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38E disassembly - Printable Version

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38E disassembly - Kelvinretro - 05-10-2024 04:50 PM

Hello, I have a HP38e and requires disassembly for repair. After removing the two screws next to the battery like to know how do I remove the opposite side without breaking.
I thank anyone who can help me.


RE: 38E disassembly - ChrisKino - 05-12-2024 02:37 PM

Hi Kelvinretro,

Look here: https://www.hpmuseum.org/forum/thread-837.html?highlight=disassembly

Chris


RE: 38E disassembly - AndiGer - 05-12-2024 06:33 PM

… and you have to push and pull with your whole force if you follow the first link in the link … but it works - my experience
Andi


RE: 38E disassembly - teenix - 05-12-2024 10:48 PM

There is a method here on page 59 of the PDF.

cheers

Tony


RE: 38E disassembly - ChrisKino - 05-13-2024 07:29 AM

I found it on page 60 and 61. Wink

BTW, thanks for all of your amazing work Teenix!!

Chris


RE: 38E disassembly - BillBee - 05-13-2024 05:10 PM

The "crack" when the lower case hook releases is quite the alarming noise. It sounds worse than it is.

-Bill


RE: 38E disassembly - teenix - 05-13-2024 10:41 PM

Be careful pressing the sides of the top case inwards. This case design is thinner and less durable than earlier Classic models and can crack almost the full length of the calculator.

Also, be careful when removing the CPU/Keyboard. The six plastic "latches" holding the assembly in position can also crack or break off.

On re-assembly, there are 4 plastic alignment posts inside the top case half - about 2mm in diameter. These can also break off if the keyboard assembly is not lined up properly and "forced" into position - especially the two towards the display window which fit into 2 small holes.

cheers

Tony


RE: 38E disassembly - Matt Agajanian - 05-14-2024 04:45 AM

Just a thought…

I’m wondering if the Spike/Spice series was never intended to facilitate repair since these preceding post illustrate how delicate the E/C series is designed/assembled.


RE: 38E disassembly - Maximilian Hohmann - 05-14-2024 09:28 AM

Hello!

(05-14-2024 04:45 AM)Matt Agajanian Wrote:  Just a thought…

I’m wondering if the Spike/Spice series was never intended to facilitate repair since these preceding post illustrate how delicate the E/C series is designed/assembled.

In one of the many "Spice repair" threads someone mentioned a special tool that was available from HP for opening the cases of these calculators. This and also the solderless assembly could indicate that Spices were considered to be repairable by HP.

For me the major problem is the cheap plastic they used for these cases. It was brittle when it was new and it is very very brittle now, 40 years later. The older they get the more they crack and break during repair attempts.

Regards
Max


RE: 38E disassembly - Mike T. - 05-14-2024 10:25 AM

(05-14-2024 09:28 AM)Maximilian Hohmann Wrote:  For me the major problem is the cheap plastic they used for these cases. It was brittle when it was new and it is very very brittle now, 40 years later. The older they get the more they crack and break during repair attempts.

If I remember correctly HP used to make a big thing about the plastic they used as it was supposedly the same as the ABS plastic used in crash helmets at the time. I remember that my own HP33C acquired a small chip on one corner as a result of being accidentally dropped two floors onto a concrete slab, it was in its soft case which I suspect helped, but when I was able to retrieve it I was never the less hugely relieved to find it intact and still working! I didn't expect either, particularly some other items were scattered about in bits having not survived the unexpected drop, and I only noticed the chip a couple of days later.

However, I suspect that over time the plastic (whether ABS or not) will have become much more brittle, and would not try to opening any of mine unless I absolutely had to do so. You could argue that using what were arguably cost saving measures like the clip fit and solderless construction was rather short sighted but I doubt the engineers really expected those machines to still be working (never mind in use) almost 45 years later..


RE: 38E disassembly - Geoff Quickfall - 05-14-2024 11:13 PM

Check out this post also:

https://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/articles.cgi?read=925

Geoff