Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: kagliostro on May 13, 2024, 08:51:42 am

Title: Does someone knows if is possible to find this kind of flat spring ?
Post by: kagliostro on May 13, 2024, 08:51:42 am
Hi friends

Does someone knows if is possible to find this kind of flat iron spring

Measures are 0.1mm thikness, 6.2mm x 13.8mm and the "small moustaches"  get up 4mm from the base

Obviously we are looking for something that cutted can cover the required dimensions
(https://i.imgur.com/sDrT9Z7.jpeg)

they are used on this GU-50 Dissipated Sockets to transmit the heat from the tube to the dissipator and to compensate thermal expansions

(https://i.imgur.com/yk8HzOV.jpeg)

(https://i.imgur.com/PY2tjmE.jpeg)

As this kind of Dissipated Socket is not disposable new and very difficult to obtain used a friend want to try to modify aluminium cilinder dissipators that can be find on the web but he needs the Flat Springs

Thanks

Franco

Title: Re: Does someone knows if is possible to find this kind of flat spring ?
Post by: sluckey on May 13, 2024, 10:40:41 am
Maybe you could remove the inside layer of an IERC tube socket. Probably have to cut the outer solid shield off with tin snips.
Title: Re: Does someone knows if is possible to find this kind of flat spring ?
Post by: j-b-c on May 13, 2024, 01:22:01 pm
I'd use something modern that can be cut to shape.

https://www.fischerelektronik.de/web_fischer/en_GB/heatsinks/E01/Thermal%20interface%20material/index.xhtml

Title: Re: Does someone knows if is possible to find this kind of flat spring ?
Post by: kagliostro on May 13, 2024, 04:07:18 pm
Thanks friends

@ Sluckey

Ciao Steve

I think I've that kind of dissipated shield for Noval tubes

but easily the spring inside will be small, not enough tall and large for a GU-50 tube

@ j-b-c

I've find a dissipation foam pad on the web but it is rated only for 200° and those tube are hot like hell

Franco


Title: Re: Does someone knows if is possible to find this kind of flat spring ?
Post by: j-b-c on May 13, 2024, 05:21:17 pm
Fischer has a selection of silicon elastomers that are good to 250C.  Good enough to withstand molten solder.

Their carbon material goes up to 500C.

It would be ironic if the dissipator ran the tube hotter than naked.  Quartz is quite transparent to radiated heat, but that contact spring is working by convection and blocking much of the radiation that would otherwise pass through the quartz window.

https://www.pgo-online.com/intl/curves/quartz-glass-transmission.html 

edit: the 250C elastomers are here ==> https://www.fischerelektronik.de/web_fischer/en_GB/heatsinks/E01.01.000/Thermally%20conductive%20foil%20made%20of%20siliconelastomer/$catalogue/fischerData/PG/WFK25/search.xhtml
Title: Re: Does someone knows if is possible to find this kind of flat spring ?
Post by: sluckey on May 13, 2024, 06:43:58 pm
but easily the spring inside will be small, not enough tall and large for a GU-50 tube
But you said, "Measures are 0.1mm thikness, 6.2mm x 13.8mm". That converts to .25" x .5" to me. Very tiny!  Maybe you posted the wrong dimensions?
Title: Re: Does someone knows if is possible to find this kind of flat spring ?
Post by: Beezerboy on May 13, 2024, 09:53:44 pm
kina hard to tell the shape but they look like a "U" or a "V".    if so I would just cut a strip of aluminum about 6mm wide and bend up little "V"s, cut to length. unless the alu is dead soft it will have some spring back. might take some practice to get good ones but it shouldn't be that hard. alu is a much better conductor of heat than steel
Title: Re: Does someone knows if is possible to find this kind of flat spring ?
Post by: kagliostro on May 14, 2024, 10:57:33 am
@ j-b-c

Thanks for the info, very interesting the link

the only thing I can say is that tubes become Hot, very very HOT

@ Sluckey

Me Stupid  :BangHead: :BangHead: :BangHead:

Measures are 0.1mm thikness, 6.2cm x 13.8cm (or 62mm x 138mm) and the "small moustaches"  get up 4mm from the base

 :worthy1: :worthy1: :worthy1:

@ Beezerboy

the shape of the little moustaches is near a U, but on the lifted side the moustaches are shaped to better touch the tube glass, near impossible to be done by DIY

---

At the moment I'm valutating two materials

https://www.ebay.co.uk/itm/266494964239 (https://www.ebay.co.uk/itm/266494964239)

(https://i.imgur.com/M76yqzZ.jpeg)

and

https://kemtron-emc.com/it/emc/stock-di-bastoncini-in-rame-al-berillio/ (https://kemtron-emc.com/it/emc/stock-di-bastoncini-in-rame-al-berillio/)

(https://i.imgur.com/0C9lVPh.png)

Franco