GE M935AWL restoration

[Yamamaya42]

You could always look up the EIA code on the tube, there should be one to find exactly who made it.

[old_tv_nut]

I believe the safety glass must be removed when rebuilding, as the bonding material would not survive the oven temperature.

IIRC, the rebuilt tube I bought from Scotty had no safety glass, but that was OK as I was using it in the CTC-5 until I could get a 21AX. Then when I got the 21AX, Doug helped remove the glass from a dud glass tube with a cataract and put it on the rebuilt tube.

I don't recall any strong smell on the Zenith tube that Doug did for me.

[kvflyer]

At the risk of derailing this thread, sorry, maybe I should practice on the original RCA 25XP22 that's in the set. The replacement is a 25AP22.

Your thoughts, guys?

[Yamamaya42]

Speaking of Scotty. as far as I know, Shango is using his method here.
https://www.youtube.com/watch?v=h6hGd_ZPaqY

[Yamamaya42]

Originally Posted by kvflyer

At the risk of derailing this thread, sorry, maybe I should practice on the original RCA 25XP22 that's in the set. The replacement is a 25AP22.

Your thoughts, guys?

The rectangle tubes will always be a higher risk than the round ones, that being said, how you do it still depends on the type, If it's RCA, you need heat or soak it in water for a very VERY long time, or if it's the green gummy Zenith, a heated wire is used to cut through it.

[damen]

I had a friend who worked at Video Display Corporation in Georgia. He once told me the tubes were heated up and the safety glass removed on all tubes before rebuilding. Most of the tubes they sold had a tension band installed, but for an additional fee they would laminate a glass back on to the tube instead. I got several of these tubes from them because I wanted the original tinted "frosted" look.

[bandersen]

Question for the group. Can you safely leave the yoke and convergence stuff on the neck while removing a cataract?
I removed it from this one as I was concerned about damage but now I'm wondering if I could have left it alone?

[Yamamaya42]

Originally Posted by bandersen

Question for the group. Can you safely leave the yoke and convergence stuff on the neck while removing a cataract?
I removed it from this one as I was concerned about damage but now I'm wondering if I could have left it alone?

Yes you can, however is self defeating as you will need to do the convergence and purity setup anyway when you are done after no mater what, and on the round tubes, the static magnets are a bit more fragile then the later ones used on the rectangle ones, so most just take it off, but i have left them on for rectangle ones, removed them on round.

[bandersen]

OK. I would think if one was careful not to disturb anything on the neck, the convergence and purity would still be pretty good.

[Yamamaya42]

That's correct, relatively speaking, but any changes will have subtle effects on the final setup, for example, N,W,S E, final positioning of the set will have sight effects on purity and convergence, get it perfect in one position, turn it 90 degrees, or 120, it's no no longer quite as exact, this may not matter to the average viewer, but to those who spend hours with a magnifying glass getting convergence as spot on as they can, it does.
And as Old Tv Nut pointed out a while back, do anything that causes a noticeable change to vertical height / linearity, like a new oscillator / output, or resistors / caps in the vertical area, going through the setup procedure is unavoidable once the set is at it's final location to get best picture, no matter if you had the parts off or not, but, it will make it a bit easier to keep them on, yes.

[Electronic M]

In my experience if adjustment looks fine from 10' away and you don't like to press your eyeballs to the glass leaving the neck hardware one will allow you to skip redoing the setup an be unnoticeable from before the work.

[Yamamaya42]

Originally Posted by Electronic M

In my experience if adjustment looks fine from 10' away and you don't like to press your eyeballs to the glass leaving the neck hardware one will allow you to skip redoing the setup an be unnoticeable from before the work.

As i mentioned before
I'm severely nearsighted, and my glasses cause very bad chromatic aberration, so i do setup w/o them with my face 3 inches from the screen!
And it has ALWAYS bugged me if it was not as perfect as I could get it, so I often spend 2 hours or longer going round and round till it's as close as I can get it, I have done this since High School days!

[bandersen]

Two pieces of this 3M tape are the same thickness of the original bonding agent. I placed them near the edge in six places then applied a bead of silicone.
I'll left that sit overnight and reassemble tomorrow.

[kvflyer]

Silicone instead of packing tape on the edge?

[Yamamaya42]

Congratz on your first one!

At least you did not have to deal with a secondary CAT-A-Ract, like I did the first time!

https://imgur.com/Cub0Mxk

Yeah i posted this before!
He's a brat!