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.

IMG_3070
Kitties! Again, not what this post is about.

IMG_3072
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.

IMG_3074
That foam is everywhere and is all nasty. But it’s a cheap keyboard and I’m not going to remove all the foam.
IMG_3075IMG_3082
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.
IMG_3084
Broken hinge end. I tried gluing it but it would immediately snap. It’s under a fair bit of force from the spring.
IMG_3273
Just not enough meat to use adhesives.
IMG_3275
Cleaned up.
IMG_3279
Some suitable steel was cut.
IMG_3280IMG_3281
Forming the channel with an arbor press, vise and a 1/4” square toolbit.
IMG_3282
The channel.
IMG_3285
Drilled a hole for the post.
IMG_3287
The spring fits but I had to squeeze it slightly oval to get it to bottom out.
IMG_3288
Some washers shim up the channel because of a step down after the post.
IMG_3290IMG_3293
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.
IMG_3295
That foam…nasty.
IMG_3299
It fits! It came out surprisingly well for a speedy hack repair.

No comments: