Spice calculator - glue?

[james summers]

Greetings All

I haven't done much with my HPs for the last 5 or so years (life getting in the way) but I have a couple of Spice machines which require the screw posts at the rear to be sorted along with cracked shells also at the rear (probably due to too long ordinary AA cells being used rather than shorter flat tops).

What are the Forum's thoughts on the best glue to use?

I've got some Tensol 12 used for gluing acrylics like Perspex - ingredients dichloromethane, methyl methacrylate and 2-phenoxyethanol - which I understand when used for Perspex softens the surfaces and then fuses them.

Or would E6000 as recommended in the HP 41 Repair book by The Calculator Store for attaching their '41 screw post replacements to the keyboard circuit board be good for the Spice plastic?

What glues have you had success with and what glues should be avoided?

[Maximilian Hohmann]

Hello!

(07-06-2022 06:52 PM)james summers Wrote:  What glues have you had success with and what glues should be avoided?

I think that the housing of the HP-30 / Spice series calculators is made from polystyrene (Polystyrol where I live). Therefore I would try the kind of glue that modelers use for plastic models (like the ones from "Airfix" for those who remember that long gone brand), e.g. "Revell Contacta".

Another glue that I often try first with unknown types of plastic is "UHU Allplast" (can be found on Amazon like the one above). You either get almost instant good bonding or no bonding at all, in the latter case it is easily removed without leaving traces.

Sometimes I also got an easy repair with a drop of superglue (cyanoacrylate). To some types of plastic it does not bond at all, like the one the little bottles are made from that it comes in, to others it sticks very well. Again, you won't damage anything by trying.

And what to avoid? If my assumption is correct and the housing is made from polystyrene then avoid any type of glue containing acetone, or pure acetone for cleaning. It dissolves polystyrene as quickly as hot tea dissolves sugarcubes...

Regards
Max

[james summers]

Thanks Max, I'll have a look at those, and keep away from acetone!

Yes, I remember Airfix, spent many a happy hour gluing myself to bits of planes in my youth!

Regards

James