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HP Forum Archive 21

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3D-printed calculator parts?
Message #1 Posted by John Ioannidis on 16 May 2013, 2:18 a.m.

Before I go off and design them myself, has anyone designed spare parts that commonly fail, for printing on a 3D printer? Things like back doors for classics and peripherals, battery/door combos for woodstocks, HP41 battery holders, and so on? I haven't seen anything on either thingiverse or shapeways.

Regards,

/ji

      
Re: 3D-printed calculator parts?
Message #2 Posted by Frank Boehm (Germany) on 16 May 2013, 5:20 a.m.,
in response to message #1 by John Ioannidis

I fear that this will not work - the most common parts to fail have failed due to physical stress. 3D-printed parts look "OK", but are very weak due to the layered production process.
3D CNC'ed parts will probably work, but require a much more expensive 3D CNC machine...

            
Re: 3D-printed calculator parts?
Message #3 Posted by Jean-Michel on 16 May 2013, 5:34 a.m.,
in response to message #2 by Frank Boehm (Germany)

Hello
There are now also metallic 3D printed parts available, but the price is quite high. I don't know if it's worth the price compared to spare parts found on an auction site.
Cheers

                  
Re: 3D-printed calculator parts?
Message #4 Posted by Frank Boehm (Germany) on 16 May 2013, 2:00 p.m.,
in response to message #3 by Jean-Michel

Of course there are different types of 3D-printers (I think they have already created cell tissues with a 3D-printer), but in general the "functional" parts are failing, e.g. snap-in parts, screwposts, which need a certain "softness" and "flexibility", but also strength. ABS or polycarbonate are the preferred plastic types, metal will not really work for this type of application.

      
Re: 3D-printed calculator parts?
Message #5 Posted by Bruce Larrabee on 16 May 2013, 7:35 a.m.,
in response to message #1 by John Ioannidis

3D printing technology is constantly improving but in general I believe what has been said is currently accurate. If for example a 3D printing process becomes available that will produce for example a battery holder for the HP41 series for under $20.00 USD I hope someone will announce it here as that would be a break through.

            
Re: 3D-printed calculator parts?
Message #6 Posted by John Ioannidis on 16 May 2013, 2:51 p.m.,
in response to message #5 by Bruce Larrabee

I'm perfectly familiar with the limitations of various 3D printing technologies. I was asking if someone had models, not reasons why I shouldn't do it :)

                  
Re: 3D-printed calculator parts?
Message #7 Posted by Diego Diaz on 16 May 2013, 5:26 p.m.,
in response to message #6 by John Ioannidis

Hi,

Years ago I built the 3D model (just the ´model' not the part) for the HP-41 module shells. However and although this particular part is not bearing a big mechanical stress, it is mostly useless without the connector and therefore it was just a design exercise more than a real production project.

Cheers.

Diego.

                        
Re: 3D-printed calculator parts?
Message #8 Posted by John Ioannidis on 16 May 2013, 7:36 p.m.,
in response to message #7 by Diego Diaz

Pretty.

It would still be useful if you have, say, an old memory module that you want to repurpose as a connector, but the stuff you want to connect to it won't fit in the original tiny case. I've sacrificed a printer cable to do this in the past.

Can you send me the source for that design please? Or just put it on thingiverse?

Thanks.

                              
Re: 3D-printed calculator parts?
Message #9 Posted by Diego Diaz on 17 May 2013, 1:24 a.m.,
in response to message #8 by John Ioannidis

Hi John,

Yes for sure, I'll gladly send you the source file (Sketch-up).

Please let me know your e-mail address or drop me a line to: "clonix41(at)gmail(dot)com".

All the best from Caribbean.

Diego.

Edited: 17 May 2013, 1:24 a.m.

      
Re: 3D-printed calculator parts?
Message #10 Posted by Harald on 16 May 2013, 9:39 p.m.,
in response to message #1 by John Ioannidis

I have thought about this too. At work we did get a couple of 3d printed parts made. And I have to disagree with the others. The quality is really good. I had my doubts about some components as well, especially a few "snap on" parts. But the material is much more flexible and durable than I thought.

            
Re: 3D-printed calculator parts?
Message #11 Posted by Matthew Richards on 17 May 2013, 3:13 p.m.,
in response to message #10 by Harald

I agree with Harald. A coworker was learning to use a Dimension Elite 1200 that uses ABSplus thermoplastic. The printer manufacture claims the printed parts are "mechanically strong and stable over time" and ABSplus is "40% stronger than standard ABS." He reverse engineered and printed a replacement switch housing for his scooter. The part worked perfectly, after some iterative design, in a stressful environment that is probably more stressful than a calculator cover. His iterative design process was due to his initial attempt at strengthening the part and learning that he had to make a trade off between space and strength (probably the reason for the original part design).

http://www.protoz.com/images/ABSplus.pdf

                  
Re: 3D-printed calculator parts?
Message #12 Posted by Ian Phillips on 17 May 2013, 4:45 p.m.,
in response to message #11 by Matthew Richards

The link below is to a battery holder for the HP41 series that was made by SLA recently.

I cannot claim any credit, I dont have a 3D printer or the software to create the file (I dont have the skills to do it either) but a poster to this group (who has fully modelled a 41) sent me the file freely. One of my friends has SLA equipment at his place of work and he had the holder printed for me. I used battery springs etc from my scrapbox so now have a second functional 41CV.

I have to thank Jean-Michel Lecointre for the time he spent creating the 3D model and allowing to use it.

https://dl.dropboxusercontent.com/u/71301032/Small%20HP41%20Battery%20Holder%20by%20SLA.jpg

Ian Phillips

      
Re: 3D-printed calculator parts?
Message #13 Posted by aj04062 on 17 May 2013, 4:37 p.m.,
in response to message #1 by John Ioannidis

I have modeled both versions of the classic battery door latch. I've also modeled the Spice battery door. While the latches seemed to work okay, the door needed additional modeling work to get the fit correct.

With the 3-D printer I was using, I still had to file the latches a little with a nail file to fit nice.

I agree, technology is advancing and there is no reason that in due course we should be able to make good parts for a reasonable price.

      
Re: 3D-printed calculator parts?
Message #14 Posted by Bruce Larrabee on 24 May 2013, 12:32 p.m.,
in response to message #1 by John Ioannidis

Well I stand corrected. The 3D printer technology must be moving alone more rapidly than I had thought. (And I read two articles about the state of this technology within the last 30 days. One was in Scientific American and I can't at the moment recall where I read the other.)

To anyone with access to these high quality 3D printers that would like to try this I would be interested in providing the 3D model in exchange for a couple of the resulting cases or whatever you decide you want to do.


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