The Macintosh Minus - pi-powered mini Mac Plus clone with 5" CRT display
- Thread starter vorg
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The depth is longer by ratio than the real Macintosh Plus, so it isn't a direct conversion for volume. I'm sure somewhere in the CAD program I can see the real volume.
But the CRT is 5.5 inches versus the 10 inch CRT of a Mac, so I call it 55%.
Thanks, I figured you'd like it. Question would be the height of the top edge of the neck board on your CRT. Clearing that is the problem and will likely require reducing the angle of the camfer?
I've got a 10" Color CRT in a Plus, but the neck board is way too big to fit within the BackPaq. Can't change the angles there. Only solution for mine is to do a neck board extension it down and away from the A/B.
You can shallow up the angle if needs be.
edit: I like the more rakish angle of the chamfer, it's growing on me. I think it streamlines your cinderblock nicely.
However you will be needing to angle the handle recess down toward the front for finger room if you decide to take it this way. Definitely consider the TwiggyMac front bezel treatment, I wonder if you could make it deep enough and if it would be wide enough to install a USB 3.5" FDD?
I'll butt out now.
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I wish I had a color Watchman!
Glad you like 'em. Post some side on pics and requisite measurements and I can dial it in for you.
Hey guys, here's an update on my progress I posted to youtube.
I explain more in the youtube description, but I might leave this one here, use it to get the software working, and start on a V2 with better mounting, some useable ports, and other changes.
I explain more in the youtube description, but I might leave this one here, use it to get the software working, and start on a V2 with better mounting, some useable ports, and other changes.
Great video! Loving your progress up to date. Now make a REALLLLLY BIG Macintosh!
Happy Friday, tinkerers!
Not a huge update, but I did remodel my CRT after a lot of trial and error. The final (I hope) test print is going now. I'm learning Volumetric CAD is a rough way to do this, but I can't use meshes or I lose the ability to design the rest of it in CAD....
I haven't gone full Twiggy Mac yet, but the proportions of V2 are looking aesthetically a bit better. Bigger chin and deeper drafts definitely help hide some length. Without sacrificing the screen to front ratio or trying to source a super rare 7 inch CRT, I don't think it will be possible to fix it being longer than it is tall. Primarily, it should look like a Mac from the front, so frontal area takes precedent to length, in my opinion.
This one has the proper "flanges" on the front case to retain the gap but keep it light proof:
It clips my board right now, so I have to either widen the whole design and adjust the bezel around the screen (one of the trickiest parts, tbh) or shave down my PCB.
I also opened my other 5 inch TV to see if the implosion band mounts are the same as this one. They aren't so that theory is out. The actual screw holes may be in the same place, but I can't tell with just one. The curvature of the tubes should be close to the same though, so I will probably publish this as a shell so people can add components to the inside to fit their TV.
I might also play with putting the analog board on the side like in a real Mac, if it's feasible. I need to model more components into Fusion 360 to ensure my board fits. Since I plan on rewiring some pots, the power switch, and some other stuff, I could also extend the wires from the board to allow it to go sideways. We'll see. I should really at least get Mini vMac working on my pi first.
I also calibrated the CRT as best I could yesterday. Cracked as much glue off as I could; squared the deflector with the glass, and even added some magnets to bend the image in a corner that was wonky. That was scary as hell, to be honest. I just put some double sided tape down and then turned it on, placing the magnets by had when I had the best image geometry. It was scary because you can feel the deflectors as they vibrate the magnets. I have no idea how you are supposed to do this without the device on, and while I hate working next to the live high voltage like that, I assume it's theoretically as safe as my hands are steady. But I don't know how others do it. I also just put kapton tape over the magnets because I am afraid any superglue or hot glue with demagnify the neodymium.
I also ran into a small issue where, during calibration, I used a DVD player with RCA out to get an image. I played an Empire Strikes Back DVD and periodically a dozen or so lines would appear in the upper left corner. This only occurred while watching the movie, not at all during a menu. I need to test it with something else because I suspect it may be a sort of DRM that is showing up on the B&W TV that may be invisible for a color NTSC signal, but I'm not sure yet.
@Trash80toG4 let me know if you'd like this new 5 inch CRT model to flesh out the "Tiny Twiggy" design. It's still not perfect, but it's quite a bit closer.
If the next test print is still too far off, I'm going to try heating the "frame" and just pressing the glass tube into it to get the perfect radii/seal.
I think I'm torturing myself refining this because it's just so goddamn cute.
Not a huge update, but I did remodel my CRT after a lot of trial and error. The final (I hope) test print is going now. I'm learning Volumetric CAD is a rough way to do this, but I can't use meshes or I lose the ability to design the rest of it in CAD....
I haven't gone full Twiggy Mac yet, but the proportions of V2 are looking aesthetically a bit better. Bigger chin and deeper drafts definitely help hide some length. Without sacrificing the screen to front ratio or trying to source a super rare 7 inch CRT, I don't think it will be possible to fix it being longer than it is tall. Primarily, it should look like a Mac from the front, so frontal area takes precedent to length, in my opinion.
This one has the proper "flanges" on the front case to retain the gap but keep it light proof:
It clips my board right now, so I have to either widen the whole design and adjust the bezel around the screen (one of the trickiest parts, tbh) or shave down my PCB.
I also opened my other 5 inch TV to see if the implosion band mounts are the same as this one. They aren't so that theory is out. The actual screw holes may be in the same place, but I can't tell with just one. The curvature of the tubes should be close to the same though, so I will probably publish this as a shell so people can add components to the inside to fit their TV.
I might also play with putting the analog board on the side like in a real Mac, if it's feasible. I need to model more components into Fusion 360 to ensure my board fits. Since I plan on rewiring some pots, the power switch, and some other stuff, I could also extend the wires from the board to allow it to go sideways. We'll see. I should really at least get Mini vMac working on my pi first.
I also calibrated the CRT as best I could yesterday. Cracked as much glue off as I could; squared the deflector with the glass, and even added some magnets to bend the image in a corner that was wonky. That was scary as hell, to be honest. I just put some double sided tape down and then turned it on, placing the magnets by had when I had the best image geometry. It was scary because you can feel the deflectors as they vibrate the magnets. I have no idea how you are supposed to do this without the device on, and while I hate working next to the live high voltage like that, I assume it's theoretically as safe as my hands are steady. But I don't know how others do it. I also just put kapton tape over the magnets because I am afraid any superglue or hot glue with demagnify the neodymium.
I also ran into a small issue where, during calibration, I used a DVD player with RCA out to get an image. I played an Empire Strikes Back DVD and periodically a dozen or so lines would appear in the upper left corner. This only occurred while watching the movie, not at all during a menu. I need to test it with something else because I suspect it may be a sort of DRM that is showing up on the B&W TV that may be invisible for a color NTSC signal, but I'm not sure yet.
@Trash80toG4 let me know if you'd like this new 5 inch CRT model to flesh out the "Tiny Twiggy" design. It's still not perfect, but it's quite a bit closer.
If the next test print is still too far off, I'm going to try heating the "frame" and just pressing the glass tube into it to get the perfect radii/seal.
I think I'm torturing myself refining this because it's just so goddamn cute.
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I'm excited to hear you're going with the TwiggyMac Bezel! Once you have that in the can, it can be scaled up to life size. Been looking into a printed insert for my TwiggyMac hack of a cracked Plus bezel.
I can't do anything with your actual model, I've only done 2D CAD and that was thirty years ago. If you can export plan views of your model I can play with those in AI. Side and top views with the placement of your largest neck board indicated will do for BackPaq depth camouflage refinement. Front view would let me work from my extensive TwiggyMac pic collection for placement.
I've been thinking I should start a documentation thread. I've always hoped I could convince someone to do a modeling clay form of the real deal. Smooshing it into the opening against a cling wrap shield would be a near perfect reference for modeling.
I can't do anything with your actual model, I've only done 2D CAD and that was thirty years ago. If you can export plan views of your model I can play with those in AI. Side and top views with the placement of your largest neck board indicated will do for BackPaq depth camouflage refinement. Front view would let me work from my extensive TwiggyMac pic collection for placement.
I've been thinking I should start a documentation thread. I've always hoped I could convince someone to do a modeling clay form of the real deal. Smooshing it into the opening against a cling wrap shield would be a near perfect reference for modeling.
I just took a side by side screenshot of the new and old models and realized the first one has a significant design flaw. Can you spot it? First one on the right.
I was thinking of testing molds with these. I'm a total novice at casting though; I have a habit of design additive only things...
When I finish editing this new case, I can post some line-art views of the six sides of the case for you to use. To get the basic shape of the case, you can use foam or cardboard, then its really just a matter of adding some chamfers and fillets. You could also use the plastic bevel from the screen you decide to put in it to ensure a perfect fit.
From there, it's sanding and filling till it looks right and feels as smooth as you want it to. A mold can then be made from that to make it out of something tougher.
I was thinking of testing molds with these. I'm a total novice at casting though; I have a habit of design additive only things...
When I finish editing this new case, I can post some line-art views of the six sides of the case for you to use. To get the basic shape of the case, you can use foam or cardboard, then its really just a matter of adding some chamfers and fillets. You could also use the plastic bevel from the screen you decide to put in it to ensure a perfect fit.
From there, it's sanding and filling till it looks right and feels as smooth as you want it to. A mold can then be made from that to make it out of something tougher.