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Full Version: Plastic (or Aluminum as you want) case for NP-25
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Hi all,

I've received the free NP-25 from Chris Chung weeks before. Many thanks to Chris!
Then I found it was a little bit awkward to use NP 25 since it's only a PCB. So I decided to make a case for it. And this is the result! The case was machined by CNC with sloping surface on the edge and thus fits quite well in hand. The assembly is also simple: Just push the NP-25 PCB into the case. I make it tight @25℃, which means under most condition it's tight enough.

[attachment=2960]

[attachment=2961]

And now I'd like to sell this simple but useful accessory to the NP-25 users. Here are the prices:

Plastic case: $12
Aluminum case with surface treatment (anodized, black color): $20

Shipping cost: Don't know now. But since NP 25 can be shipped at such a low price ($8 world wide), I believe I could figure out a cheap shipping way...
Wow, that be nice.

I was (someday in the far distant future) looking to put mine in an HP25 stand alone battery pack charger housing (it just barely fits).

Clearly, yours is better.

Put me down for an aluminum one, thanx !!
Quite nice! Smile But were will we put the overlays?

d:-?
(12-16-2015 04:33 PM)walter b Wrote: [ -> ]Quite nice! Smile But were will we put the overlays?

d:-?

The original overlay was printed on the NP-25's PCB. The space is quite limited while NP-25 can emulate multiple models. (HP 21, HP 25C and HP 33C) Even though, Chris managed to squeezed into quite a lot nomenclatures.

If we want a customized overlay for each ROM, then the overlay should be switchable, which may require the HP-41 series design. I can make the front edge taller to hold a new overlay. Thanks Walter, I will consider the design. Maybe the new design will be adopted after I customize the overlays.
(12-16-2015 04:48 PM)Waon Shinyoe Wrote: [ -> ]
(12-16-2015 04:33 PM)walter b Wrote: [ -> ]Quite nice! Smile But were will we put the overlays?

d:-?

The original overlay was printed on the NP-25's PCB. The space is quite limited while NP-25 can emulate multiple models. (HP 21, HP 25C and HP 33C) Even though, Chris managed to squeezed into quite a lot nomenclatures.

If we want a customized overlay for each ROM, then the overlay should be switchable, which may require the HP-41 series design. I can make the front edge taller to hold a new overlay. Thanks Walter, I will consider the design. Maybe the new design will be adopted after I customize the overlays.


Good news!
Once redesigned to accept overlays I will get an aluminium one.

Thank you.
(12-16-2015 07:52 PM)Massimo Gnerucci Wrote: [ -> ]
(12-16-2015 04:48 PM)Waon Shinyoe Wrote: [ -> ]The original overlay was printed on the NP-25's PCB. The space is quite limited while NP-25 can emulate multiple models. (HP 21, HP 25C and HP 33C) Even though, Chris managed to squeezed into quite a lot nomenclatures.

If we want a customized overlay for each ROM, then the overlay should be switchable, which may require the HP-41 series design. I can make the front edge taller to hold a new overlay. Thanks Walter, I will consider the design. Maybe the new design will be adopted after I customize the overlays.


Good news!
Once redesigned to accept overlays I will get an aluminium one.

Thank you.

I may be late to the party but what do I need to do to get a NP-25 in the first place ?

François
(12-16-2015 08:20 PM)Francois Lanciault Wrote: [ -> ]I may be late to the party but what do I need to do to get a NP-25 in the first place ?

François

Have a look here François! Wink
(12-16-2015 07:52 PM)Massimo Gnerucci Wrote: [ -> ]Once redesigned to accept overlays I will get an aluminium one.

+1 !
(12-16-2015 04:05 PM)Waon Shinyoe Wrote: [ -> ]I've received the free NP-25 from Chris Chung weeks before. Many thanks to Chris!
Then I found it was a little bit awkward to use NP 25 since it's only a PCB. So I decided to make a case for it. And this is the result! The case was machined by CNC with sloping surface on the edge and thus fits quite well in hand. The assembly is also simple: Just push the NP-25 PCB into the case. I make it tight @25℃, which means under most condition it's tight enough.

Somehow the project look so much better w/ your case. Must be the lighting when you took the photo. Smile

Did you use stl file for CNC? I recently acquire a 3D printer. It's also the reason why there is no NP-41 updates, been playing w/ 3D stuffs. So a brief update until I put something on the NP-41 thread. I got new PCBs and hot air station. Managed to toast another processor (again!), did another one, w/ the charge pump issue fixed, the contrast is amazing good for a 6MUX LCD. Anyway, I will post photo on the NP-41 thread.
(12-16-2015 09:28 PM)Chris Chung Wrote: [ -> ]Did you use stl file for CNC?

If you'd like to share the .stl file I can make the case available on Shapeways.

Dave
Overlays for switching models is all the rage.

See Walter's work already done in this topic:

http://www.hpmuseum.org/forum/thread-303...l#pid31797
(12-16-2015 07:52 PM)Massimo Gnerucci Wrote: [ -> ]Good news!
Once redesigned to accept overlays I will get an aluminium one.

Thank you.

+1 as well.

I like your succinct replies Massimo. And you always beat me....
(12-17-2015 12:46 AM)rprosperi Wrote: [ -> ]I like your succinct replies Massimo. And you always beat me....

Thanks Bob, however I wasn't aware there was a race at all... ;)

And you were the first to reply to Monte's post, damn! :) :) :)
@WAON

A reminder.. cannot see how the PCB sits on top of the sunken base. Your NP25 was assembled without cutting short the DIP ICs. Instead I had raised them a bit so that their pins is not protruding through the back side (or front). So your build is thicker where the back side IC was.

Not sure how it will affect your design and how it fits other units. Please check original thread there are many photos on the older build units.
One plastic please.

BEST!
SlideRule
I'd like one plastic case too please!

Nigel (UK)
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