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Modern Reproduction Techniques
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Author:  Andy Nold [ Wed Jan 30, 2013 8:06 pm ]
Post subject:  Modern Reproduction Techniques

I thought a thread discussing various modern technologies that can be applied to part reproduction would be a good thing to start, so here is something I ran across today that I thought I would share with you engineering types.

Affordable Injection Molding Transforms Tinkerers Into Tycoons

http://www.protomold.com/

Author:  Dennis Storzek [ Thu Jan 31, 2013 2:36 pm ]
Post subject:  Re: Modern Reproduction Techniques

This is the same old blather these outfits always expound; note the statement, "moderately complex projects can still cost more than a car." I don't think they are talking about a fifty dollar beater, either. In reality, what these kinds of outfits sell is speed, not price, and we all know that speed usually comes at a premium. The real advantage these folks have with the inventor market is they will quote at all; most tool shops have been burned more than once by inventors and won't quote at all, or sky high if they do.

Author:  Andy Nold [ Thu Jan 31, 2013 5:41 pm ]
Post subject:  Re: Modern Reproduction Techniques

This is the foundry that I have been using for the Birney Brill 79E reproduction production project.

Western Foundries, Longmont CO

I will be talking to them in the next few weeks for the next round of parts. I think the consensus at the ARM Convention was spring cups. The pricing on patterns and castings beats my local foundry and they are easy to work with.

I would like to use this post as a guide for restoration resources. I welcome and encourage others to post too. I am interested if anyone has outsourced 3d printing for patterns and recommendations for places and techniques.

Author:  Terry Harper [ Thu Jan 31, 2013 6:47 pm ]
Post subject:  Re: Modern Reproduction Techniques

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Author:  Becky Morgan [ Fri Feb 01, 2013 2:33 pm ]
Post subject:  Re: Modern Reproduction Techniques

Printing tech is evolving very rapidly but somewhat behind the scenes. Last month there was a small news clip about the Army sending twelve trailers equipped with 3D printers into the field so small part stocking wouldn't be a problem. They weren't specific about what small parts for what armament, perhaps needless to say, but I do know that Purdue does have a working metal printer.

So far--so far--most of the home models use only styrene and print in a single color. Multi-color printing in other plastics is entirely possible; I've seen a commercial ABS printer. I'm not surprised that 3D printing is starting to make inroads; I'm surprised that it's taking so long.

Author:  Andy Nold [ Fri Feb 01, 2013 3:27 pm ]
Post subject:  Re: Modern Reproduction Techniques

I use AutoCAD Civil3d 2012 at work and I have had training in AutoCAD Inventor. The 3d printers are very interesting. I hope to model and print a bell cord hanger bracket soon to use for a pattern for brass casting.

Author:  crij [ Fri Feb 01, 2013 4:40 pm ]
Post subject:  Re: Modern Reproduction Techniques

We have been looking into 3D printing for prototyping here at work, there seems to be 4 basic technologies: in ascending price: (could be more hidden within research centers)

Extrusion: $500-$1000 - ABS plastic is melted and applied through a print head. I have seen up to 2 print heads (color or material strength)

Lithography: $2,000-$10,000 - uses a photo sensitive polymer, either a laser scans the current layer or a projector flashes an image of the layer. The UV light reacts with the polymer creating a solid layer. (monochrome, but multiple polymers available)

Binder: $100,000+ - liquid binder is sprayed over granular material, and the binder either reacts or dries and glues powder together. (color is usually within the binder and the non-reacted powder supports the part being created)

Sinter: $??? - laser melts layers of granular material, fusing it to the layer below it.

Image quality and strength increases as you go from cheap to expensive.

Rich C.

Author:  Terry Harper [ Fri Feb 01, 2013 10:59 pm ]
Post subject:  Re: Modern Reproduction Techniques

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Author:  Becky Morgan [ Sat Feb 02, 2013 2:39 pm ]
Post subject:  Re: Modern Reproduction Techniques

Nice! There'll always be a place for honest craftsmanship.

I can see how 3D printing will reduce the turnaround time on repairs, even if brass, bronze and steel aren't in the pipeline (so to speak) yet. This no longer available part broke, so scan it, "repair" the scan, print in styrene or whatever, use the print to make the mold, hit the foundry. Even so, someone is going to have to know how to pour the casting and do the final machining, not to mention that somebody will need to install and adjust it. It never will be just mashing keys :)

Author:  LVRR2095 [ Sat Feb 02, 2013 4:03 pm ]
Post subject:  Re: Modern Reproduction Techniques

Terry Harper wrote:
Dont forget the old ways! I made these patterns for bronze castings for an antique engine. Good old pine and a lathe.


Terry....where have you found a foundry that will work with loose patterns?

Keith

Author:  Terry Harper [ Mon Feb 04, 2013 12:31 am ]
Post subject:  Re: Modern Reproduction Techniques

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Author:  Dave [ Mon Feb 04, 2013 10:06 am ]
Post subject:  Re: Modern Reproduction Techniques

Nice hijack, but what can you tell us about the NEW practices? That's the point of this thread....m,ost of us old heads know more about old founding than we'd like, and how it can be frustrating and costly in terms of time which is getting shorter in supply for many of us on a daily basis.

3D printing might be expensive, but still could be cheaper than handcrafted patterns for a one-off part. And, unlike old school foundrywork, it is going to get much cheaper pretty rapidly, and the turnaround time?

So, in the not too far distant future, we wil be able to have that little bell rope bracket laser scanned, finagle a bit of shrinkage allowance and draft into the program, and print out in a half an hour a pattern that can be packed in sand and melt out when the brass is poured in. Of course, it will take many days of not weeks to get the people who melt and pour brass and pack patterns in sand to get around to it. And, you can instantly email the digital program to anybody else who needs a little bell rope bracket like yours across the world.

I find that astounding...and of very high value, relative to the monetary cost. Of course, I don't think the time and effort put in by either myself or volunteers is of no value. You can always earn more money.....if you have time.

dave

Author:  crij [ Mon Feb 04, 2013 4:00 pm ]
Post subject:  Re: Modern Reproduction Techniques

Quote:
So, in the not too far distant future, we wil be able to have that little bell rope bracket laser scanned, finagle a bit of shrinkage allowance and draft into the program, and print out in a half an hour a pattern that can be packed in sand and melt out when the brass is poured in. Of course, it will take many days of not weeks to get the people who melt and pour brass and pack patterns in sand to get around to it. And, you can instantly email the digital program to anybody else who needs a little bell rope bracket like yours across the world.


Dave,

We are already there. You don't even need the laser scanner, as there are programs out there that convert a group of photos to 3d models, all you have to do is add a few dimensions (add the shrinkage to your measured dimension) to the model and you now have a 3d file you can e-mail to someone with a 3D printer. They print it out, the foundry add gates & vents, covers it in mud (refractory cement) and pours the metal, the heat of the metal vaporizes the printed plastic model as it fills the cavity. Once the cement is broken off you now have a finished casting. If it was a machined part, after the solid model is created import it into a 3D drafting program, add some material to the machined surfaces and resave.

Rich C.

Author:  Dave [ Mon Feb 04, 2013 4:23 pm ]
Post subject:  Re: Modern Reproduction Techniques

Sure sounds more reasonable than spending hours on a cope-and-drag pattern to me. I would expect that as the cost per copy goes down, the volume necessary to make the process cost effective relative to old school patternmaking and use will also decline pretty dramatically.

dave

Author:  Terry Harper [ Mon Feb 04, 2013 5:49 pm ]
Post subject:  Re: Modern Reproduction Techniques

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