Hobbes · April 06, 2013, 06:38:58 AM

More parts:

The real thing:

philp · April 06, 2013, 10:40:54 AM

Looking good, can't wait to see the finished parts and build.

Hobbes · April 06, 2013, 10:49:32 AM

I ordered the first set of parts today, and an hour later on another forum I got a comment pointing out a big problem: you can't paint the engines like this. So it's back to the drawing board...

wuzak · April 06, 2013, 07:13:57 PM

Quote from: Hobbes on April 06, 2013, 10:49:32 AM
I ordered the first set of parts today, and an hour later on another forum I got a comment pointing out a big problem: you can't paint the engines like this. So it's back to the drawing board...

What are the restrictions on printing?

A guy at work has a 3d printer at home and he says it has limitations as to the shapes you can build. I guess if you are using a professional printing service that is less of an issue.

Hobbes · April 07, 2013, 01:25:17 AM

The restrictions depend on the material:
http://www.shapeways.com/materials/material-options

For each material there's a minimum and maximum size, minimum wall thickness and smallest detail size.

Home printers extrude a thin wire of plastic which has to be supported, so you can't create large overhangs. Shapeways' printers (at least for WSF) print by depositing a layer of fine powder on the entire printable area, then fusing only the powder that needs to be part of the model, so overhangs aren't a problem there.

Hobbes · April 15, 2013, 10:58:51 AM

I received my first printed parts today!

Engines:

The engines were made in Shapeways' highest resolution material, Frosted Ultra Detail. The result is fantastic. I did find a limit: the small tubes next to each rocket nozzle were hollow in my drawing, but came out solid. A similar small opening at the top of each nozzle contains some liquid goop, presumably the basic material they use for printing. The tube is too narrow to drain the excess.

Bottom of the first stage (this goes on top of the engines)

The other parts were in 'White Strong and Flexible Polished', a stronger, but coarser material. These will need some PSR.

nose cone:

Two halves connected by sprue

engine fairings (4 of them, linked via sprue to create a single printable part):

NARSES2 · April 16, 2013, 07:40:40 AM

Fantastic Harro