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Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 193

post #2881 of 7298

Dunno if anyone else had this issue, but I broke 2 6AV6 tubes so far cutting pins. The base cracked one one of my RCA and one of my Sylvania.

post #2882 of 7298

Was trying to find a way to clean the pins first i tried with a plastic  pill  container took and old tube heated it up and press the tube against the plastic lid and the heated steel pins poked thru the thin plastic lid and on a large container i could clean up to 4 tubes at a time the problem is finding the right material to clean the pins efficiently i used regular sand and a fast moving rock and roll tune to help me along but doesnt do a good job would have to try that silicon carbide Troll Dragon was talking about but what i found and works very good is a rubber coated tapered bit it goes everywhere and removes all the dirt ,does a great job but doesnt last foreever compared to a sandlike substrate.

                                                                                                                                                                                              

post #2883 of 7298
Quote:
Originally Posted by mab1376 View Post
 

Dunno if anyone else had this issue, but I broke 2 6AV6 tubes so far cutting pins. The base cracked one one of my RCA and one of my Sylvania.

 

I have cut probably 15 pairs so far and never had this happen....  Perhaps your cutters are a bit dull?

post #2884 of 7298
Quote:
Originally Posted by mab1376 View Post
 

Dunno if anyone else had this issue, but I broke 2 6AV6 tubes so far cutting pins. The base cracked one one of my RCA and one of my Sylvania.

 

I broke a 6j4s cutting the pins the pin next to the one i was cutting broke off it was bent a little brought it back as i to with all bent pins but this time it broke crap thats one pair i wont be trying. Ya Super its your pair. might as well show you a picture of those nice looking tubes wont see them again. First time i broke one also and it had to be those was looking forward to listening to those tubes


Edited by MIKELAP - 9/11/13 at 6:56am
post #2885 of 7298
Quote:
Originally Posted by gibosi View Post
 

 

I have cut probably 15 pairs so far and never had this happen....  Perhaps your cutters are a bit dull?

 

They're brand new blue point lead snippers. They're ridiculously sharp. I had no issue on gold pins.

 

Luckily it only happened to one of my 3 RCA tubes, but I only had 2 sylvanias so i no longer own a pair.

 

I also covered the pin with a cloth so it wouldn't go flying away, maybe that caused it to resonate the impact into the glass?

post #2886 of 7298
Quote:
Originally Posted by mab1376 View Post
 

 

They're brand new blue point lead snippers. They're ridiculously sharp. I had no issue on gold pins.

 

Luckily it only happened to one of my 3 RCA tubes, but I only had 2 sylvanias so i no longer own a pair.

 

I also covered the pin with a cloth so it wouldn't go flying away, maybe that caused it to resonate the impact into the glass?

 

I can't imagine that covering the pin with a cloth would cause this.... Perhaps cutting the pin aggravated a pre-existing small internal stress fracture in the glass....

 

Going forward, I guess we should just assume that there is always a chance this will happen. And I have just been very lucky so far. :)

post #2887 of 7298
The dremel with a small cutoff disk should snick those pins off rather quickly and without much stress. Dremel's can get away from you really quickly though if you are not careful. biggrin.gif
post #2888 of 7298
@MIKELAP What dremel speed did you run the rubber tip at to clean up the pins? I can see that going wrong quickly with bent pins everywhere...

I shall have to try this method as well, even though the carbide does work satisfactory.
post #2889 of 7298
Quote:
Originally Posted by TrollDragon View Post

@MIKELAP What dremel speed did you run the rubber tip at to clean up the pins? I can see that going wrong quickly with bent pins everywhere...

I shall have to try this method as well, even though the carbide does work satisfactory.

Maximum speed and  its pretty safe of course if your not confortable with Dremel's dont try it. 

 

Heres a picture of the two, bit is pretty small


Edited by MIKELAP - 9/12/13 at 12:24pm
post #2890 of 7298

thanks for clearing this up for me.

post #2891 of 7298
Thanks MIKELAP!
Is that a Dremel brand bit or a Princess Auto / Canadian Tire version? I might just have to stop in at PA on the way home... biggrin.gif
post #2892 of 7298

TALES FROM THE SAND BOX OR THE BEST WAY TO CLEAN TUBE PINS

 

Decided to do an experiment on cleaning tube pins with available means, i.e. no cost involved. First I snuck out to the local playground and scooped up half a plastic cup of playground sand. The big stuff in the cup are pieces of wood mulch.

 

 

 

After manual cleaning of the sand, some of it was poured into a shot glass:

A pin shield was made out of an old CD mailer. The holes were made pressing the tube against the paper, then marking the indentations and piercing with a small awl. (Will Amazon pay me royalties?)

Selected two corroded tubes from my 6AK5 collection. The tube with the blue bottom plate is a Crosley (RCA) from January 1952 and the clear bottom plate is a Tung Sol from January 1954. This is the BEFORE picture:

 

The plan was to use a rubber finger grip and turn the Crosley tube inside the sand of the shot glass for one minute in each direction. The second part of the experiment was to use an alternative cleaning method as a comparison of effectiveness - more later.

 

This is a picture of a rare cactus. No, it's not a Barrel Cactus, but a Yellow Nib Tube Cactus (Croslesia Audiophilia Nervosa)

Here is an action shot of tube turning using the pin shield (finger grip removed for clarity)

The alternative method of pin cleaning has been exhaustively described in the literature as scraping the pins with something somewhat sharp. What could be more appropriate than a historically correct 1950's pocket knife?


Wait, what's that inscription on the bottom of the blade?

Well, having squinted over countless tubes trying to read invisible markings, this is a piece of cake: It reads: Colonial. Prov USA 492. Obviously, (with a little help of our Google friends) this knife was manufactured by the Colonial Knife Co of Providence, Rhode Island, USA the second week of 1949. (Actually, since this is not an EIA tube, maybe 492 is a model number? )

 

In the interest of scientific exploration, we continue: The blue bottom tube was cleaned with the shot glass method, and the clear bottom tube with the pocket knife: This is the AFTER picture:


Looking at the picture, neither tube is sparkling clean. Looking at the before picture (4th picture) there is a definitive improvement; maybe the Crosley cleaned with sand is a little cleaner. However, the sand thing is cumbersome and tedious; the scraping is much faster and easier. What really counts is the electrical contact. If the scraping does not help the first time, I can always look for spots and do a little more.

 

Verdict: Colonial wins

post #2893 of 7298
Quote:
Originally Posted by TrollDragon View Post

Thanks MIKELAP!
Is that a Dremel brand bit or a Princess Auto / Canadian Tire version? I might just have to stop in at PA on the way home... biggrin.gif

Got that set at Canadian Tire a few years ago the set was on special at 1/2 price ($15.00 or so )so i bought 3 sets like this always useful .

post #2894 of 7298

Music post

 

If you like sophisticated nature sounds and are willing to pay for them, check this out:

 

http://www.naturespace.com/

 

The page is also interesting because it explains theories of sound space, psycho acoustics and holographic sound.

post #2895 of 7298
Quote:
Originally Posted by MIKELAP View Post
 

Got that set at Canadian Tire a few years ago the set was on special at 1/2 price ($15.00 or so )so i bought 3 sets like this always useful .

Thanks!

Will be seeking me out one of those or similar when on sale, I picked up the Mastercraft 500 piece set in the wooden box quite a while back for $19.99, now that I think of it there might be one in there... Oh well still need to stop at Princess Auto (Harbour Freight for you US peeps) on the way home to see just what is there in dremel bits.

:beerchug:

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