Due to the design, the centre pad of the three suffers from spark erosion every time it is switched, and consequently wears away.<\/p>\n\n\n\n
![\"\"](\"https:\/\/www.alphabeta.me.uk\/blog\/wp-content\/uploads\/2021\/12\/IMG_3198-2848x3797.jpg\")
<\/a><\/figure><\/li>![\"\"](\"https:\/\/www.alphabeta.me.uk\/blog\/wp-content\/uploads\/2021\/12\/IMG_3197-2848x3797.jpg\")
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<\/a><\/figure><\/li><\/ul><\/figure>\n\n\n\nMy first thought was to replace, but it seems that you cannot buy this part separately.
So… repair then, but the copper pads are not removable, it seems the plastic is cast in place around the pads.
In desperation, I considered the implausible… Is it possible to copper plate the center contact pad back to a functional thickness?<\/p>\n\n\n\nAssembling the parts needed for copper plating took a couple of days.
Hydrogen Peroxide, White Vinegar, some pure copper mesh.
Then following instructions as per this website<\/a>.<\/p>\n\n\n\n![\"\"](\"https:\/\/www.alphabeta.me.uk\/blog\/wp-content\/uploads\/2021\/12\/IMG_3196-2848x2136.jpg\")
<\/a><\/figure><\/li>![\"\"](\"https:\/\/www.alphabeta.me.uk\/blog\/wp-content\/uploads\/2021\/12\/IMG_3195-2848x3797.jpg\")
<\/a><\/figure><\/li>![\"\"](\"https:\/\/www.alphabeta.me.uk\/blog\/wp-content\/uploads\/2021\/12\/IMG_3205-2848x3797.jpg\")
<\/a><\/figure><\/li><\/ul><\/figure>\n\n\n\nAs can be seen from the last picture above, the experiment was a partial success!
copper was precipitated onto the pad(s), but I got glorious crystalline tree structures instead of an increase in thickness.
This was probably caused by the fact that I simply left it to run for 24 hours rather than constantly agitating the work in the solute.
The experiment was ended in any case by the 40 year old plastic cracking in two.
Fortunately, in the course of hunting down other items in the parts bin, I found yet another old smashed up LHS switchgear, which had a serviceable contact pad.
5 minutes with a soldering iron, and I had internals complete to fit into the repainted cases.<\/p>\n","protected":false},"excerpt":{"rendered":"Inspection of the internals shows that mostly, the wiring is OK, if a little bit stiff and brittle with age.The…<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,6],"tags":[],"_links":{"self":[{"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/posts\/1319"}],"collection":[{"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/comments?post=1319"}],"version-history":[{"count":3,"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/posts\/1319\/revisions"}],"predecessor-version":[{"id":1328,"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/posts\/1319\/revisions\/1328"}],"wp:attachment":[{"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/media?parent=1319"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/categories?post=1319"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.alphabeta.me.uk\/blog\/index.php\/wp-json\/wp\/v2\/tags?post=1319"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
![\"\"](\"https:\/\/www.alphabeta.me.uk\/blog\/wp-content\/uploads\/2021\/12\/IMG_3198-rotated.jpg\")
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