It seems like a sweet project is coming together right around the time when I'm ready for more work. Banking info and numbers have been traded so that seems positive. If money lands then I'll be able to talk (and release WIP videos) about it.

Can you guess my new project by this part? (dimensions are close but not yet exactly correct)

Hint #3: The base part shown is an inner frame and is around 43cm (17") wide.

Hint #4: At the end of the project there will be six of them and they'll be in a museum exhibit.

Hint #8: These are metal frames to which rather beige case parts will be attached. The blue is where the glass would be.


Ok, I now have permission to talk about this project in full and in public. I'm working with Alan Kay to build six replicas* of a Xerox PARC Alto display for use in a museum exhibit**. Visitors will see a real Alto and then walk over to one of the replicas to futz with Smalltalk '78***.
Here's a nice writeup of a different project that rejuvenated an actual Alto.

* by "replicas" I mean that they'll look and feel as close to the original as possible but inside will be modern technology. I'm not replicating the original CRTs and driver electronics.
** the museum is in the UK (where Kay now lives) but I'll leave it to them to make their own announcement.
*** this version of Smalltalk was thought lost but then was saved by a dumpster diver who found Alto drive cartridges in the trash!

My general plan is to laser cut and bend inner frames for the portrait oriented displays and the uniquely U-shaped bases, then hang the case elements (with their many complex curves) and electronics on those frames. I've ordered a large format additive printer to avoid seams and joints where they don't belong and while that's in transit I'll be running materials tests and furthering the CAD drawings. I have reference photos of Kay's personal Alto so that I can nail the dimensions.

If this seems to you a bit out of the blue then you're a bit correct, but I have a history of reproducing real and theoretical intellectual infrastructure (e.g. my two Memex builds) and I used to work as a prototype engineer in the PARC lab where the Altos (and laser printing, and Ethernet) originated. That all happened well before I worked there, but that's how I'm connected to that community.

Now that I have permission to share this work I'll start posting WIP photos, videos, and snippets of the design, build, and installation of the replicas. I'm hecking excited to share!

In the meantime, if you're into the Alto then definitely swing by this link to see a metric boatload of photos and document scans like this one from the hardware manual.

While looking into texturing techniques to replicate the original cast parts of the Alto displays I ran across this video about wall texturing and painting techniques. Now I may never be satisfied with flat, boring walls.

I have a few rollers ordered but if those don't work out then I might need to print TPU rollers or CNC cut foam blocks for a custom texture. The last time I tried to replicate a surface texture was before I had additive printers or CNC cutters so this is a new kind of fun for me.

It's fun looking for less than a dozen steel hemispheres because their listed uses are so random. It's a handrail topper. No, it's a chocolate mold. No, it's a salad bowl. No, it's a fire pit!

So far I'm pretty happy with OSH Cut. Their instant quote system is pretty good at telling me how to tweak my designs to get the best cut and bend. The one hiccup I had was quickly and effectively responded to by a support person, Emily. I ordered a couple of samples to see the quality of their cuts and finishes and they look good, so my next step is to polish the design a bit and then order parts for a prototype!

The display swivel mechanism design is coming together. It's basically a cylinder and a hemisphere that squeeze a hemisphere that's welded to the display's base.

Here's one a reference photo of Kay's Alto that shows the display resting on the base's hemisphere. He told me that in retrospect they didn't need a free swivel like that because they only ever tilted the display up and down like nodding your head. It could have been a single-axis.

There's also a sliding potentiometer peeking out from the bottom of the display. I can only assume that it allows the user to change the intensity of their 70s vibe.

A Creality CR-10 S5 is coming my way so I need to rearrange my shop to make room. It has a print volume of 500mm x 500mm x 500mm so it'll handle Alto case parts without adding unnecessary seams. 😸

I plan on reselling it after the Alto replicas ship and I've printed helmets and busts for a few friends. I try not to keep any of my work (except my custom tools) and I generally make smol mechatronics so this big printer isn't a good use of space in my decifactory.

I sort of like the inebriated look of this sweep before I add parametric constraints. In the future it might be fun to make a desktop display with this sort of semi-organic and irregular shape.

There are roughly eleven bazillion shades of old computer beige. I want these replicas to look like they are old new stock that we recently found buried in PARC storage.

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@trevorflowers this sounds amazing, very interested to witness the process! Congrats on being a part of it!

@tendigits Thanks! Yeah, this project arrived just at the right time in my life and includes many aspects that are my jam. I feel very lucky.


It can be frustrating to know what you want, but have no idea what to call it, and therefore what to search for!

@trevorflowers There's a fun bit in Zodiac where the main character is wandering around a hardware store looking for things to use completely differently from their intended purpose—as is traditionally done in hardware stores.

I had a moment a couple months ago, looking at a Nylabone in the pet section, thinking "if I had a lathe, this would actually be perfect for repairing my trailer hitch".

@varx I vaguely remember that scene but I read it years (decades?) ago. But yeah, having machines and skills to turn, mill, and weld turns almost any product into a raw material.

@trevorflowers Even without that! There's a YouTube channel I follow (NightHawkInLight) that's mostly about DIY stuff (primitive skills, air cannons, sparklers, random stuff), and it's amazing how many things he casually appropriates from their intended uses -- a steel brake line for a thermic lance, a furniture floor-protector for a flapper valve, stuff like that. And that's without tools.

(My trailer repair ended up using a chunk of I think a thick rubber gas line or whatever.)

@trevorflowers I'm really excited to see how this comes together! Are you going to use CRTs at all or will these be LCDs behind glass/plastic?

@phooky They'll be LCDs. It won't be as cool as CRTs but we don't have time/budget/skillz to make CRTs work and look right.

@trevorflowers @phooky If the hardware you're running the Alto emulator on has a GPU you probably could at least simulate the characteristics of the LCD display. The retro/emulator community has invested a lot in this sort of technology to better repro CRT-based gaming on modern LCD displaye...

@swetland @phooky That's a good point. We haven't settled on the computer. Originally when I thought I was making miniatures we were planning on a SBC but at original size we have more room inside (where the CRT was) and as an indefinite museum exhibit it needs to be both stable and easily replaced.

@swetland @phooky Something like a small industrial PCL but those are usually lacking in GPUs. Maybe an Intel NUC that they're aiming at gamers? Suggestions welcome.

@trevorflowers @phooky You probably don't need a super-high-end NUC -- the Alto appears to have had a 606x808 pixel display. You'll want a modern higher res panel for room to render the artifacts, maybe 2560x1440. But having the GPU's work be "scale up and distort" is not going to make it break a sweat.

@swetland @phooky Given how little we're asking of it (dinky emulation, relatively few pixels, etc) I suspect that last gen NUCs with integrated GPUs wouldn't even need to turn on their fans.

@trevorflowers @phooky I'd suggest X86-64 Linux -- Intel NUCs tend to be decent for this sort of thing and the modern Intel GPU while not amazing, probably has enough performance to emulate the various artifacts of the original CRT display.


Would some simple optics be beneficial in helping create those artifacts? (Or rather, beneficial enough for that to make sense.)

Things that come to mind that might be:
- pixel shape distortion (but that might be easy with a very slight superresolution),
- pixel shape and cross-pixel blending (but that would require one (Fresnel?) lens per pixel, which would probably be very hard to produce~~).

Also, are there ways to replicate the CRT's refresh cycle (both the existence of the flicker and the fact that each pixel is dark for a large fraction of the time)? I guess you could blink the backlight?

@swetland @phooky


A notary I knew in the middle '80 had a bulky central computer with terminals in portrait mode, to fit a whole sheet of legal paper, but it wasn't an Alto.

@GustavinoBevilacqua @trevorflowers

In a carton somewhere I have a vertical-format monochrome monitor, sold as a Mac peripheral, for desktop publishing applications and such.


May I ask, what the difference of ST78 wrt ST80 are? Thanks!

Otherwise, fantastic project! Where can I stay up to date?

@alexshendi1 I'm not enough of a Smalltalk nerd to answer your first question. It's the version that Kay likes the most and I trust him to know. :-) As to where you can stay up to date on the project, that would be this thread.

@Dreamer9177 The Alto shipped in 1973 and the THGTTG show was in 1981 so maybe the Marvin designers were inspired by the display!

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