About a month ago or more I accidently cracked a 12BA6 tube. The crack was small. No air leaked in, however. I drizzled a little super glue over the crack to keep it from spreadding. It still works very well, though the radio it is in I use rarely. When I do use the radio, though, it is usually on for several hours at a time.

I also have a 35W4 with a small crack, similar to above. That is what happens when I store a bunch of tubes in a box, unorganized or padded. I did the same with it that I did with the 12BA6. It still works well, though I rarely use it. I wonder if the crack would eventually spread if I cycled the tube a lot.

T.

:About a month ago or more I accidently cracked a 12BA6 tube. The crack was small. No air leaked in, however. I drizzled a little super glue over the crack to keep it from spreadding. It still works very well, though the radio it is in I use rarely. When I do use the radio, though, it is usually on for several hours at a time.
:
:I also have a 35W4 with a small crack, similar to above. That is what happens when I store a bunch of tubes in a box, unorganized or padded. I did the same with it that I did with the 12BA6. It still works well, though I rarely use it. I wonder if the crack would eventually spread if I cycled the tube a lot.
:
:T.

I remember reading somewhere that superglue was a "no-no" for regluing loose tube bases. Something about differing/incompatible coefficients of expansion that would cause the envelope to shear off at the base. I would think the incompatibilities would also apply to fixing cracked glass envelopes as well and hasten the cracking process. This may possibly be 'urban legend' however. Personally, I have used a bit of the stuff to tighten up bases on tubes that get hot without a problem. See this link and make up your own mind:
http://www.vintage-radio.net/forum/showthread.php?t=400

I have used super glue so many times to secure tube bases. I have used it to secure grid caps, too. The only problem I have ever had with super glue is that it is a form of plastic, and with really hot tubes, the grid caps come loose again sometimes. Also, with heat, super glue will temporarily give off a nasty fume that can really burn your eyes. The same can happen, though, if you get it wet or mix it with something that reacts with it.

I know of one other experience that had nothing to do with super glue, but rather one of those all-in-one phono-8-track-radio combos. I had one all the time when I was around 10 (I was given my first one when I was about 8, and I think I had one until I was about 14...a lady kept giving them to me...not sure where she got them from...but when I'd break one, I'd get another). At any rate, the phonograph start-reject lever broke off, so I decided to melt a piece of metal to the remains of the lever. Good God! The fumes that plastic gave off almost made me blind! It was terrible!

Thomas

Thomas:
I heard that getting too "personal" with a reject lever can lead to blindness

:Thomas:
:I heard that getting too "personal" with a reject lever can lead to blindness

Peter: Breaking off one's reject lever is even a worse predicament... and melting it back together - he's tough as nails! Perhaps the poor boy should get out and about more often... An interesting, but useless note: heated cyanoacrylic fumes are used to 'develop' fingerprints from crime scene objects. Of course a ventilated hood is employed in the process.

It works well, too. Sometimes super glue can leave a nasty white haze all over the surrounding area while it cures.

T.

heated cyanoacrylic fumes are used to 'develop' fingerprints from crime scene objects. Of course a ventilated hood is employed in the process.

:I remember reading somewhere that superglue was a "no-no" for regluing loose tube bases.
:This may possibly be 'urban legend' however.

Is is _not_ an urban legend.

Tubes may break, cleanly, at the base if cyanoacrylate glue a.k.a. super glue is used to secure a loose base. The thread you supply explains well the phenomenon.

::I remember reading somewhere that superglue was a "no-no" for regluing loose tube bases.
::This may possibly be 'urban legend' however.
:
:Is is _not_ an urban legend.
:
:Tubes may break, cleanly, at the base if cyanoacrylate glue a.k.a. super glue is used to secure a loose base. The thread you supply explains well the phenomenon.

Z: Proof is in the pudding. I have used it to secure loose bases for a decade or so and have not had a problem - even in hot-running rectifier and output tubes used on a prolonged/continuous basis. Perhaps I'm not applying as much as those who describe the phenomenon. I use a spot or 2 and don't drown the base in it. Watson

I do drown the base in it, and I have no troubles.

T.

:I do drown the base in it, and I have no troubles.
:
:T.

Fine. We're all idiots. Sorry for intruding.

I guess anyone securing a crack (?) in a tube with super glue knows more than I.

I sure enjoyed the reading though.

::I do drown the base in it, and I have no troubles.
::
::T.
:
:Fine. We're all idiots. Sorry for intruding.
:
:I guess anyone securing a crack (?) in a tube with super glue knows more than I.
:
:I sure enjoyed the reading though.

Watson & Thomas,
Don't mind "Z" - obviously he has missed his medication. I have read over some of his previous posts and he seems to be a rather disagreeable chap - close-minded & open only to his view of things. He is, as the French would say, 'a moron'.

Ha! Z is pretty cool. ...Knows a lot, too. ....Just tempermental. That's all.

I've been amazingly level headed lately. Sometimes I get tempermental. I go through phases...almost like a woman. Sorry ladies. Don't know of too many on here, but I apologize, anyway. You know what I'm talking about.

T.

:Watson & Thomas,
: Don't mind "Z" - obviously he has missed his medication. I have read over some of his previous posts and he seems to be a rather disagreeable chap - close-minded & open only to his view of things. He is, as the French would say, 'a moron'.

________________________________________________________________________

Don't discount what "Z" has to say, he is one of the most knowledgeable people on this forum, and name calling,I think you are on the wrong forum, we don't do that here. And no email address, what do you have to hide Mr Q. No guts no glory.

And getting back to the subject. I have had tubes break clean at the base after using super glue. It has been on tubes that run very hot and I did glue all around the base.

Dave

I suppose that if the super glue holds strong, the tube could crack off from expansion. The old style of glue would get soft if heated a lot. That is why ordinary light bulbs cannot be used in an oven. The glue gets soft, and the bulb drops out. In a tube atmosphere, though, usually those temperatures are never reached, and usually the tubes are vertical, so if the glue melts, the tube doesn't go anywhere....it just gets loose in its base.

Makes sense to me. Still, I have not had a tube crack. I hope I never do, either.

T.

ALL,
Don't wanna get into the fracus, because I've been extremely successful with all my attempts using super glue, to attach my fingers to themselves and some inanimate objects as well. Its great, just so fluid, that it flows to all the unwanted places, but alas, I see a need for super glue mask. Film at 11.

marv

:
::Watson & Thomas,
:: Don't mind "Z" - obviously he has missed his medication. I have read over some of his previous posts and he seems to be a rather disagreeable chap - close-minded & open only to his view of things. He is, as the French would say, 'a moron'.
:
:________________________________________________________________________
:
:Don't discount what "Z" has to say, he is one of the most knowledgeable people on this forum, and name calling,I think you are on the wrong forum, we don't do that here. And no email address, what do you have to hide Mr Q. No guts no glory.
:
:And getting back to the subject. I have had tubes break clean at the base after using super glue. It has been on tubes that run very hot and I did glue all around the base.
:
:Dave

Marv et al:
I have found that the "brush on" more viscous type works really well for me.
Stays where I want it and I can control; where I put it.
And un-like the really older type that I think I remember.. where you had to have only ultra-clean surfaces and hold them under pressure for a moment... this new stuff holds even if you just let it fill a void.

By the way... did you guys also know that a little super glue dropped on some baking soda in a void will fill it hard like body putty?
Baking soda is an accelerator of sorts... makes this stuff into a rock hard mass.

Peter,
Yes I've heard of the baking soda filler, and strangely enough a neighbor modeler purchased some powder at a hobby store to do just that. It was a dry powder of sorts, but very small spheres, with a name including the word "balls", and I'd guess $5 an oz.

marv

:Marv et al:
:I have found that the "brush on" more viscous type works really well for me.
:Stays where I want it and I can control; where I put it.
:And un-like the really older type that I think I remember.. where you had to have only ultra-clean surfaces and hold them under pressure for a moment... this new stuff holds even if you just let it fill a void.
:
:By the way... did you guys also know that a little super glue dropped on some baking soda in a void will fill it hard like body putty?
:Baking soda is an accelerator of sorts... makes this stuff into a rock hard mass.

:Don't discount what "Z" has to say, he is one of the most knowledgeable people on this forum, and name calling,I think you are on the wrong forum, we don't do that here. And no email address, what do you have to hide Mr Q. No guts no glory.

_______________________________

Dave,
I do believe it was "Z-" who started the name calling referring to us as "all idiots". I have nothing to hide and would have preferred to express my feelings with "Z-" privately - but he, however, does not divulge his email address either - so why should I? It is really quite irritating to have to worry about someone with a treasure-trove of rude comments lurking about this most excellent forum waiting for a moment to pounch on those with lesser knowledge. I dare say he would be banned from most other forums. That's all I have to say in this matter.

Q-

:::I do drown the base in it, and I have no troubles.
:::
:::T.
::
::Fine. We're all idiots. Sorry for intruding.
::
::I guess anyone securing a crack (?) in a tube with super glue knows more than I.
::
::I sure enjoyed the reading though.
:
:Watson & Thomas,
: Don't mind "Z" - obviously he has missed his medication. I have read over some of his previous posts and he seems to be a rather disagreeable chap - close-minded & open only to his view of things. He is, as the French would say, 'a moron'.

Q: In my near 70 years, I have learned to overlook such people. It just isn't worth the effort to get worked up over. True wisdom requires intellegence infused with humbleness and tolerance. Intellegence with arrogance is soon forgotten. Watson

::::I do drown the base in it, and I have no troubles.
::::
::::T.
:::
:::Fine. We're all idiots. Sorry for intruding.
:::
:::I guess anyone securing a crack (?) in a tube with super glue knows more than I.
:::
:::I sure enjoyed the reading though.
::
::Watson & Thomas,
:: Don't mind "Z" - obviously he has missed his medication. I have read over some of his previous posts and he seems to be a rather disagreeable chap - close-minded & open only to his view of things. He is, as the French would say, 'a moron'.
:
:
:Q: In my near 70 years, I have learned to overlook such people. It just isn't worth the effort to get worked up over. True wisdom requires intellegence infused with humbleness and tolerance. Intellegence with arrogance is soon forgotten. Watson

Wow, did this discussion ever go downhill. Is it a full moon or just All Hallows Eve?

Mike M.

Mike,
Judging by the postings, it would seem both.

marv

:::::I do drown the base in it, and I have no troubles.
:::::
:::::T.
::::
::::Fine. We're all idiots. Sorry for intruding.
::::
::::I guess anyone securing a crack (?) in a tube with super glue knows more than I.
::::
::::I sure enjoyed the reading though.
:::
:::Watson & Thomas,
::: Don't mind "Z" - obviously he has missed his medication. I have read over some of his previous posts and he seems to be a rather disagreeable chap - close-minded & open only to his view of things. He is, as the French would say, 'a moron'.
::
::
::Q: In my near 70 years, I have learned to overlook such people. It just isn't worth the effort to get worked up over. True wisdom requires intellegence infused with humbleness and tolerance. Intellegence with arrogance is soon forgotten. Watson
:
:Wow, did this discussion ever go downhill. Is it a full moon or just All Hallows Eve?
:
:Mike M.

I didn't even think that anyone was going to reply. I almost didn't post this subject (I almost deleted what I wrote), though I thought that perhaps someone would take interest in it. WOW!

At any rate, to-day is All Saints Day, so we can rest at last.

T.

:I didn't even think that anyone was going to reply. I almost didn't post this subject (I almost deleted what I wrote), though I thought that perhaps someone would take interest in it. WOW!
:
:At any rate, to-day is All Saints Day, so we can rest at last.
:
:T.

I have taken my medication and finished baying at the moon last night so feel safe posting. I think the problem may be the same as with the halogen light bulbs. Where the glass gets so hot any foreign substance on the surface may form a hot spot and the bulb cracks. If even the oil from your fingers can do it on the halogen bulbs what would a blot/blob of super glue do? The reason for the mixed results may lie in the heat that the differant radio tubes generate. The hotter running ones being more susceptible to popping. I realize halogen bulbs get a lot hotter (found that out going to remove one)then radio tubes but principle may be the same. By the way if you get a crack in the glass chances are air (oxygen) has gotten into the tube and though it may last a while if it didn't get a lot in, its going to burn up the heater prematurely. PL

On the note of burning up the heater, when air leaks into a tube, the heater will not burn up unless the heater voltage is increased. Vacuums do not conduct heat. As air gets into the tube, the filament will become dimmer and dimmer, and when at atmospheric pressure, will not light at all at normal voltage. The air will cool the filament too much. If you increase the voltage enough to light it, it will light up and burn out eventually. If you turn it off, you will notice it cool quite rapidly...not slowly like tubes normally cool.

The reason why a lightbulb stays lit at normal voltage when you break it, and why it burns up, is because modern light bulbs (since about 1910) are filled with a gas. The filament is designed to run under this condition (if you were to run it at the same voltage in a vacuum, it would actually burn out). Exposing it to air has a cooling effect similar to the inert gas. It glows about the same brightness (the gas is under less pressure, so there isn't as much of it). The only problem is that air contains oxygen, and so the filament burns out. The reason why modern bulbs are filled with gas is because the filament can be lit brigher than in a vacuum, where the filament would vaporize under such low pressure. You will notice that the filament in old vacuum bulbs is quite spread out. In gas bulbs it is quite compact. Otherwise convection currents within the bulb would cool the filament too much. Vacuum bulbs also do not get as hot as their gaseous friends.

T.

:Dave,
:I do believe it was "Z-" who started the name calling referring to us as "all idiots".

Funny. The comment was meant toward me and all those to whom tube breaking at base happened because of super glue. In French it is called a "brocard". Unless it happened to you too ?

BTW, you know _exactly_ who I am and how to contact me, but then you'd reveal who you are.

If you really want to insult someone, at least know your facts. Being a Moron isn't that bad, it's one step up from an imbecile and two steps up from an idiot on the Binet scale and is NOT a French word. It was a term coined by H. Goddard (American psychologist) from the Greek word Moros.

Watson: Yeah, I suppose it's all in the pudding. Most breaks did happen after "drowning" the base with super glue as per other's bad experience), but it did happen to me using only a few drops. I recall it was a small ST tube (ST-16). It is well documented if you do a little search using google. Now just because something never happened to someone doesn't mean it is not possible or is a lie. I share my experience and I find it quite annoying to have people say, "well, it never happened to me, so...".

Are we having fun yet ?

::Dave,
::I do believe it was "Z-" who started the name calling referring to us as "all idiots".
:
:Funny. The comment was meant toward me and all those to whom tube breaking at base happened because of super glue. In French it is called a "brocard". Unless it happened to you too ?
:
:BTW, you know _exactly_ who I am and how to contact me, but then you'd reveal who you are.
:
:If you really want to insult someone, at least know your facts. Being a Moron isn't that bad, it's one step up from an imbecile and two steps up from an idiot on the Binet scale and is NOT a French word. It was a term coined by H. Goddard (American psychologist) from the Greek word Moros.
:
:Watson: Yeah, I suppose it's all in the pudding. Most breaks did happen after "drowning" the base with super glue as per other's bad experience), but it did happen to me using only a few drops. I recall it was a small ST tube (ST-16). It is well documented if you do a little search using google. Now just because something never happened to someone doesn't mean it is not possible or is a lie. I share my experience and I find it quite annoying to have people say, "well, it never happened to me, so...".
:
:Are we having fun yet ?

_______

Z: Whoa now... I don't have a dog in this fight. A forum like this should be to express and exchange ideas and experiences, not a bully pit for name-calling and strong wills. I believe we all have expertise and experience in different areas that deserve to be heard without being put down. Let's all be civil here. Any disagreements or ego clashes should be handled privately. Watson

Poor Watson,

You are wasting your words dear man (or more precisely, your bits and bytes). Until Big Brother mandates Prozac in the water supply - we will have to continue to endure passive-aggressive bipolarism such as this. To acknowledge maniacal egotism only fuels its fire.

Q-

::Watson: Yeah, I suppose it's all in the pudding. Most breaks did happen after "drowning" the base with super glue as per other's bad experience), but it did happen to me using only a few drops. I recall it was a small ST tube (ST-16). It is well documented if you do a little search using google. Now just because something never happened to someone doesn't mean it is not possible or is a lie. I share my experience and I find it quite annoying to have people say, "well, it never happened to me, so...".
::
::Are we having fun yet ?
:
:_______
:
:Z: Whoa now... I don't have a dog in this fight. A forum like this should be to express and exchange ideas and experiences, not a bully pit for name-calling and strong wills. I believe we all have expertise and experience in different areas that deserve to be heard without being put down. Let's all be civil here. Any disagreements or ego clashes should be handled privately. Watson

:About a month ago or more I accidently cracked a 12BA6 tube. The crack was small. No air leaked in, however. I drizzled a little super glue over the crack to keep it from spreadding. It still works very well, though the radio it is in I use rarely. When I do use the radio, though, it is usually on for several hours at a time.
:
:I also have a 35W4 with a small crack, similar to above. That is what happens when I store a bunch of tubes in a box, unorganized or padded. I did the same with it that I did with the 12BA6. It still works well, though I rarely use it. I wonder if the crack would eventually spread if I cycled the tube a lot.
:
:T.

Thomas - I'll bet you never realised how appropriate the title of your thread would come to be. "Two cracked tubes" sums it up rather perfectly. Regards, Hal