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HP-65 Card Spring - Printable Version

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HP-65 Card Spring - teenix - 10-26-2021 07:34 AM

Hi all,

I opened a HP-65 to do a gummy repair and one of the card side load springs was missing. One of those items that behaves like a grass hopper and then in the blink of an eye disappears into the atomic structure of anything around it.

I don't have any spares or any original material like that so I used some plastic from packaging for a tooth brush. Most items these days are packed on a cardboard backing with with formed clear plastic on top, so I guess just about anything like this will do. The only thing is that it can't be too think or it won't be flexible enough, or too thin or it will be too flexible.

The plastic I used was about 0.006" thick and is probably standard on a lot of packaging. I just cut and trimmed a piece of it to size by trial and error. It took a few goes, although it doesn't take much time to make one and the mouldings in the card casing hold it in place like the original spring.

cheers

Tony


RE: HP-65 Card Spring - Paul Dale - 10-26-2021 08:36 AM

Is there any risk of static build up on the plastic?
If so, does it risk card integrity?


RE: HP-65 Card Spring - teenix - 10-26-2021 09:08 AM

(10-26-2021 08:36 AM)Paul Dale Wrote:  Is there any risk of static build up on the plastic?
If so, does it risk card integrity?

The card itself rubs against the plastic moulding, nylon switch activation balls and roller as it passes through the reader so I would assume not. The spring part is very small and only has a point contact with the card. I'm no expert but I imagine there's probably more chance of passing a static charge from ones fingers to the card.

cheers

Tony


RE: HP-65 Card Spring - rprosperi - 10-26-2021 01:16 PM

Nice and simple solution Tony Great suggestion, I'd have never thought of that! Also, one toothbrush pkg. is a lifetime supply of card reader springs.


RE: HP-65 Card Spring - isanchez - 10-26-2021 01:27 PM

Well done! Thanks for sharing!

Regards


Ignacio


RE: HP-65 Card Spring - toml_12953 - 10-26-2021 01:49 PM

(10-26-2021 07:34 AM)teenix Wrote:  I don't have any spares or any original material like that so I used some plastic from packaging for a tooth brush. Most items these days are packed on a cardboard backing with with formed clear plastic on top, so I guess just about anything like this will do. The only thing is that it can't be too think or it won't be flexible enough, or too thin or it will be too flexible.

You win the MacGyver award!

MacGyver was an American TV show in which every week the hero would get out of almost impossible situations by cobbling together devices from whatever happened to be on hand.


RE: HP-65 Card Spring - jlw - 10-28-2021 02:12 AM

I found that the width of a magnetic card is just about right to replace those springs. You can sacrifice one blank card for the team, no? One card will make maybe 50 of those springs.

I did eventually find the spring I had lost.


RE: HP-65 Card Spring - albertofenini - 10-30-2021 10:04 AM

Brilliant, as always !!!!
take care


RE: HP-65 Card Spring - teenix - 11-29-2021 02:17 AM

Unbelievable, 4 weeks ago I lost one of the card reader guide springs and had to make a replacement. Today I dropped a wire pin and it bounced across the carpet somewhere and while looking for it I found the guide spring.

I didn't find the pin, but it was a good trade off :-)

cheers

Tony