Painting the keycaps for the console keyboard

The keycaps for the console of the 1130 are close to correct as they exist, but I need to make a few changes anyway so might as well adjust the colors to more perfectly match a real 1130. The keycap that will serve as the Rest KB key must be painted blue to match the other blue keys, as must a couple of caps that sit along the right side of the keyboard. The other keys are more tan than the grey color on an 1130, so I could match them as well. Some of the tan keys were originally blue, but had been colored to the tan by the factory or a prior owner.

A complication is the lettering on the top of the caps - if I recolor the tan keys to grey, I will need to either protect those legends or redo them. Most of the keys have the exact right legend already, since the keyboard I am leveraging is from a keypunch and so was the keyboard used by IBM for the 1130. The IBM 029 keypunch set the standard in its day and that was the format copied by the makers of the keyboard I bought. However, a few need changes - keys like Int Req, EOF, Erase Fld, and <-- (back arrow) are not on the keyboard I bought and will need to be added.

I might use a mask and spray some paint to form the legends, then clearcoat all the keys to protect the lettering. On the other hand, the other keys have a very slight etching that was used to create the lettering, which may cause a clash when viewing the keyboard.

I do have to fill in or blank out the lettering on a few keys that become blanks on the 1130 - that should just involve a slightly deeper coat of the enamel paint. I need to experiment with the airbrush before I commit to a particular approach.

I set up the airbrush on Sunday and began to experiment, using one of the removed blue keycaps that are not needed on the final 1130 keyboard. The keycaps are ABS plastic, according to an employee at the Tap Plastic store in Palo Alto who looked at and tested one of the spare keycaps. The process I understand is needed is to degrease/clean them with mineral spirits, lightly abrade the surface with a Scotchbrite pad (plastic scouring pad), reclean with mineral spirits, spray on an adhesion promoter made for improving paint adhesion to plastic, then spray my enamel colors.

My first test appears successful - see picture below - although this is just a grey primer I shot onto the keycap. The surface will not be as smooth as the original injection molded caps, although in part this is caused by the roughing with scotchbrite pads. I would finish up with a very fine sandpaper, 800 grit or higher, to achieve a smoother surface before painting. If this seems to hold up, I will put on a color topcoat and see what the surface looks like when that dries.

Blue keycap painted with grey primer as a test - looks good
The cover for the console printer and the box holding the display lights (the pedestal over the printer) are painted grey with a rough pebbled surface. I experimented with a stone texture spray can to see if I could get an acceptable surface and the first try looks reasonable. I will probably lessen the amount of texture I spray on, but I need very good photos of the actual 1130 in order to achieve a really good match. The other surfaces on the outside are an off white formica and a matte finish flat black on the metal base into which the keyboard, pushbuttons and rectangular indicator lights are placed.

First try to create pebble texture grey metal surface
I will wait a day for the keycap to be really dry, then test the quality of the adhesion and sensitivity to rubbing damage - even though the finished caps will be covered with a clear top coat for protection.

The paints I am using on the keycaps are Testor Modelcraft enamels, a premium line made for hobbyists to paint plastic models, which are sprayed through an airbrush. I will mix them to get the colors I want, the blue and grey tones of the 1130 keyboard. For the metal covers for printer and light pedestal, I use Rustoleum American Accents stone texture and grey primer spray cans, and will use a grey color coat and a top sealer from their lineup.

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