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Removing the back labels to HP classic series calculators

Posted by Mark Hoskins on 10 Nov 2002, 11:53 p.m.

Here is a method to removing the back label to the Classic HP 35,45,55,65,67 and 80. If followed carefully you should be able to replace them with near perfect appearance. This approach has worked well for me.

Step 1 Your tools

a) Get a very sharp Exacto knife with a crescent blade (curved in a semi circle). Do not use the very pointed blade because it can cut the label. Have the blade mounted to a nice big handle. b) Get a hairdryer just for this purpose. They are $3 at the Goodwill or any secondhand store. I use a 1600 BTU rated standard sized hairdryer. Use it on high unless it is the type that generates a very strong flow. You want a steady fairly fast air flow but not too hot so that it melts the back battery plate of the calculator (not fun at all).

Step 2 Hand-towel Wrap

Remove any batteries from the calc and replace the door to help seal the calculator from the hot air. Sit down and wrap the calc in a hand towel, except for the label, take a deep breath (really deep if it’s an HP-65). Place the calc label up with the upper portion wrapped in a doubled over towel. Place everything on your legs as you sit on a chair. Slightly overlap (1/4”) the top of the label with the towel so the hot air will not partially melt the case or back door.

Step 3 Turn on the Heat

Turn on the hairdryer and aim it away from the battery compartment. Move it back and forth to evenly heat the label. Use the tips of your fingers on a quick touch across the label to feel the heat of the label build up. Hold the dryer about 2-2.5 inches above the label and move it back and forth to evenly heat up the label surface. Heat it depending on how you feel the label’s heat, about 30-60 seconds.

Step 4 Lower left label corner

It is not clear why, but the lower left corner seems to be the best and most “pull-able” spot on the label to start the removal. Once in a blue moon the lower right also works. In a ticking motion, use the curved Exacto knife to lift up enough (about 3/16 inch) to pull with your fingers. Just before pulling drop the hairdryer like a hot potato. Concentrate on pulling up on the label at first, then pull more in tension evenly after the left edge rises (not just an upward motion). The label will curl slightly, no problem the hard part is over.

Step 5 Label smoothing

Take a piece of the backing of the printer labels that is smooth and gently push the sticky side of the HP calculator label onto it. Overlap the paper part by about ˝ inch. With you fingers generally straighten the edges and the curved part. Ideally you want to have a slight outward bend to the top of the label when finished. Get a smooth bottom spoon and place the HP label face down on your kitchen counter. Rub the paper side of the label and back of the label with the spoon (spoon rounded bottom touching the paper). I tried a plastic spoon and that worked well recently.

Start with the edges and flatten them then work your way into the center of the label. It is amazing how this flattens it all out. Experiment with one or two pieces of paper on the kitchen counter to see if that helps. It appears best to have the Hp label printing touching the kitchen counter. Make sure the counter is very smooth and clean before lettingthe label touch it.

Step 6 Resetting the label

Peel back the paper to reveal the sticky side of the HP label. Carefully clean the back of the calculator; leave no residue of the glue that may have stayed on the calculator. Align the TOP OF THE HP LABEL to reset it. Aligning the left side does not always work well and misalignments have happened to me.

That is how I remove these labels, if anyone has a better way I’d love to know. There is an HP collector in Germany who has another method he says is failsafe. He would have told me how if I won his bid, but I missed it. He said it took 3 hours, so that implies to me that he soaked it in some solvent. That may be possible if you have a very shallow dish that only the label would be immersed.

Any comments or other approaches are gladly received.

Best Regards,
Mark Hoskins


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