Glue?

[KimH]

I have a couple of pieces I need to glue together on the 71B.

I know THOUGHT that regular Super-Glue (the obvious answer) had a tendency to attack both the circuitry and the PCBs - over time - if you are not very careful.

I was searching for a hint here on the Museum, but could not find anything.

Any hints are welcome.

EDIT - Thanks for the comments! I will give Cyanolite a try

[Maximilian Hohmann]

Hello!

(02-03-2021 06:55 PM)KimH Wrote:  I know that regular Super-Glue (the obvious answer) has a tendency to attack both the circuitry and the PCBs - over time - if you are not very careful.

Do you happen to have a source for that? It is the first time that I hear that superglue (i.e. cyanoacrylate) can have adverse effects on electronics. I have used it a lot on calculators and other electronic devices and have not yet noticed anything at all.

The Wikipedia article on Cyanoacrylate says (among other things): "Electronics -
Cyanoacrylates are used to assemble prototype electronics (used in wire wrap),..."

Regards
Max

[[kby]]

I don’t why this would be true either. It can melt the plastic and it tends to be hard to control. It also doesn’t bond that well, but can work adequately in many situations. It can be hard to get a good bond and only get it in the right places. Using an accelerant usually makes the bond better but can also be messier. But neither of these are long-term degradation issues.

(02-03-2021 07:14 PM)Maximilian Hohmann Wrote:  Hello!

(02-03-2021 06:55 PM)KimH Wrote:  I know that regular Super-Glue (the obvious answer) has a tendency to attack both the circuitry and the PCBs - over time - if you are not very careful.

Do you happen to have a source for that? It is the first time that I hear that superglue (i.e. cyanoacrylate) can have adverse effects on electronics. I have used it a lot on calculators and other electronic devices and have not yet noticed anything at all.

The Wikipedia article on Cyanoacrylate says (among other things): "Electronics -
Cyanoacrylates are used to assemble prototype electronics (used in wire wrap),..."

Regards
Max

[AndiGer]

E6000 once was recommended glue for HP-41 cases here

[Kostas Kritsilas]

(02-03-2021 06:55 PM)KimH Wrote:  I have a couple of pieces I need to glue together on the 71B.

I know THOUGHT that regular Super-Glue (the obvious answer) had a tendency to attack both the circuitry and the PCBs - over time - if you are not very careful.

I was searching for a hint here on the Museum, but could not find anything.

Any hints are welcome.

EDIT - Thanks for the comments! I will give Cyanolite a try

KimH:

In the past I have had occasion to work for a couple of large electronics firms, in the factories that produced electronics ranging from consumer (PCs) to communications (Cellular Base Stations and Central Office Switches). All of them used cyanoacrylate (what you call Superglue) for tacking down modification wires (what is now called "bodge wires"). In all cases, the cyanoacrylate glue was tested for its effects on PCBs (solder mask, PCB traces, and gold plated connector fingers and connector pins) and found to be safe for use. I don't know what brand or concentration your "Superglue" is, but as a general rule, cyanoacrylate does NOT attack PCBs, even when accelerator is used. The electronics industry standard glue was Loctite (may have been type 631, but don't quote me on that). Note, this is not just a short term test; central office switches are normally in service for 25 years, and that type of life test was done on the Loctite cyanoacrylate glue, with and without accelerator.

[John Keith]

On a related but slightly off-topic note, one should be careful with silicone sealants and adhesives. Some silicones release acetic acid when they cure, which can corrode copper. Newer silicones which release ethanol while curing should not be a problem. If in doubt, check for a vinegar odor before using.

[[kby]]

While important to get it out long term (and it could be an issue for a large glob of silicone thst is only cured on the outside and slowly leaches out a small constant stream of acetic acid), the vinegar we soak in to clean corroded boards in is acetic acid. Is it the acid itself or the acid in conjunction with something else? I know there was the old prohibition about using acid-core flux solder on electronics (and the acid flux is, I’m fairly certain, a weak organic avid similar to vinegar). Copper alone should not be that vulnerable but some of the boards may use cheaper alloys that are more acid sensitive. But the issue is still there wrt the vinegar bath.-kby

(02-05-2021 06:17 PM)John Keith Wrote:  On a related but slightly off-topic note, one should be careful with silicone sealants and adhesives. Some silicones release acetic acid when they cure, which can corrode copper. Newer silicones which release ethanol while curing should not be a problem. If in doubt, check for a vinegar odor before using.