What kind of adhesive/glue can I use for this?

I'm just trying to figure out what kind of stuff you're supposed to use on a picture tube safety glass like this one? You might say I sort of "found" a replacement piece of safety glass for the TV I've been working on which was recently restored.

And where would I be able to purchase the glue or adhesive which is supposed to go between the safety glass and the front of the picture tube?

My memory is not good. I think we used a vacuum chamber to suck out the air bubbles in the adhesive.

Is your antique TV 20 years old or more?
TVs for the last 10 years have a much larger flat screen and are high definition and are clearer than your old one. The signals are digital now.
I have never seen an old TV that has a picture tube covered with your "safety glass". Why does your old TV need a "safety glass"?

What is the goal? To use the TV as a decorative piece and you just want to protect it from a Tonka truck being thrown at it by a grand kid? Or do you expect to watch the TV again.

Also, what is the origin of that protective lens cover you are showing. Is it an original protective piece covered with old adhesive or is it a new piece with a protective film on it?

if you want to bond it directly to the glass and watch the Tv, you'll need to remove all of the old adhesive until the piece is clear, then use an optically clear adhesive (Look for Liquid Optically Clear adhesive (LOCA). Youll need to apply significan excess with a high point in the center of your convex surface and a fixture to push the outer lens into place. The outer lens should contact in the center first and push adhesive to the edges without trapping any air. The fixture is needed to apply pressure evenly - the adhesive is viscous and pressure can crack or distort the outer lens or crack the picture tube.

audioguru said:

Is your antique TV 20 years old or more?
TVs for the last 10 years have a much larger flat screen and are high definition and are clearer than your old one. The signals are digital now.
I have never seen an old TV that has a picture tube covered with your "safety glass". Why does your old TV need a "safety glass"?

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This is a 1968 RCA with vacuum tubes in it. And yes it was a common practice back then for them to put safety glass on these type of picture tubes. Usually the glue behind them would turn green and it would be something like a cataract the way they would call that greenish look.

That's why I had to do something like this to this receiver.

gophert said:

What is the goal? To use the TV as a decorative piece and you just want to protect it from a Tonka truck being thrown at it by a grand kid? Or do you expect to watch the TV again.

Also, what is the origin of that protective lens cover you are showing. Is it an original protective piece covered with old adhesive or is it a new piece with a protective film on it?

if you want to bond it directly to the glass and watch the Tv, you'll need to remove all of the old adhesive until the piece is clear, then use an optically clear adhesive (Look for Liquid Optically Clear adhesive (LOCA). Youll need to apply significan excess with a high point in the center of your convex surface and a fixture to push the outer lens into place. The outer lens should contact in the center first and push adhesive to the edges without trapping any air. The fixture is needed to apply pressure evenly - the adhesive is viscous and pressure can crack or distort the outer lens or crack the picture tube.

Click to expand...

The television is currently undergoing what you might call major electronic surgery on the color chroma board. I put a lot of new parts in this including a brand new high voltage flyback coil.

The TV was in working condition until I started having problems with the color on it. I've almost got this job done too. The only thing that's been hard was having to tag and cut 44 wire connection was on that circuit board. Certainly not a job I want to go through again that's for sure

ronsimpson said:

My memory is not good. I think we used a vacuum chamber to suck out the air bubbles in the adhesive.

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That's what has me wondering about attempting to put any kind of adhesive under there. If I can't get the air bubbles out then I may not even be able to put that on there.

Other than a safety issue without it I'm not too worried about it at this point. I'll just be happy once I get all the electronic stuff repaired inside and have the TV working again

gophert said:

What is the goal? To use the TV as a decorative piece and you just want to protect it from a Tonka truck being thrown at it by a grand kid? Or do you expect to watch the TV again.

Also, what is the origin of that protective lens cover you are showing. Is it an original protective piece covered with old adhesive or is it a new piece with a protective film on it?

if you want to bond it directly to the glass and watch the Tv, you'll need to remove all of the old adhesive until the piece is clear, then use an optically clear adhesive (Look for Liquid Optically Clear adhesive (LOCA). Youll need to apply significan excess with a high point in the center of your convex surface and a fixture to push the outer lens into place. The outer lens should contact in the center first and push adhesive to the edges without trapping any air. The fixture is needed to apply pressure evenly - the adhesive is viscous and pressure can crack or distort the outer lens or crack the picture tube.

Click to expand...

Oh and one other thing I wanted to mention, that glass is actually a safety glass for the c r t. I had removed the old one but it accidentally got broken in the process. So a replacement was needed.

Also just to follow up what you were mentioning about "using it as a prop", well the answer is no I'm not doing that here. I actually represent groups on the internet who are in the business of servicing and restoring antique and vintage television receivers such as this one.

Usually I will resell them once I get them all fixed up. I'm actually going to be holding on to this one after I get everything done to it. I just hope everybody enjoys seeing the fruition of the creativity of my work which was once carried on by my late father.

Since I don't plan on being on this site too much longer in the future.

Rebuff said:

Since I don't plan on being on this site too much longer in the future.

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We'd be saddened to lose such a new member before we get the benefit of their charm and willingness to share what they know with other members.

I thought that we had been to Bedlam and back with this topic just a few short months ago:


Do we have to go there again?

JimB

gophert said:

We'd be saddened to lose such a new member before we get the benefit of their charm and willingness to share what they know with other members.

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Yes I know what you mean. And I hate to have to be the one to do this. I'm just like anybody else who maybe getting curious and wants to know all the answers before I start working on something.

And sometimes I forget some of the answers if they were given to me months ago. I just don't think I can take anybody else on public forums too much.

And most everybody on Facebook for those that I've been doing this kind of work for a long time. I've actually had requests from other people out there wanting me to either repair or restore their antiques.

I also had a similar predicament when I used to be a karaoke singer. And I had got back into doing that after my parents died since my mom was in full support of it.

But it just happened to be I had words with a local musician in the area. It got to the level where I told him a few things I didn't like about his singing. Next thing you know he opens up a Spam account and he starts threatening me saying he was going to take care of me he was coming after me.

Next thing you know, I actually lost the friendship I once used to have with the DJ I sang for. So I ended up getting out of singing in clubs and I don't do it anymore. In that case it was a matter for my own personal safety that I had to stop doing it all together.

I figured by now I've got all the answers I need and I just want to be left alone. Really don't want anybody else bothering me anymore. But it was glad that I got to know everybody and I appreciated all the advice

My first TV was a 27" Philips that was made in 1971 in the local car radio factory where I worked. It was replaced in 1997 by a Sony with a 31" CRT.
I got my first 55" flat screen 4k "smart" TV almost 2 years ago.

audioguru said:

My first TV was a 27" Philips that was made in 1971 in the local car radio factory where I worked. It was replaced in 1997 by a Sony with a 31" CRT.
I got my first 55" flat screen 4k "smart" TV almost 2 years ago.

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And I know the flat screen televisions have been quite the rage ever since the manufacturing of CRTs went by the wayside years ago. I can't even remember when I had bought one of the last CRT televisions from the local Walmart store before they stop selling them.

And I've always liked working on these old vacuum tube televisions ever since I grew up watching my late father work on those kind of receivers. And as I said on previous posts, my father was a 32-year electrical lineman in the mill. Dangerous job.

He never wanted me to follow in his footsteps in that line of work. He wasn't too bad with working on televisions either. But sometimes he made some costly mistakes when working on them.

He was a great man and I really miss him ever since you passed away back in 2008. Having some of these old televisions around the house that I don't sell is one way of me holding onto a memory of him.

Rebuff said:

I'm just trying to figure out what kind of stuff you're supposed to use on a picture tube safety glass like this

Click to expand...

I'd look at a UV-curing glass adhesive, as used to repair car windscreens.

Use rather more than you need, with the safety glass arranged face down on a padded support with a pool of adhesive in it, and lower the CRT in to that (or lift it to the CRT) - so any bubbles are squeezed out the sides along with excess adhesive.

You would have to make some kind of support rig for the CRT and be able to use a UV light to cure as much adhesive as possible in place, after the excess spill had been cleaned up, then support only by the tube and cure the rest that was previously hidden.
Cure for several times longer than the adhesive makers minimum time, just to be sure it's all 100% set.

Not easy but I can't think of any other way of avoiding or at least minimising bubbles without a vacuum chamber - and UV cure adhesive means you can avoid anything setting before you are ready.

The other option would be to get a piece of flat plate glass the same size as the outside of the CRT bezel and attach that externally.
That's what TVs generally had prior to the integrated implosion guard.

rjenkinsgb said:

The other option would be to get a piece of flat plate glass the same size as the outside of the CRT bezel and attach that externally.
That's what TVs generally had prior to the integrated implosion guard.

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And was a regular job, trying to clean between the glass and the CRT

It also made replacing the CRT quite difficult, and we even had a 'jig' (piece of wire hanging from the ceiling ) to hold the chassis out of the way for one specific model (I 'think' it was an Ekco?).

But as in his previous thread, I've never heard of anything so crazy as removing the integral safety glass.

This is an amazing thread, really. I have 2 TV's with channel 1 and really don;t know what to do with them. One is an RCA tabletop with a domed top. The other is stand-alone with a blue bubble magnifier screwed to the TV.

KeepItSimpleStupid said:

This is an amazing thread, really. I have 2 TV's with channel 1 and really don;t know what to do with them. One is an RCA tabletop with a domed top. The other is stand-alone with a blue bubble magnifier screwed to the TV.

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Look on the bright side, at least you can still generate a signal to feed them (DTT box etc.) as they will be 525 line. The old British sets were 405 line, and we upgraded to 625 line a very long time ago - there have been small numbers of 625/405 converters (for enthusiasts), but they were expensive and seem to have long since disappeared.

A CVBS input to NTSC modulator still exists: https://www.ambery.com/md211.html

A step in the right direction.

Rebuff said:

And yes it was a common practice back then for them to put safety glass on these type of picture tubes.

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according to the RCA Receiving Tube data book... the tube has safety feature "D", which is "Integral Safety Panel (Laminated)" https://archive.org/details/RCA_RC-30_1975/page/n667/mode/2up the tube data is on page 667, the notes listing the safety feature codes is on page 670 i worked as a tech in several TV shops when i was young, and we never replaced the safety glass, the tube came with it bonded to it, and we never had to mess with it.
and it's not bonded on with necessarily just an adhesive, but also a layer of stretchy plastic with adhesive on both sides, similar to what's in an automobile windshield.

I found the process"
devitrifying frit or solderglass seal
developed by Corning Glass Works in 1958
A toothpaste like material composed of glass/ceramic applied to junction to be sealed
it fuses under high temperature and pressue and removed with Nitric acid

Bibliography:
The cathode ray Tube
technology, history and applications
by Peter A Keller