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HP Forum Archive 06

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HP71B - #$%!!#!$@ screwed
Message #1 Posted by doug on 8 Nov 2001, 8:12 p.m.

Could anyone on this planet point me to the device that can be used to remove the #$%!!#!$@ screws that hold an HP71B together? I have spent a small fortune on every type of device that has been suggested to include security torx. Thanks, Doug

      
Re: HP71B - #$%!!#!$@ screwed
Message #2 Posted by Dan Lamb on 9 Nov 2001, 12:59 a.m.,
in response to message #1 by doug

Sometimes a small allen wrench, the ball end type, have worked for me. I have used them on my 71b and radar detector etc... It is not a perfect fit but it can work.

Good luck

Dan

      
Re: HP71B - #$%!!#!$@ screwed
Message #3 Posted by Michael Meyer, M.D. on 9 Nov 2001, 1:36 a.m.,
in response to message #1 by doug

Doug,

The tool you're looking for is a T-7 Torx screwdriver. You should be able to find a set of smaller Torx drivers in a large hardware store or perhaps an electronics shop.

Michael

            
Re: HP71B - #$%!!#!$@ screwed
Message #4 Posted by Julián Miranda on 9 Nov 2001, 10:34 a.m.,
in response to message #3 by Michael Meyer, M.D.

I took my 71 to an electronic shop and they found the suitable torx screwdriver. I paid around $4.00. I havent open it yet but the screwdriver fit perfect and loosen the screws that can be easily accesed (battery and card reader).

      
Re: HP71B - #$%!!#!$@ screwed
Message #5 Posted by Tony Duell (UK) on 9 Nov 2001, 1:49 p.m.,
in response to message #1 by doug

The correct tool (and the one that I've used to take my 71s apart) is a TX-6 Torx driver. They're available both as the 'L' shaped variety (looks like an Allen hex key) and as a tool with a screwdriver-like handle. On older HP71s (with the metal backplate) you have to undo the 2 tiny slothead screws nearest the edge of the machine (leave the one in the middle), and the 5 torx screws (under the 3 feet fixed to the machine, in the battery compartment and in the card reader compartment). Then carefully open the machine -- there's a flexible PCB at the 'number pad' side of the machine linking the CPU board in the top case to the memory/IO board in the bottom case. Don't damage it!

            
Re: HP71B - #$%!!#!$@ screwed--again!
Message #6 Posted by Michael Meyer, M.D. on 10 Nov 2001, 2:24 a.m.,
in response to message #5 by Tony Duell (UK)

Tony,

I wonder why there's a difference? (I hate to be wrong, but it happened, once, a long time ago, I think...) <grin>

I thought I might have had my torx's torked... I checked my set: "PCS ELECTRONIC SCREWDRIVER SET". It's definitely a T7 in my kit!!! I tried the T6, and it's too small... just spins in the #$%!!#!$@ screws.

Are there two different standards for Torx drivers... English/Metric?! I guess then, I'd recommend "try before buy"!

Michael

                  
Re: HP71B - #$%!!#!$@ screwed--again!
Message #7 Posted by Tony Duell (UK) on 11 Nov 2001, 4:56 p.m.,
in response to message #6 by Michael Meyer, M.D.

AFAIK there is only one standard for Torx drivers -- there are no English and Metric versions. Certainly I've never seen 'English' or 'Metric' Torx drivers, and I tend to read tool catalogues and frequent (good) tool shops. I am also sure that the Torx driver I use to take HP71s to bits is a TX6. Torx drivers smaller than that are made (I have them going down to TX3), but are hard to find. One thought, though. I've noticed that some cheaper-grade Torx drivers in the UK are undersized. For example, one of my printers is held together by what the service manual describes as TX-9 screws. For most of my sets of Torx drivers, that's correct. But for one cheap set, the TX9 is far too small, but the TX10 fits perfectly. So my advices is either to buy a good/expensive brand, or to try before you buy. Or to buy a set of all the sizes anyway -- you're sure to need them sooner or later (the latter probably explains the couple of hundred screwdriver-like tools in my toolbox :-))

                        
Torx screws
Message #8 Posted by Joe Panico on 12 Nov 2001, 1:28 p.m.,
in response to message #7 by Tony Duell (UK)

Mike & Tony,

Did HP switch during production? This is not an uncommon practice by manufactures, so some may be TX-7 while others are TX-6 (I think mine is 6).

Unrelated to the 71, General Motors did create its own Torx sizes to attach seatbelts and somethings else I can't remember on its cars. These are TX-45 & 50, so you're not likely to find one on a 71 (unless its crushed it). These are sold everywhere. Just passing along some trivia.

Joe

                              
Re: Torx screws
Message #9 Posted by Michael Meyer, M.D. on 12 Nov 2001, 3:59 p.m.,
in response to message #8 by Joe Panico

Joe,

I like your response. If true, it would explain the differences. If not, you'd be a great arbitrator!! If everyone else's seem to be T6's and the T7 I have fits all the HP-71's I have, my set is probably a strange size. It LOOKS like a quality set, with hardened bits, color coded handles, nice case, etc. And it wasn't cheap. Maybe they're even mislabeled. I once bought a Harry Chapin LP that has the right label, but the music is Seals and Croft. Bummer. BTW, I never could find a long enough Torx driver to take apart my 9114 drives, so I took a spare long handled phillips, cut off the tip, and used my dremel tool to make a six-sided Torx. Works perfectly! Never give up.

Michael

                                    
Re: Home made torx drivers & medical devices
Message #10 Posted by Frank on 13 Nov 2001, 6:23 p.m.,
in response to message #9 by Michael Meyer, M.D.

Just hope your are not operating on people with that home made stuff, too Michael! ;+} Frank (the Engineering kinda Dr.)

                                          
Re: Home made torx drivers & medical devices
Message #11 Posted by Michael Meyer, M.D. on 13 Nov 2001, 6:59 p.m.,
in response to message #10 by Frank

I guess then they'd REALLY be #$%!!#!$@ screwed....

No, I'm a psychiatrist. Makes sense. I like to figure out what's wrong and restore to working order. People, calcs, etc.

As far as home made medical devices.... I hadn't thought of that!!! You might be onto something here!!!

You know, the radiologists have said that they can take a picture of anything with a long enough needle and a strong enough arm. I always figured I could take apart anything with a big enough hammer....

I do agree that the right tool is best. I used to be a bicycle mechanic: head mechanic at a shop in Chicago for years. Occasionally, though, if you can't find what you need, you have to improvise. Hey, the airplane was invented by bicycle mechanics! (Maybe should have stuck with bikes....)

Michael

                                                
Why Torx
Message #12 Posted by Joe Panico on 14 Nov 2001, 1:37 p.m.,
in response to message #11 by Michael Meyer, M.D.

Micheal,

The last psychiatrist I spoke to was a stock broker. His reason: "I'm better at predicting stocks than predicting people." Anyway, Torx was developed for several reasons, chief among them that the design transmits greater turning force - drive to fastner - than other designs. Not a real necessity for a calculator, but the advantage in these applications is the reduced tendency for the drive to "cam-out" of the fastner. Ever round a Phillips? That's cam-out. Makes automatic assembly easier if cam-out is reduced. And ... there are both male and female drives/fastners. The screws on the 71 are examples of what most people see, a male drive Torx. Many automotive have both types in use, so, Mike, you may need to invest even more in tools.

Joe

                                                      
Re: Why Torx
Message #13 Posted by Michael Meyer, M.D. on 14 Nov 2001, 8:59 p.m.,
in response to message #12 by Joe Panico

Joe,

Oh, no, not again!! I think the money I used to owe to the "Snap-On" man was something like owing money to a bookie...

Actually, one of the most useful tool(s) I use in rebuilding calculators is a nice set of different sized hemostats; great for placing screws, reseating removeable wires, peeling back stickers, etc. etc. Very useful tools!

Hopefully I'm done rebuilding 9114 drives... I have two of them working well now...

I do appreciate your explanation for why Torx. But would a Phillips assembly machine really "cam-out" at the bottom of a deep, narrow hole? (Shallow ones, I can understand). I have to think part of it was to discourage disassembly by "non-qualified" personnel.

Most everything I've ever fixed had the statement, "No User Serviceable Parts Inside." Yeah. And the check's in the mail!

Be well, Michael

                                                            
Re: Why Torx
Message #14 Posted by Joe Panico on 15 Nov 2001, 12:09 p.m.,
in response to message #13 by Michael Meyer, M.D.

Mike,

My wife would rather I frequent dens of ill repute than hang out on the Snap-On truck. At the former I'm lost, at the latter I might buy a set of extender reach, swivel socket, tamper proof Torx sockets (set number, oops, I hear her footsteps)

At least tools are like old(er) HP calc's: they will serve you for years.

Joe

                                                                  
Re: Why Torx
Message #15 Posted by Michael Meyer, M.D. on 16 Nov 2001, 11:13 a.m.,
in response to message #14 by Joe Panico

Joe,

I couldn't agree more! In fact, I think our discussion goes directly, now, to the heart of another current thread: the death of HP calcs and quality product development.

Even when I was a starving college student, literally living in basement apartments (once in a condemned building), working 3 jobs to put myself through school at Northwestern, and existing on peanut butter and jelly and Ramen noodles, I refused to buy a cheap tool. I'd rather save for weeks and get a quality tool than one that would fail, costing more time, effort, and money in the long run.

I bought HP because of its quality, and to this day, I would rather spend more on a quality product. I don't think I'm completely alone in this, but apparently in the consumer minority. (Remember when quality cars gave way to cars like the Pinto, Chevette, and other "disposable" crap cars...) I was so disappointed when I bought an HP-720 series printer and the software never worked right and there were posts left and right about it, but HP kept denying any problems, and selling them like crazy.

I write with a Mont Blanc fountain pen because it's elegant, reliable, well designed, and actually saves me money many times over a pile of cheap pens. Other examples are endless. There is still a population of enlightened consumers that will pay more for quality products. I would rather spend the big bucks on a Windows upgrade that is SMALLER, has LESS bells and whistles, but has an efficient code that will run fast and well on my existing computer, instead of continuous upgrades that require endless expense of time and effort and hardware. But, I guess that's not how it's done in this quick-profit environment.

By the way, to relate this to my own profession: The World Health Organization reports that the top two causes of disability in the WORLD are now psychiatric; depression and anxiety disorders. YET, mental health care has been cut from 12% of the U.S. health care dollar to 3% in the last ten years. College graduate level therapists are reimbursed at almost the same rate as physicians, who've had three to six times the years of schooling. Nobody is going into training, and the medical schools can no longer draw top college graduates. Insurance companies make record profits... The solution? Faster and cheaper! More profit, less quality. Give lesser trained people the same job! Psychologists (who have not even attended medical school) will soon succeed in gaining the right to prescribe medications (after attending a couple of weekend seminars), as have optometrists, physician assistants, and nurse practitioners. I think in a few years, all you'll need to be a physician is a grade school biology class. Even the physicians in training, now, are limited in the number of hours they work... can't make it too hard, now!

HP is just following the rest of the world. Isn't it sad that people sometimes have to actually omit their educational history to even get some jobs these days (or they're over-qualified!!)

Sad. Now I know why I still love to use and collect HP calculators. Now I understand my love for these old products.

Someday, in the not too distant future, more people will ask, "What happened?! Why are there no resources available to treat my suicidal kid (wife, sibling, etc.) I thought you were just complaining, doctor!" There used to be six psychiatric hospitals here in Omaha. Now there are two, and they're always full. There's no substance abuse treatment available other than community houses (non-medical).

Anyway. I think there's a direct connection here. I still have all the quality tools I bought in college 25 years ago. But, I'm sounding like an old fart, now.

Michael


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