Experiencing problems to insert tubes

[talaerts]

Hi all,

I am building the 24V variant of the Aikido tube pre-amp, and the main pcb is ready. It's the PCB for 9 pin tubes. Just for fun, I tried to insert a 6GM8 tube (made in USSR) in one of the sockets.
Well, actually this seems to be very difficult. There is a lot of resistance, as if the pins of the tube are a bit too thick. I don't dare to use force, being afraid that I would break the tube.
What approach do you suggest?

regards, Tom

[kevinkr]

Solder flow down into the socket while you were soldering it? I have done this with the results you describe.

If you have a few spare sockets of the same type try inserting the tube into one of these sockets, that will tell you whether or not there is a problem. Should there be a problem with unsoldered sockets you might want to replace them with another brand/type.

[tubelab.com]

I have found that tube insertion is often difficult the first time on some of the current crop of Chinese white ceramic 9 pin PC board sockets. I usually use a junk tube for the first insertion. I have also used a little WD40 on the pins of the junk tube. Too much will make a mess.

[talaerts]

Originally posted by kevinkr
Solder flow down into the socket while you were soldering it? I have done this with the results you describe.

If you have a few spare sockets of the same type try inserting the tube into one of these sockets, that will tell you whether or not there is a problem. Should there be a problem with unsoldered sockets you might want to replace them with another brand/type.

I don't have spare sockets (it's my first tube project after all!). I will check about the solder. I don't think it happened.
I will also try contact spray which should act like a lubricant.

I wondered originally if it could be that the russian tubes are simply outside spec?

Tom

[kevinkr]

Haven't used the latest generation of chinese made pcb tube sockets so George may be right on the money on that one.

I haven't noticed any problem with Russian tube pins being unusually large. I have noticed that with JJ types recently, by comparison they are much skinnier than nos and other vendor current production.

[rdf]

Originally posted by tubelab.com
I have found that tube insertion is often difficult the first time on some of the current crop of Chinese white ceramic 9 pin PC board sockets.

And for some a long time after as well. Something about the tube-side sleeve profile and perhaps the way the sleeve fits in the substrate makes tube insertion permanently difficult with some new Japanese ceramic sockets compared to any of the bakelite NOS sockets I have.

[Brian Beck]

Originally posted by tubelab.com
I have also used a little WD40 on the pins of the junk tube. Too much will make a mess.

Yep, or a little Caig DeOxit.