Installing new B7G valve base

[Luxman1050]

Hi all
just quickly any ideas on types of rivets and tools required to put in new or NOS valve bases.
I tried my rivet gun and it looks awful. Plus difficult to get the stud to line up as the surround on base gets in the way. I've had good look round and just come up with craft studs.
Pics attached blo.... awful.

[joebog1]

Origional rivets can be obtained from a boot maker. They are really cheap. Finding a boot maker ?? Thats your problem. Rivetting tool ( a tiny anvil and punch) is also available from there.
I use 3 mm button head allen screws in stainless steel!! Very easily obtainable, cost a few cents each and last forever. I use 3mm X 6mm ISO if thats any help. 6mm allows for a ITL ( internal tooth lockwasher) if required.

Joe

[paulsherwin]

I just use nuts and bolts. That's what a repairman would have done back in the day.

['LIVEWIRE?']

Likewise, Paul. Nuts and bolts for me.

[Luxman1050]

Thanks guys I'll have a browse later.
Did think nuts and bolts but like to if I can obtain the original look.
Chris

[Alistair D]

Try this supplier.

http://doidge.com/original/english/semitub.html

Al

[snowman_al]

They are called 'eyelets' or 'hollow rivets'. You will need a rivet tool (punch and die) to close them. I expect there isn't enough space to use rivet pliers.
Look for leather work tools and eyelets.

[Luxman1050]

Cheers everyone I'm sure I'll get something with info provided.

[John10b]

Instead of replacing the valve base why not replace the individual sockets, I’ve done this a few times successfully and found it a lot less bother than drilling out the whole base.
John

[John10b]

I should have said that some of the new valve bases did not fit into the hole, thought you should know. Only trying to be helpful.
John

[Luxman1050]

I can see what you're saying John but how would you prise open the surround from under the chasis to get the holder out? Quite tight under there and they're only small. Plus closing up the gap afterwards to keep base in surround.

I've got plenty of donor bg7 bases I can use, don't need to buy new ones plus these are better quality than a lot of the new stuff, around personal opinion.
Cheers Chris

[ms660]

A B7G valve holder has seven individual sockets, each of those individual sockets can sometimes be replaced no problem....Usually de-solder, straighten up the tag and then push from underneath.

Lawrence.

Pedantic mode... Nuts and screws, bolts have an unthreaded bit near the head.

[ms660]

Originally Posted by merlinmaxwell

Pedantic mode... Nuts and screws, bolts have an unthreaded bit near the head.

Just like my box of coach screws...

Lawrence.

[John10b]

Chris perhaps I didn’t make my self clear. It’s as Lawrence explained, you can usually replace each valve pin socket, it can save you having to change the whole base, hope that makes it clear.
On one job I was doing I had a very intermittent fault, it turned out to be one of the sockets in the valve base being fractured, I managed to pull out the faulty socket and replace it.
John

[Luxman1050]

Yes I see what you mean I did wonder initially.
That's what happened funny enough V3 connected to V4 the pin connecting both had snapped as on desoldering with my plunger it came with it hence I think that's why V3 valve was glowing and that thud through the speaker also it was obviously shorting.
I did try that trick remove from another base but due to the bending snapped both which I tried. I'll give it another go but they seem quite fragile. Unless I'm just heavy handed.

[John10b]

I don’t think your heavy handed, I have found some of them to be quite fragile, others no so, don’t know why that is.
John

[G6Tanuki]

The 'fork' style connectors in those valve-bases are a constant source of problems - they're stamped from brass which goes brittle with age and cracks at the bottom of the fork, so there's no tension in the spring and contact gets lost.

"new old stock" valve-bases are likely to have the same underlying intrinsic brass-embrittlement problem.

I invariably replace them with more-modern bases - the type that have a white PTFE insulator and formed, not stamped, contacts. 6BA screws/nuts and a 'star-washer' under the nut being my preferred fixative. OK, you lose the 'original' appearance, but I prefer reliability/functionality over appearance and you generally don't look at a n amplifier or radio-chassis while you're actually using it.

[dave_n_t]

Originally Posted by cdm1christopher

Thanks guys I'll have a browse later.
Did think nuts and bolts but like to if I can obtain the original look.
Chris

Quite a few of my sets mix rivets and nuts and bolts (screws). I think it depends on the function of the valve - anything likely to be microphonic uses a nut and bolt with a rubber grommet.

Usually, that seems to mean the frequency changer, and the diode/triode detector; whereas the IF, output, and recs reem to be rivetted.


dave

[Luxman1050]

I invariably replace them with more-modern bases - the type that have a white PTFE insulator and formed, not stamped, contacts. /QUOTE]
Not seen those advertised anywhere PTFE insulator formed contacts.
Have you got a link?
Cheers Chris