Anyone ever fabricated replacement centrifugal switch contacts?

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jmarkwolf

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I inadvertently broke one of the copper leafs on one of the centrifugal switch contacts on a vintage 65 year old Delta 1/2hp drill press motor.

I'm wondering if it is worth considering refabricating the copper leafs complete with new contacts and hollow rivets, etc. I don't know the alloy, a source for the hollow rivets or the contacts, or method of accurately cutting and bending the thin metal foils, but I am quite adept in printed circuit board design and could redesign the entire assembly in FR4 PCB material without difficulty, once I were to get a handle on the afore mentioned items.

I hate to squander a perfectly good vintage motor for want of a centrifugal switch assembly.
 

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The copper leaves are probably spring temper phosphor bronze. The contacts would most likely be a silver alloy.
 
There are (at least were) replacment switches available. I have usually used W W Grainger, there are many electrical suppliers that had them. I have broken a few myself, always the phenolic portion though. Micarta is extremely brittle. And worked on motors that others have broken. It is a (not too) common repair for single phase motors. Then there are parts from motors that have had the majic smoke escape. Usually, there is some filing involved, but they can be finagaled. Mostly it is a matter of patience. Lots of it. . .

.
 
Sure you can fix it. Copper solders well so just repair/reinforce the support structure with brass or copper sheet, keeping the original contacts.
Good on you for wanting to save it, I wish more people would do it
 
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Be interested in where this goes. I was contemplating harvesting the contact points off a new generic switch to replace existing (pitted/eroded) switch points. The spring action was in good shape. I was told the little tungsten hockey pucks are silver brazed on their arms by a local motor/electric shop. He figured it would be better to preserve that joint & try & graft it onto the existing switch. Now whether that (silver solder / braze) was the switch he happened to be looking at or his guess or switches in general I cant say. Let us know how this turns out.
 
Worst case scenario is use external relay to switch the current.

A bit of rewire needed but leaves existing in place.



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There are solid state switches that can be installed to take the place of the mechanical one- Ulma doctor (Mike) did a video about it
 
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