Pioneer Creaking

[Neil]

I've built up a collection of pioneer calcs. I've noticed that with a few of them, I can press the 2 case halves slightly closer together with my 2 fingers going around the edges of the calc, at some particular spots, with a consequent creaking sound when I press, or pinch together, and then release. On one of my calcs, there is even creaking when I press on one of the keys nearest the lefthand side, and this is due to the 2 case halves being able to move against each other at that point. I'm just wondering if this could mean that the calcs with this creaking may end up failing earlier than those where the 2 case halves are completely fixed, with no movement? This question is directed at the guys who have experience of opening and repairing pioneers.

[Eric Smith]

Sounds like you're talking about Clamshells rather tha Pioneers? E.g., 18C, 19B, 19BII, 28C, 28S?

[Neil]

Hi Eric,

No, I definitely mean Pioneers eg 17bii, 14b, 27s etc. If you take a look at a pioneer, you can see that there is a seam all the way around the sides. On a few of my calcs, there is some flexing at the seam when trying to pinch both calc halves together, with a consequent creak. On other calcs, there is no flexing at all. They are solid. My guess is that this flexing is nothing, it will never cause any keys to fail prematurely, but I was curious enough to ask the question.

[Eric Smith]

I misinterpreted what you said about pressing together the two case halves. Also, it is common for Clamshells to be a bit creaky.

[Karl Schneider]

Neil --

I have two calc's made in Singapore during 1993 -- an HP-17BII (Pioneer-series) and an HP-48G ("stretch Pioneer"). Both of them creak in the same fashion, but have yet to cause me any problems.

-- KS

Edited: 19 Mar 2006, 12:35 a.m.

[Neil]

Hi Karl,

Did you get your calcs in the early 90's (1993) and have you used them regularly ever since? If so, then that's certainly evidence that the creaking and flexing is a non-issue.

[Randy]

The creaking is most likely caused by several locking pins that extend from the front half into the back half. The back case has molded tapered sockets, I suspect the idea mechanically was for the pin to wedge tightly into socket helping to the hold the edges of the case together. In practice, probably due to material shrinkage once molded, its a less than perfect way to join the halves.

With the help of the Museum's 42S photo, the location of the pins are circled in white.

[Neil]

Randy,

Thanks for the detailed info. So does this basically mean that the whole keyboard assembly is not affected in any way by the case halves being slightly loose / creaky?

[Randy]

I see no reason why it would bother the calculator in any way.

Also, FWIW, *very early* Pioneers did not have the pins, they used a scheme like that later used on 48's - bent metal tabs and small plastic tabs that are supposed to interlock. IMO, less than perfect in practice as creaky 48's are pretty common.