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Help needed on electromagnet repair

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jollydeere

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I appologize if I have hosted this in the wrong area. Old age has fogged my memory of formulas and other things.

I am restoring a 1940-50s vintage firehouse klaxon made by IBM. This si for my son who owns a small company custom building off-road firetrucks.

The electromaget which runs the klaxon is fried (open, not shorted). In this device a horseshoe shaped, 12vac electromagnet vibrates a small hammer into a metal sounding plate. The buzzing racket is transported out two megaphones to wake up the crew and send trucks down the road.

I need to rewind both legs of the horshoe magnet. The magnet is laminated like a transformer core. Here's what I have been able to determine:

12vac, 1.6 amps, 60 cy.
Legs of themagnet are 0.45-0.46 square
Length of wound coil on each side is approximaely 1.1" long
Outside thickness of the wound coils are approximately 0.85" and are square in profile.
Wire guage and lenth is presently unknown and is what I hope to determine.

Thanks in advane for any assistance o this project. I have photos of the mechanism I could post if it would help.
 
Why the need for formulas?

Normally you measure the gauge of wire, and unwind or cut off the old coils to determine if it was neat wound or jumble wound. Then just wind new wire in the same style winding until the coils are the same final size. A vibrating horn is not really rocket science. ;)
 
So, here is an AWG table: https://www.powerstream.com/Wire_Size.htm You might have to buy a digital caliper. They can be had cheap if you look. Now you have the wire gage.

You can estimate the number of turns easily enough and also the length of the wire.

A source for magnet wire is here https://www.cwsbytemark.com/index.php?main_page=index&cPath=206_226 but you have to meet a $25 min.

You can post a pic using "go advanced/manage attachments. Your posts and the ability to attach pics may be curtailed or moderated for a few days since you just joined.
 
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