I recently found a 10 button 1500 that looked great except for the dial. The buttons were sticky and badly faded. Somebody must have spilled soda on the dial. So I took pictures on how I cleaned it.
This is certainly not the only way to clean a dial, and certainly not the best way. This is just how I did it. But it may be some help to somebody.
Firstly, remove outside dust covers and note the rear switch stack under another dust cover.
Remove the screws holding the circuit board down. You can't remove the board off, as it is connected with soldered wires to the button assembly, but removing the screws will give you room to loosen nuts later on.
Now, remove the back four screws/nuts on the corners.
Next, unscrew the nut sandwiched between the circuit board and the metal plate on the corner. This nut is bonded the the screw shaft. Use a small wrench for this part. This removes the switch/board assembly from the buttons.
With the two parts apart, disassemble everything. Take care with the delicate switch assembly, and the springs as they can go flying!
Now, the tedious part, clean all the parts with soap, water, or whatever you use. Be careful with using solvent, as it will remove any date and code stamps. You can also use steel wool on the buttons to remove some discoloration.
Reassembly time! First the buttons. (make sure they are in order!). Then the 4 horizontal bars. Next the plastic screen. Then the 3 vertical bars and springs. I also lubricate pivot points and moving parts with soft pencil lead.
Then cover the back with the white plastic piece with square holes. Make sure all the bars are in the proper slots and the white piece is correctly seated.
Then slot in the grey "pull bar" into the metal switch assembly. Confirm the rear switch assembly is correctly installed. You can also use a pencil to lubricate the pivot points here.
Carefully rejoin the button stack and the circuitry. Starting with the sandwiched nuts, then the corner screws. Then attach the circuit board with the corner nuts and middle screws. Replace dust covers, and Finished!
Hope this helped somebody in their dial adventures.
Things I have learned: don't drop the screws, and DON'T REFURBISH UNLESS YOU REALLY HAVE TO!
-Kenton
This was very interesting reading. Coincidentally I just did a touch tone refurbishment last week for my Christmas project.
The model was a bit differrent, mostly because the circuitry was not attached to the buttun unit.
I first read an article in Dutch about it. The method described was very similar to yours.
So what I did was also very similar to yours. The pencil lead trick was new to me. I´ll do that next time.
I have one tip to add: when opening the button unit, take care. Otherwise the springs go all over the room.
I´ll post pics later of my Christmas project, but my dial refurbishment is not so elaborately photographed as yours.
Yes, being careful with the springs is very important. The first dial I did, a spring went flying, and I wasted half an hour on the carpet. 8) Super fun.
I saw the graphite trick in a BSP somewhere. I think it was originally meant for plungers and other switches, but I think it should work fine in the TT dial. Graphite doesn't attract dust and gum up.
Thank you-
Ken
Only half an hour? Well, if I will ever make a hobby room again I will:
- not choose a METALLIC floor covering (mine is vinyl tread plate design, aluminum colored. Looks cool, not practical if you work with small metal parts)
- put a light UNDER the workbench.
I will use the pencil method when I do my next touch tone dial. This time I used a small drop of clock oil on the sliding plastic parts and wiped it off with a paper tissue.
Thank you Kenton for sharing your tricks on ' how to refurbish touch tone ' Now its simple... more simple :)
On the subject of lubrication. I'm no 100% sure what to use. It probably isn't crucial, as long as the oil is very light or the graphite is soft.
Does anybody knows what they used originally in the factory?
Thank you
-Ken