Sunday, March 06, 2016

Casiotone CT-370 Major Minor Key Repair

My Casiotone CT-370 had a problem with a loose power jack connection.IMG_3058IMG_3061
I desoldered the old one and soldered in a new one. It was pretty routine. This blog post isn’t about that.

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Kitties! Again, not what this post is about.

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I discovered that the F sharp (or is it G flat?) key has a problem. It’s loose and broken. Not really qualities I look for in a piano key. Or any key.

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That foam is everywhere and is all nasty. But it’s a cheap keyboard and I’m not going to remove all the foam.
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I found I had to pry this white strip away to remove the key, and the two white keys on either side needed to be removed as well.
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Broken hinge end. I tried gluing it but it would immediately snap. It’s under a fair bit of force from the spring.
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Just not enough meat to use adhesives.
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Cleaned up.
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Some suitable steel was cut.
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Forming the channel with an arbor press, vise and a 1/4” square toolbit.
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The channel.
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Drilled a hole for the post.
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The spring fits but I had to squeeze it slightly oval to get it to bottom out.
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Some washers shim up the channel because of a step down after the post.
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Two brass #2 screws fasten the channel to the key. I sawed a slot and widened it with files until it approximated the form of the broken bit. Some repairs are best done by eye.
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That foam…nasty.
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It fits! It came out surprisingly well for a speedy hack repair.