Correct Size Knock Out Hole Punches

[ZeusMC]

Hi all,
What would be the correct size for a  12AX7  B9A tube socket, a K8A  6V6 octal socket and  if different what might be required for rectifier sockets?
Thanks.

[K O'Connor]

Hi Guys

The chassis hole diameter required by tube sockets varies with the socket size and whether the socket is mounted inside the chassis or outside of it, as some sockets are stepped while others have a constant diameter cylinder. You should take some measurements from the sockets you have, r from drawings ff those you intend to use.

Have fun

[makinrose]

Kevin is correct that they vary so I basically figured out which sockets I like and purchased knock out punches accordingly. For noval sockets the most common size is 3/4" but there are others. For the octal sockets 1", 1 1/16", and 1 1/8" are all fairly common.

[ZeusMC]

Hi Guys

The chassis hole diameter required by tube sockets varies with the socket size and whether the socket is mounted inside the chassis or outside of it, as some sockets are stepped while others have a constant diameter cylinder. You should take some measurements from the sockets you have,  from drawings ff those you intend to use.

Have fun

" mounted inside the chassis or outside of it " Yes I realised that, after a bit more research a little while from when  I made my original post. I asked as intending to buy Chinese even though have to wait a week or so for them to turn up, have bakelite sockets and metal frames. Ebay UK item number 203593328614   and 321001703678 it gives the sizes of sockets. I've not decided whether to fit them inside or outside of the chassis. Is the difference only cosmetic or is there a reason to fit them, one or other way?

Still a bit confused about tube socket sizes. If someone could look at the listing drawings showing the socket dimensions. And advise what would be the correct knock out hole size punch to get...... would be much appreciated

Kevin I bought the Antex 660A temperature controlled analogue soldering station, about 2/3rds price of the Weller. Antex are an old long establshed UK company who make the irons in the UK. The station is made under license in China, before Covid kicked in, they visited the factory quite often. So top quality of unit is assured. I also bought a UK made solder, 26SWG 250g ROSIN FREE SOLDER, 63/37  item 263701641500

Cheers

[ZeusMC]

Kevin is correct that they vary so I basically figured out which sockets I like and purchased knock out punches accordingly.  For noval sockets the most common size is 3/4" but there are others.  For the octal sockets 1", 1 1/16", and 1 1/8" are all fairly common.

OK thanks for replying.

[K O'Connor]

Hi Guys

Re: tube socket drawings:
Some sockets have a stamped metal bracket that makes the mounting orientation obvious, then there is only one dimension that you need to match with the socket. Make sure the socket is not so loose in the large hole that the bolt holes fall onto the circumference, or worse, into the hole itself.

Sockets that have a bracket that allows top or bottom mourning may have one or two dimensions to note, but most often it is a single dimension.

When there is an option for top/bottom it is mostly aesthetic which you choose. The tube insertion force is borne by the bolt and nut or by the chassis, with the extraction force borne in symmetric fashion.Sockets with tube shields are typically top-mount. Bottom-mount's only advantage is in bulk removal of the circuitry and wiring to the socket, assuming everything must go. Otherwise, there is no inherent advantage to either top/bottom mounting.

Re: solder:
Why would you buy rosin-free solder? The rosin helps to clean the surfaces that are meant t accept the solder.

[ZeusMC]

Hi Guys

Re: tube socket drawings:
Some sockets have a stamped metal bracket that makes the mounting orientation obvious, then there is only one dimension that you need to match with the socket. Make sure the socket is not so loose in the large hole that the bolt holes fall onto the circumference, or worse, into the hole itself.

Sockets that have a bracket that allows top or bottom mourning may have one or two dimensions to note, but most often it is a single dimension.

When there is an option for top/bottom it is mostly aesthetic which you choose. The tube insertion force is borne by the bolt and nut or by the chassis, with the extraction force borne in symmetric fashion.Sockets with tube shields are typically top-mount. Bottom-mount's only advantage is in bulk removal of the circuitry and wiring to the socket, assuming everything must go. Otherwise, there is no inherent advantage to either top/bottom mounting.

Re: solder:
Why would you buy rosin-free solder? The rosin helps to clean the surfaces that are meant t accept the solder.

[ZeusMC]

This was available as a 250g roll, the Kester 245 was import to UK and only available in a 500g roll, lot more expensive. Other UK made 63/37 that are available, because of health and safety regulations, restrict the sale to professional business users and have to provide business documentation, that are a professional business user. I have a fume extractor for my stained glass, also little flux brushes, could I use one of those to apply flux to the solder join, if really necessary?
Did you see the data and spec on the listing for the solder I bought?
Thank you.

[makinrose]

You definitely want to have a rosen core solder. If there are regulations with lead-based solder you might consider using lead-free solder. It takes some time to get used to but it works well if you have a good solder station.

[ZeusMC]

You definitely want to have a rosen core solder.  If there are regulations with lead-based solder you might consider using lead-free solder.  It takes some time to get used to but it works well if you have a good solder station.

If I'm using new components, not repairing, scavanging old stuff for parts. As new component leads do I need to consider rosen core solder and oxides?
Cheers.

[K O'Connor]

Hi Guys

Nominally, shiny leads should accept solder well, but the lack of oxidation, etc visible to our eye does not mean the surface is perfect.

In my kits and amps I use a lot of resistors that I bought a long time ago or in large quantities. I use steel wool to clean them before installing them, and advise in the kit notes to do so for all non-shiny leads.

The problem with lead-free solder is that the solder does not flow and fill as smoothly as leaded solder does AND the cooled joint is not shiny. You cannot tell visually that it is "good". The same goes with silver solder, which to me is a complete waste of money.

The carbon footprint and related pollution of all kinds is much worse for lead-free solder than for leaded solder. There are specific minerals that must be added for lead-free solder to flow and to wet in any manner close to "real solder" - hehe. Lead is extremely bad for everyone and its limited use benefits everyone. However, for reliable solder joints you can't beat it.

You can brush on rosin with a little "acid" brush, just like in olden tymes. Rosin-core solder provides just the right amount for each connection and saves a step. Remember to let the joint cool and remove the dried rosin mechanically instead of chemically, as stated previously and elsewhere.

Have fun

[ZeusMC]

Hi Guys

Nominally, shiny leads should accept solder well, but the lack of oxidation, etc visible to our eye does not mean the surface is perfect.

In my kits and amps I use a lot of resistors that I bought a long time ago or in large quantities. I use steel wool to clean them before installing them, and advise in the kit notes to do so for all non-shiny leads.

The problem with lead-free solder is that the solder does not flow and fill as smoothly as leaded solder does AND the cooled joint is not shiny. You cannot tell visually that it is "good". The same goes with silver solder, which to me is a complete waste of money.

The carbon footprint and related pollution of all kinds is much worse for lead-free solder than for leaded solder. There are specific minerals that must be added for lead-free solder to flow and to wet in any manner close to "real solder" - hehe. Lead is extremely bad for everyone and its limited use benefits everyone. However, for reliable solder joints you can't beat it.

You can brush on rosin with a little "acid" brush, just like in olden tymes. Rosin-core solder provides just the right amount for each connection and saves a step. Remember to let the joint cool and remove the dried rosin mechanically instead of chemically, as stated previously and elsewhere.

Have fun

Cheers for the info, much obliged