[Sherwood]

So, I learned that tubes are to ba handled with kid gloves, since sebacious oil can create temperature irregularities in a tube that shorten its life. that sounded pretty legit to me, until I went to a head fi meet.

Mikhail from singlepower, pretty much the tube guru of the known world whose company has the second largest stock of NOS tubes, just grabs them and pulls with his bare hands. No gloves, no gentle rocking, just in and out.

Do you think this is sort of how new parents handle their kids like little bubbles of glass, while maternity nurses treat babies like beanbags? Which is the proper way?

 

[Uncle Erik]

All the action goes on inside the tube and you can't touch that. Handling them doesn't hurt them, either. I've dug many out of boxes at hamfests and they're just fine. Still, I usually wipe them off or remove dust with a brush. No harm in that.

 

[F107plus5]

When I played a lot with tubes in the 50s and 60s it was just a pull and replace with bare hands(or tube pullers if they were still too hot). Never a thought to cleanliness or operating problems since tubes were cheap and wore out all the time and, most importantly, hidden in a box! And after all adjustments were used up they were simply yanked, tossed out and replaced.

Nowadays, tubes are expensive and......"exposed".....like fine audio jewelery! In a place of supreme reverence as the showpiece of our equipment. Glowing in their majesty, demanding to be pampered and treated with the utmost respect they deserve!

...or something like that.

 

[KYTGuy]

Projection lamps, with their very high temperatures, forced cooling, and quartz glass envelopes, are running just a few tens of degrees from imploding against atmospheric pressure when they are in use, and they are subject to stress failures from uneven heating and cooling, so they are the ones that you must either handle with gloves/pullers, or clean with alcohol after you touch them with bare hands. Any oils/schmutz on the envelope will burn to a char, and then alter the thermal profile/stress the glass.

Vacuum tubes are very rarely driven to those temperatures, almost never in audio useage. It is OK to handle ambient cooled vacuum tubes with bare hands, IF THEY ARE COOL, and skin oils will seldom cause a problem, even if it chars. I have seen many audio tubes in service with a quarter inch of grey fur (dust) in operation for many years in that condition. The only special case where the handling regime listed above for Projection bulbs is required for electronic vacuum tubes is when they are operated with forced cooling (dedicated cooling fans, with chimneys and supply/exhaust hoses attached to the chimneys).

All glass tubes are subject to failure if scratched, dropped, or hit with thermal shock. So, don't allow any sudden liquid contact of any kind while they are hot, do store them each separately when they are not in a socket, and don't allow high accelerations.

Don't apply twisting forces on the pins while inserting or removing.

Don't operate them in excess of their power, frequency, voltage, or thermal limits. If you push them too hard, you get X-rays, Fires, unwanted heat, and very poor service life.

 

[tjkurita]

Yes. Let's not forget about the military and industrial applications for tubes during their heyday. I can't imagine the tubes used during the Korean war were handled with kid gloves. And these are the same tubes we pay very high dollar for today.

Having said that, I never pull tubes by the glass. I always use the base to move them or change them. Also, I always use a micro-fiber cloth to handle them.

I guess it's about preference, but it doesn't hurt to treat them nicely when you only handle them occasionally. A guy like Mikhail would spend his entire day polishing tubes if he concerned himself with that kind of stuff. He wouldn't have time to build any amps. Of course, he handles tubes all day long.

 

[mrarroyo]

I usually try to wait a couple of minutes to let them cool off a bit. Then I jus use my fingers to pull them off. If stuburn an bit of rocking may help.

 

[nelamvr6]

Quote:

Originally Posted by Uncle Erik /img/forum/go_quote.gif All the action goes on inside the tube and you can't touch that. Handling them doesn't hurt them, either. I've dug many out of boxes at hamfests and they're just fine. Still, I usually wipe them off or remove dust with a brush. No harm in that.

Concur, but I still wipe mine off with tech grade isopropyl alcohol just in case. You know, peace of mind etc.

 

[warubozu]

As mentioned previous I too just use my bare hands to remove my tube. Also employ a gentle rocking motion if the tubes are tight in their sockets. I also gently wipe the glass envelopes on the tube with a dry clean cloth after touching them.

 

[ken36]

I wouldn't worry, If I were you.

 

[mb3k]

Quote:

Originally Posted by nelamvr6 /img/forum/go_quote.gif Concur, but I still wipe mine off with tech grade isopropyl alcohol just in case. You know, peace of mind etc.

Isopropyl alcohol works wonders on NOS tubes. I usually use make-up pads and rub the tube gently to get off the grime. Time to get Deoxit for the filthy pins.
A glasses cleaner cloth works well to handle tubes.

 

[nelamvr6]

Quote:

Originally Posted by mb3k /img/forum/go_quote.gif Isopropyl alcohol works wonders on NOS tubes. I usually use make-up pads and rub the tube gently to get off the grime. Time to get Deoxit for the filthy pins. A glasses cleaner cloth works well to handle tubes.

Yep, I used Deoxit on my tube (I only have the one), but I don't think it was really necessary. It's NOS, but it has gold pins.

But once again, peace of mind etc.

 

[Tech2]

I used to use cotton gloves, especially after reading the description for the Millett Hybrid amp at Headroom, which says to 'slip on cotton gloves or use a tissue' when tube rolling. Now I just use my bare hands and wipe off the tubes after handling them, merely for aesthetic reasons. Greasy fingerprints just look bad.

 

[Tech2]

Quote:

Originally Posted by nelamvr6 /img/forum/go_quote.gif Yep, I used Deoxit on my tube (I only have the one), but I don't think it was really necessary. It's NOS, but it has gold pins. But once again, peace of mind etc.

Which Deoxit product do you guys use? I went to their website and found waaaaay to many choices. A recommendation would be much appreciated.

 

[nelamvr6]

Quote:

Originally Posted by Tech2 /img/forum/go_quote.gif Which Deoxit product do you guys use? I went to their website and found waaaaay to many choices. A recommendation would be much appreciated.

I just use the standard garden variety DeoxIT, I have used it for decades, from back when it was still called Cramolin.

 

[Tech2]

Quote:

Originally Posted by nelamvr6 /img/forum/go_quote.gif I just use the standard garden variety DeoxIT, I have used it for decades, from back when it was still called Cramolin.

Like this one?