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Transplanting 9-inch CRTs - A Journey

Hey, it's been a few years, but thought I'd chime in.

Unless you happen to have a CRT out of a FANUC CNC machine, the spacers I made won't work. And even then, I do not know what model of monitor unit it was (there are several styles I've seen in a search). Picture below is not mine, and based on my memory from 5 years and a pandemic ago. (As far as the originals, long story I'm tired of repeating is that due to a myriad of things happened that led to the original photos being lost). Shouldn't need to be said, but I accept no liability. Use at your own risk.

View attachment 93462

I think one would be better served to take measurements and experiment as I did for their individual screen and mounting assembly.
My goal is to transplant an Apple IIc monitor's CRT into a Macintosh Classic, just like Adrian Black did in his video, with these particular spacers. So why wouldn't it work?
 
My goal is to transplant an Apple IIc monitor's CRT into a Macintosh Classic, just like Adrian Black did in his video, with these particular spacers. So why wouldn't it work?
Unless you happen to have a CRT out of a FANUC CNC machine, the spacers I made won't work.

The metal band around the CRT that attaches it into whatever chassis it was designed for is likely not the same. As mentioned, the link has all the STLs. You can try if you want, but you do it at your own risk. I'm not liable if the prints come back and don't fit.


I have no idea what spacers he's using, I haven't watched any vintage mac/computer stuff in years now.
 
Great progress, jessenator, I appreciate your attention to detail!

Hopefully not going off topic here, but today I found what appears to be an never used 9" monochrome security monitor with a Samsung 240AG4A CRT - I presume I'll be going through a similar process here should I decide to replace one of my burnt in Plus/SE/Classic CRTs?

It's the same CRT as this:

https://www.ebay.com/itm/Samsung-CRT-Monitor-Picture-Tube-Type-240AG4A-/184185290924
I'm kinda surprised that people are doing these exotic swaps unless it's to change phosphor color (I'd love an amber Mac Plus). The original tubes are not rare, donor machines are inexpensive... I have a half dozen spare tubes sitting here.
 
This ;)

When I was looking at the close-ups of the amber CRT (Nickpunt's photos) that's on the way, the band appears to have a screw to keep it in place, but there's a secondary band to clamp the RF shield(?) for the IBM 5155 part assembly (analog board etc all hooked up). The actual band around the tube looks to be crimped on there :/ I don't want to attempt it, really, unless someone can conclusively state that there's no implosion danger.
The factory implosion band is spot-welded together and is under tension. You do not want to remove it because it is an integral part of the tube design. The purpose of the band is not to prevent implosion, but rather to direct it. The front of the CRT is convex; ergo, for the screen itself to implode, the edges would have to move outwards. The implosion band prevents this, so that the glass failure will occur elsewhere in the tube, if it occurs at all. The net result is that if the tube suffers fatal trauma, the screen (user-facing) side will remain intact and any flying glass fragments will be inside the enclosure of the appliance.

My dad used to shoot at old surplus radar tubes with an air-rifle (long before I was born). He told me a couple of times he hit one in the center of the screen, and had the electron gun shatter on the wall behind him because the implosion propelled it forwards. Fun times. No idea how he survived long enough to have a kid. He also derailed a tram (streetcar) with a jar of touchpowder, and started a fire with a volcano mixture he was making. I have a piece of shrapnel in my left hand left over from one of his experimental projects (long, fun story).
 
Okay, so I'll need to design my own spacers. No big deal.
Hey, sorry for the uncouth response I gave. I think I've just felt burned in the past with interactions around my 3D printed stuff, and that was unfair to project that resentment onto you. I hope I didn't come across as trying to gatekeep, just an imperfect human being imperfect human.

I hope those work for you. I gave in and watched the video (no idea it was that long ago), and I'm pleasantly surprised it worked for the //c as well. Heh, mostly. Maybe the analog boards are just too different between the SE(/30) and the Classic for a good fitment. Thank goodness he didn't electrocute himself. I never dared touch the yoke when it was on...

It's funny enough, but I happen to have a similar CNC machine CRT I bought a while ago. Your spacers might work with it.


View attachment 93480
Looking at the specimen you've got, you may not even need them—the tabs are screen-forward like the compact Mac one. Do a dry fit and see!

oh, the funny coloured phosphors are absolutely a large part of the allure. MacOS in amber is weird but rather pretty.
Cheesey has the best screen: amber. Was quite happy to pass it on :) well, the screen was all good, but that case. I still cringe a little thinking about how terrible that retrobrite job went :ROFLMAO:
 
Cheesey has the best screen: amber. Was quite happy to pass it on :) well, the screen was all good, but that case. I still cringe a little thinking about how terrible that retrobrite job went :ROFLMAO:

Your amber-mac is sitting in pride of place with the interesting compacts on the shelf :-D. I still love it.
 
Hey, sorry for the uncouth response I gave. I think I've just felt burned in the past with interactions around my 3D printed stuff, and that was unfair to project that resentment onto you. I hope I didn't come across as trying to gatekeep, just an imperfect human being imperfect human.

I hope those work for you. I gave in and watched the video (no idea it was that long ago), and I'm pleasantly surprised it worked for the //c as well. Heh, mostly. Maybe the analog boards are just too different between the SE(/30) and the Classic for a good fitment. Thank goodness he didn't electrocute himself. I never dared touch the yoke when it was on...
There's absolutely no problem; you're right to warn me that it might not work. Besides, it's not much fun when it works straight away.
The most dangerous part of the yoke is the copper coil. I've accidentally touched it before, but I wasn't shocked. Still, it's important to wear gloves and avoid touching a CRT that's in operation as much as possible!
 
Still, it's important to wear gloves and avoid touching a CRT that's in operation as much as possible!
I 3d printed some channel lock pliers I found on thingiverse. They were garbage really, but got the job done and I didn't have to touch any metal 😂 That being said, ISTR some vintage photos of Mac assembly lines of the calibration, and it was just folks reaching right in there :|
 
I 3d printed some channel lock pliers I found on thingiverse. They were garbage really, but got the job done and I didn't have to touch any metal 😂 That being said, ISTR some vintage photos of Mac assembly lines of the calibration, and it was just folks reaching right in there :|
I was so proud of myself yesterday. I wanted the plastic adjustment toolset and I was about to buy one off Amazon, then I went out in my garage to check my Drawer O Tools and I found... the EXACT set I'd just been about to buy again. https://www.amazon.com/Philmore-Anti-Static-Alignment-Trimmer-63-910/dp/B01MXZGEXT
 
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