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.

2 comments:

Unknown said...

Mine is broken exactly like yours. Thanks millions you almost saved me. But, my keys ct 370 seem to be sealed. How do i get the bad black one out?

Felice Luftschein said...

Not sure? It may not be sealed but you just have to wiggle it up and down to get it free. Also removing the foam helps. Sometimes seeing if you can remove the white keys around it too. It's a puzzle.
Nick