[G600]

I have to advise you even if you have spare time, it's on the tricky side and can be painful...
I planned to recable the audio path, but no time left and quite fed-up...
I don't think I'll do that soon.

 

[ozaudios]

Hi G600, thanks for thephotos and info. You said 'I'm now looking for a perforated metal plate I can mount to close the amp, and mount some fan on it (with external PSU).'
 
I found old computer cases are good for metal sheet for odd jobs, most have holes for air-flow already there..... look for a local junk yard or recycling centre to get a suitable piece of sheet with holes, just trim to fit the amp. I also have an external power supply for the fan, it keeps the electrical noise out of the amp, a good idea.

 

[ozaudios]

I was thinking that a point to point soldered amplifier would be fun to build, then I looked at one, and the word 'fun' does not apply to it.

 

[G600]

Maybe not so fun, but quite a pleasure !
 
Thanks for the idea of old PC plates.
Actually I've found 5 minutes ago someone who can produce me a nice plate 100 % tailored on my measurements, and for just a few bucks.
I'm going that way !

 

[DefQon]

Just don't use the bottom plate anymore. Discard it and align the capacitors straight down and make sure leads are heatshrinked as they are carrying B+ voltage. Install cones on the corners of the chassis and you're done. Same concept that the Bottlehead Crack (and other amp's) employ. More airflow due to the rised distance from the bottom.

 

[G600]

Yes but this way I can't put a fan...

 

[DefQon]

  Yes but this way I can't put a fan...

 
Don't need a fan.

 

[G600]

I'll think about that.
The amp is working without a bottom plate or fan for 2 days (raised by some paper on corners), and after 90 min it starts to be very hot, a lot more than with the 2 80mm from Zenpunk.

 

[DefQon]

  I'll think about that.
The amp is working without a bottom plate or fan for 2 days (raised by some paper on corners), and after 90 min it starts to be very hot, a lot more than with the 2 80mm from Zenpunk.

How hot is hot?

 

[G600]

Nothing precise, but the top plate can't be touched more than 5 seconds, and the side plates start to get warm.
Nothing scary but unusual here. Maybe some gentle air flow will save component's lifetime and save me some cold sweat
 
I'm thinking of a totally custom made plate based on this, with 35mm feet and a 140mm fan mounted outside of the amp, and powered by an external wall wart...

 

[DefQon]

  Nothing precise, but the top plate can't be touched more than 5 seconds, and the side plates start to get warm.
Nothing scary but unusual here. Maybe some gentle air flow will save component's lifetime and save me some cold sweat
 
I'm thinking of a totally custom made plate based on this, with 35mm feet and a 140mm fan mounted outside of the amp, and powered by an external wall wart...

 
That doesn't sound right even without fans. Could be a short or bad solder. Most important thing of all are you taking measurements of the voltages? You should.

 

[G600]

Which voltages should I measure ?
I'll also measure the temperature this afternoon.

 

[zenpunk]

Just get some Tung-sol 5998 (expensive but fantastic sonic upgrade) and the LD will  run a lot cooler - just about warm without fans.

 

[Maxvla]

MKVI gets pretty toasty with no fans on. I wouldn't say his temps are unusual. My fans died after several months and I used it for a few days while new ones were coming and I was worried something was going to melt.

 

[Androb]

Just get some Tung-sol 5998 (expensive but fantastic sonic upgrade) and the LD will  run a lot cooler - just about warm without fans.

This! Before I upgraded the tubes mine got so hot aswell, maybe not burning myself, but really really hot. With different tubes the chassi is really cold instead.