Post Reply 
HP-28S battery compartment rubber "seal"
01-18-2014, 09:44 PM
Post: #1
HP-28S battery compartment rubber "seal"
I acquired a HP-28S and found a mostly loose piece of rubber in the upper battery compartment. It's rectangular about 1x1.2mm in cross-section and several cms long. It seems to emerge from the partitioning between the upper and lower battery compartment about one battery length from the edge of the calculator. When a battery is inserted it is very hard to get it out again due to the friction of the rubber. I had to "knock" the calc on my knee to eventually get it out.

Is this piece of rubber supposed to be there, has it come loose and is supposed to belong elsewhere or might it be a hack to prevent the batteries from banging away the flimsy door?

Thanks for any insights!
Find all posts by this user
Quote this message in a reply
01-18-2014, 10:35 PM
Post: #2
RE: HP-28S battery compartment rubber "seal"
(01-18-2014 09:44 PM)Siegfried Wrote:  Is this piece of rubber supposed to be there, has it come loose and is supposed to belong elsewhere or might it be a hack to prevent the batteries from banging away the flimsy door?

Thanks for any insights!
The "rubber" string was supposed to be there (not all models), and was meant to reduce battery rattling, IIRC.

Slightly OT: The original Clamshell battery door and surrounding was unnecessarily complicated and easliy damaged due to heavy spring forces and weak plastic surroundings.

The latest incarnation with "backdoor" was the most important update to the clamshell series.

-- Ray
Find all posts by this user
Quote this message in a reply
01-18-2014, 10:37 PM
Post: #3
RE: HP-28S battery compartment rubber "seal"
Any idea on how to properly arrange batteries and rubber inside the compartment to take advantage of reduced rattling / less proneness to damage and still being able to remove the batteries without undue force?

(OT: Thanks for the nice greetings on the printer ;-))
Find all posts by this user
Quote this message in a reply
01-18-2014, 11:09 PM
Post: #4
RE: HP-28S battery compartment rubber "seal"
(01-18-2014 10:35 PM)Raymond Del Tondo Wrote:  Slightly OT: The original Clamshell battery door and surrounding was unnecessarily complicated and easliy damaged due to heavy spring forces and weak plastic surroundings.

The latest incarnation with "backdoor" was the most important update to the clamshell series.
We found out about that "mis-design" years ago when my girlfriend's HP-19B started to need a tape to stay closed....

I picked up a back-door version in the meantime but I suppose there is no back-door HP-28?
Find all posts by this user
Quote this message in a reply
01-18-2014, 11:32 PM
Post: #5
RE: HP-28S battery compartment rubber "seal"
(01-18-2014 11:09 PM)Siegfried Wrote:  I picked up a back-door version in the meantime but I suppose there is no back-door HP-28?
Unfortunately not, but maybe one could create a Frankencalc using a "backdoor" 19BII case, and implant 28S electronics inside.

(OT: Hope you like the printer:-)

-- Ray
Find all posts by this user
Quote this message in a reply
Post Reply 




User(s) browsing this thread: 1 Guest(s)