NEC APC H412 (Blue Ovals)

[Ail]

Hey everyone,

I just bought a H412 off of E-bay and cleaned it up nicely. It's in great shape minus one very important thing, the switches are horrifically dirty. To the point where keys bind often, don't always register, and even get stuck to where it will register the same key over and over until I press the same one again and get it to unstick.

I see that these cannot be opened, what are my options for cleaning them? This thing is pretty useless to type on and while it is still a nice collectors item given the condition, I would like it to be usable. Thanks for any suggestions.

[ohaimark]

You can nuke them with PTFE dry lubricant spray, which might kill their click. -shrugs- There really aren't many other things you can do.

[Ail]

Yeah that was kinda my thought, I was going to test lube on one switch and see what happened. I'd hate to lose the click, but if it's unusable with the click, what's the point anyway?

[XMIT]

Remember to *rotate* the key caps off, left to right, while pulling up with a key cap puller. If you just pull straight up you'll destroy a switch.

You might have some luck desoldering all the switches and cleaning them with isopropyl alcohol. The dirt will still be in the switches but hopefully clear of the sliding parts and the switch plate yielding better key feel. This sort of helps. That's the best you can do.

The switch casings are Delrin so glue won't work to hold them together. Epoxy might, but, Delrin is really slippery.

Good luck!

[ohaimark]

Rotate might be confusing if you don't specify the axis. Tilt might be a better term?

[XMIT]

Probably. I had a really nice write up of how to do this somewhere and I can't find it now...

...oh right, Ander put it on the Wiki after I gave him one. wiki/NEC_APC-H412

Aha. Found my old writeup:

post235667.html#p235667 (text)
keyboards-f2/nec-blue-ovals-t10861-30.html#p238305 (video)

Lots more in that thread, I really tore into one of these boards a while ago.

See also:
wiki-talk-f33/new-nec-apc-h412-page-t12076.html

[XMIT]

Oh yeah, and - be REALLY careful with that Space bar. It's thin ABS. I bent mine while cleaning it in too hot water and managed to snap it clear in half bending it back. But a little drop of acetone and a steady hand got it back together. elecplus has that board now.

[Ail]

Well the good news is I already made it through the keycap removal and cleaning phase without breaking or warping anything. I must have been lucky because although I did not pull directly up, as I generally rock all caps I pull back and forth (space invaders withstanding), I certainly did not rotate them. Either way, I don't know I have the patience to desolder all of them since I have about 10 other boards waiting to be desoldered. Maybe after I pick up a HAKKO 808.

Anyway thanks for the help, guys.