AltairClone.com

I found some STL files online for a nice card cage for an Altair 8800c system. Since I do not have a 3D printer or any friends with one I am looking for an online service I can send the design files to hand have them print for me. Can anyone recommend a good place, and any suggestions for what material I should request?

Thanks!

I found a local printer at a very reasonable price through www.viewstl.com. If somebody else needs printing service, they seem pretty good at finding service.

Can you post a link to the card cage STL file please?

Original style card guide design is available here:

http://www.the-planet.org/Retro/Altair_card_rail.stl



And the full card cage STL is here:

https://pinshape.com/items/110209-3d-pr ... ard-guides

Thanks!

I would advise people against the rack style STL file. I had the 9 card printed for me and it doesnt actually work. Good concept but the dimensions don't appear to allow the cards to fit. The original style guides are excellent.

I should clarify, the card cage STL can be made to work, as long as you are doing the minimum board population, i.e. not utilizing any of the active termination, reset or LEDS. P1 power is blocked, you will need to use P2. Fuses/Jumpers F4, F5, F6 will have minor interference to jumpers, but actual fuses are not workable. There will be some minor interference with the board mounting hardware depending on what holes you choose to put the standoff in. But most interference issues can be resolved with a dremel tool.

First things first, I want to give a "shout out" to Walt Perko for drawing the 3D models for the 9-slot card cage (and other cool things) and to you, Curt, for linking the STL files here. It's definitely a great start.

But I think the biggest problem with the STL files is that the mounts are all 1/4" too short. I think we should re-draw them and extend the mounts by exactly that amount. I measured with a micrometer, and it's tits-on 0.250" too short. I may redraw them when I get time.

And you're right - this still leaves some slight interference problems if the termination circuitry is installed. The capacitors can be leaned over though. On the other side, the LEDs are in the way, so the mounts need to be clearanced there. We could modify the STL file to provide a detent for the LEDs but I think I'm OK leaving the 3D model alone and expecting the end-user to grind a little bit if they want to populate the board with power LEDs.

This is what I see:

Agreed, kudos to Walt for this design.

Actually the design is good, the fingers don't mount to the connector holes but the the "IMSAI" mounting holes on the 9 slot motherboard. I made the same mistake when I first tried to assemble. If you mount directly to the board they work great with a passive back plane. Really my ONLY criticism would be the card guide slots are a little wide and allows the boards to wobble a little more than "stock" slides.

All in all I am very happy with Walt's design. Thanks Walt!

You're so right. I see what you mean. The card cage works pretty well that way, but as you said, it mounts directly to the board so the terminator components can't be populated as-is. And I notice the card sticks up above the top of the card cage, so ejectors won't work.