repair on Casio CTK-496 keyboard

[Cliff k]

I have a friend (who happens to be a nun) that has a problem with a Casio CTK-496 keyboard. One of the keys 'dangles' loosely. If you tap it it will bounce up and down and never come to 'full up'. I removed the cover and the keys around the affected key. The problem is that one of the little rubber contacts (I think that is what they are called) is torn and will not stay in the upright position. That explains why the key won't stay 'full up'. I'm posting a picture of the area in question and would like to know if there is anything special about replacing the part. Do you simply pull out the old one and put in the new? I read somewhere that you have to coat this thing with something. I don't want to install it improperly and there's no info on Casio's website. I'd appreciate any info you could give me. Thank you so much, in advance.....cliff k

 

[Tha fios agaibh]

On the underside where the rubber contacts the board there should be conductive carbon paste. (black or grey gook)
Try searching for keyboard repair paste.

God speed.

 

[dave9]

^ Based on what was written, I am not getting the indication that there is any repair needed to the carbon traces, just a replacement key dome, which since they seem to be integrated into a strip of several, would mean replacing the whole strip.

I take it you have found a replacement rubber dome strip?

One thing you might want to do is take a dry paper towel and wipe any oily residue off the carbon traces. Typically these domes are made of silicone rubber and over time they sweat oil out and if enough builds up it can interfere with good conduction.

It would also be good to blow as much dust out of it as possible. Otherwise if I understand what I'm seeing, it just looks like the underside of the keys have white grease on them?

 

[Cliff k]

^ Based on what was written, I am not getting the indication that there is any repair needed to the carbon traces, just a replacement key dome, which since they seem to be integrated into a strip of several, would mean replacing the whole strip.

I take it you have found a replacement rubber dome strip?

One thing you might want to do is take a dry paper towel and wipe any oily residue off the carbon traces. Typically these domes are made of silicone rubber and over time they sweat oil out and if enough builds up it can interfere with good conduction.

It would also be good to blow as much dust out of it as possible. Otherwise if I understand what I'm seeing, it just looks like the underside of the keys have white grease on them?

Thanks Dave for the reply and also to the reply above, Tha Fios agaibh. As you can tell, I've been away from the computer for a couple days. All of the notes will play. The only problem was the affected key dangled loosely all the time. The problem was the little dome under this key was torn at its base almost half way around. Simply putting it back up 'fixed' the problem, but the first time the key is depressed -bingo: key dangle! Anyway I found a place to order a new strip and am waiting for it to come. I've wiped down all the grease from the keys and gotten out as much dust as possible. I'll let you know how the repair works out when the new strip gets here. Btw I don't think I will need to add any paste because all the notes do work. Thanks for your interest and advice....stay tuned
cliff k

 

[Cliff k]

Thanks Dave for the reply and also to the reply above, Tha Fios agaibh. As you can tell, I've been away from the computer for a couple days. All of the notes will play. The only problem was the affected key dangled loosely all the time. The problem was the little dome under this key was torn at its base almost half way around. Simply putting it back up 'fixed' the problem, but the first time the key is depressed -bingo: key dangle! Anyway I found a place to order a new strip and am waiting for it to come. I've wiped down all the grease from the keys and gotten out as much dust as possible. I'll let you know how the repair works out when the new strip gets here. Btw I don't think I will need to add any paste because all the notes do work. Thanks for your interest and advice....stay tuned
cliff k

Just a follow-up to finish this thread. The dome strip came yesterday and I installed it right away. After re-assembly the keyboard is now fixed and working properly. Thanks guys for your help!
cliff k