Why not? It's no less stable than a glass tube, as long as there's no air in it...

I always thought the metal CRT's were more fragile. Is the biggest difference finding replacements? Metal 21AXP22A's are harder to find than 21FJP's?

Not more fragile, just more susceptible to losing vacuum if you ding the rim where it's welded together. It's more of a concern when the tube is out of the set, in it's rightful place, it's just as good as an all glass one. Yes, they are very hard to find. Ask Mark how long he waited for one for the Wingate, and how much he gave when one came his way...

I got lucky, an ARF member sent me one for the cost of shipping. Said he didn't know if it was any good, and mailed it Greyhound uncovered in a ratty cardboard box. Made it just fine, and it's still happy in my CTC-4. Thanks, Tom!

Great..I'm running it! :D
Here are more photos.

LOL! I waited 4 years... and paid, well, like a lot for it! :):D

Those remaining caps may make a difference for the convergence and settle it right in. Is the delay line OK? It looks like the color info is shifted slightly.
This is truely a great find. We dont have sleepers like this in S Florida. Every one got rid of their "junk" before moving here.

Wonderful TV!