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General control line discussion => Open Forum => Topic started by: Howard Rush on August 30, 2011, 02:04:00 AM

Title: 3-D Printer
Post by: Howard Rush on August 30, 2011, 02:04:00 AM
I know some folks who have a 3-D printer that's looking for things to print.  http://www.dimensionprinting.com/3d-printers/printing-productspecs1200series.aspx describes the machine.  It makes actual parts from 3-D CAD files.  It makes them out of ABS, not the gummy stuff these things used to use.  It can make parts that can't be machined otherwise.  Two examples are parts with internal hollow spaces and unassembleable assemblies such as chains with seamless links.  Parts are rather cheap for small runs.  What can you think of for this thing to make?
Title: Re: 3-D Printer
Post by: Douglas Ames on August 30, 2011, 04:26:37 AM
At that price I'm sure they are! The only things I could think of would be cowling or wheels pants.
Title: Re: 3-D Printer
Post by: Peter Nevai on August 30, 2011, 10:07:20 AM
Come on guys, show some imagination.

Adjustable lead out guides especially some that need unconventional configuration.
Tip weight Boxes
Tank restraints
Cowl attachments

Just about any item for the Semi Scale Stunter guys

This sort of stuff would be a boon to the electric guys for custom mounts and other odds and ends.

For the take apart guys this may also be a great thing.

It all boils down to cost.
Title: Re: 3-D Printer
Post by: Mark Scarborough on August 30, 2011, 12:24:12 PM
Howard, I can think of a couple things, simulated exhaust stacks ( for my bf 109 stunter) a spinner cone ( again, for the 109) canopy frames ( again 109) Landing gear simulated struts,
what kind of cost are they talking for something like a pair of struts. I can do the 3D modeling

Title: Re: 3-D Printer
Post by: Howard Rush on August 30, 2011, 02:08:29 PM
Something like five bucks.  You are the ideal candidate to take advantage of this technology.  The CAD model is the hard part. 
Title: Re: 3-D Printer
Post by: Mark Scarborough on August 30, 2011, 02:21:16 PM
Howard, I will work up a model this week. that sounds awesome! thanks
Title: Re: 3-D Printer
Post by: Mark Scarborough on August 30, 2011, 02:22:35 PM
Is this material suitable for a spinner do you think?
Title: Re: 3-D Printer
Post by: Steven Kientz on August 30, 2011, 02:25:59 PM
How about scale cockpits?

Steve
Title: Re: 3-D Printer
Post by: Howard Rush on August 30, 2011, 02:46:15 PM
Is this material suitable for a spinner do you think?

Probably.  I think the plastic spinners I've been using are ABS.  The material isn't isotropic: the Z axis may be weaker than the others.  I'd make the spinner axis the Z axis. 

You are the guy to ask about finishing this stuff.  The parts come out a little lumpy.   I presume finishing them to stunt standards would be akin to finishing ABS car parts.  How do you do that?
Title: Re: 3-D Printer
Post by: Howard Rush on August 30, 2011, 02:48:23 PM
How about scale cockpits?

There's the aforementioned lumpiness.  Can you make a 3D CAD model of it?
Title: Re: 3-D Printer
Post by: Mark Scarborough on August 30, 2011, 02:55:19 PM
On car parts, they are typically coated with a primer coat. I suppose it depends upon the actual depth of the lumpiness. I have in the past had moderate success with sanding ABS, but without trying one really wont know. I think my approach would be to create the model slightly undersized if critical, to allow for filler material on the surface, or if the material proves to be sand-able, then slightly over-sized to allow for material removal. Again, it would depend upon the size of the "lumpiness".
I think it the case of the exhaust stack, the lumpiness ( assuming its magnitude is minimal) would not be as much an issue.
I suppose the way to find out is to actually create a 3D model, and have something done , then I would be able to get a better feel for what we are looking at for finishing.
Catalyzed primers would be de' riguer for working on ABS, there are adhesion promoters for working on plastics that may be required, again, the specific material would dictate the approach.

you refer to CAD drawings, am I to then infer that a standard .dwg file will be suitable or would a .dxf file be more appropriate?
Title: Re: 3-D Printer
Post by: david smith on August 30, 2011, 03:30:45 PM
At my work we have one and judging by the stuff I have seen I would probably scuff it really good with some red scotch brite and use an automotive high build primer with 3 or 4 coats. The key is some sort of adhesion promoter and follow the instructions for it exactly.  The lumps Howard is talking about are the ridges from each layer of plastic that is put down to make the part.  They are usually pretty small and should be able to be filled with the primer. 

David
Title: Re: 3-D Printer
Post by: Howard Rush on August 30, 2011, 04:32:07 PM
Steps in the Z direction are .010".  Discuss file type with Emma (see your email).
Title: Re: 3-D Printer
Post by: Lauri Malila on August 31, 2011, 02:51:52 PM
 There is also rapid prototype machines that "print" the thing in a similar way, but from wax. I'd be more interested in that, it opens lots of new possibilities in investment casting. The traditional way to make the molds for wax injection requires quite heavy machinery.
 I think that at least the F2A flyers have allready found this technology. L