osiweb.org

Recently, I had the need recently to become crudely acquainted with some MCAD software. I've also been moving into a new house, and have been moving all my retrocomputing stuff into my new lab, so I've had a good look at some of my machines for the first time in a while. I noticed that my Superboard II and the 542B keyboard on the C4P are missing brackets for the spacebar. I had previously thought of making a crude replacement on the Makerspace laser cutter, but this was an opportunity to try my hand at a proper replacement. I made a model of one of my remaining brackets, and flipped it to make a pair, and sent it off to shapeways to get 3D-printed. I just got the result back today--not bad, if I may say so. The stem is a tad thicker than the original, but it fits tightly into the spacebar slot with the help of some pliers. Now, I finally have properly working spacebars! They cost about $2.50 each from shapeways, depending on the material, and I will make them available for anyone who wants them to order. I'll also post the CAD files on the web site, if anyone wants to improve them. Here are the pics:
Dave

Here are the shapeways links. I ordered mine in the black color, at $2.45/ea.

http://shpws.me/oWVp

http://shpws.me/oWVo

Dave

Nice! I'm really intrigued with 3D printing. I'm waiting until the prices come down and the build volumes go up, ultimately to be able to print a case big enough to hold a Superboard-sized motherboard.

Speaking of keyboards, has anyone thought of replacing the standard OSI keyboard with something else? Back in the day I came across a spare keyboard from a terminal and I started modifying it to be a replacement OSI keyboard. I drilled holes in the PCB in order to break the connections of the existing matrix, and started soldering wires on to re-assign the keys to match the OSI keyboard. I was also trying to wire up the numeric pad. Never quite finished, but I still have it.

I guess another option would be to use an existing keyboard (say from a Commodore 64) and modify the monitor rom to support the different layout. Of course this would cause problems for games that scan the keyboard themselves and expect specific keys in their normal positions. I successfully did this for the Commodore PET... see here:

http://www.6502.org/users/sjgray/projec ... index.html

Steve

That would be nifty. If a keyboard were set up as an 8x8 matrix, then only a ROM change would be required. If rewiring were needed, then it may be simpler just to reproduce the OSI matrix, for up to 64 keys.

BTW, impressive PET site!

Dave

Dave, I'm surprised how cheap that is. I thought it would be cost prohibitive. 3D printing rocks!

Phil

Yeah, I was pleasantly surprised. I started out wanting to make replacement up/down paddles for my Tek 370 curve tracer, and, like the brackets, figured I could use the model to make an outline for a laser cutter, but I was curious to see how much Shapeways would charge. Once I saw the price (also about $2-3), I made up the spacebar brackets right away. I guess they are pretty small after all, and don't require too much material or time. Since the don't have gray as a color option (The natural color for an instrumentation control), I actually ordered the 370 paddles in the "Royal Blue" to see if it's close to the IMSAI switch paddle color. If so, I'll make up an IMSAI paddle switch model for Shapeways as well.

Dave