Mounting tubes in a case

[suncrush]

I'm planning to make a double-barrelled valvecaster to replace the first unit I made.  I did the original with the tube mount screwed to the case, so the tube comes out through a hole drilled in the enclosure.  I'd like to build this unit with the tube fully enclosed so that I can mount it to my pedalboard and move it around.

So, two questions.

1. What have y'all used to mount tubes horizontally inside the case and secure them.

2. Is it necessary to cut vents in the enclosure, or are 12AU7's not hot enough to worry about it?

[rutabaga bob]

I have just cut and bent a bracket out of scrap metal.  One side large enough to mount the socket, the other wide enough to put mounting holes in.  All that's left is to bolt the bracket to the enclosure.

I would think ventilation couldn't hurt.

[digi2t]

I would think ventilation couldn't hurt.

One option...



I would definitely ventilate in some manner.

You can find PCB with mounting holes incorporated, and use that to mount your socket.

[rutabaga bob]

Dino...if he uses the pcb, he'll still have to mount that to something else inside the enclosure.

I like the first pic...have seen something similar in the past.

Cheers!
Larry
Here's a pic of what I've used, for what it's worth...

[vigilante397]

I think the idea with the PCB is that it's easy enough to mount the PCB to the enclosure via standoffs.

[rutabaga bob]

My thought then is: why couldn't you just mount the socket with standoffs?

[digi2t]

Yeah, you're right Larry. My mind was going in the direction of mounting the PCB in the bottom, and the tube on the side, sort of something like this;



Makes for a bigger enclosure, I know. I guess that's why most mount the tube(s) on the outside, so as not to sacrifice so much pedalboard real estate. Also automatically takes care of the cooling issue.

[rutabaga bob]

There y'go - problem solved!  Nice, Dino!

[Renegadrian]

Tubes at 12V don't generate heat enough to consider ventilation...do it only at hi voltage (it's rock and roll!)

[davent]

I think it was Paul Marossy who made a bracket with a mounted tube socket, the bracket was attached diagonally in a corner, saves a bit of space.

I've mounted lots of tubes horizontally using 'L' brackets to hold the material (aluminum sheet, pcb, garolite) the sockets were mounted to.

dave

[amptramp]

Tuning eye tubes always had to be mounted so they could be seen.  This Marconi 252FM uses a clamp mounted to a bracket with a slot so the tube could be moved up front to the cutout in the dial:



My Fisher KM-60 tuner has a 9-pin tuning eye that has a spring-loaded mounting with the vertical bracket held onto the chassis by two springs.  This facilitates removal and replacement.  The tube in on the upper right in this picture:



All kinds of hardware is available for tube mounting.

[greaser_au]

Tubes at 12V don't generate heat enough to consider ventilation...do it only at hi voltage (it's rock and roll!)

for a 12A*7, the heater on it's own wastes almost 2 watts - over time it will get quite warm  in a closed box      

david

[Renegadrian]

Tubes at 12V don't generate heat enough to consider ventilation...do it only at hi voltage (it's rock and roll!)

for a 12A*7, the heater on it's own wastes almost 2 watts - over time it will get quite warm  in a closed box      

david

2 watts on which voltage?! Of all the valvies I made only one had an internal tube, and there was just a little heat, the tube gets slightly warm at so low voltage...

[bluebunny]

Even if the plate is low voltage, the heater is still going to be 12V or 6V.

[suncrush]

Tubes at 12V don't generate heat enough to consider ventilation...do it only at hi voltage (it's rock and roll!)

for a 12A*7, the heater on it's own wastes almost 2 watts - over time it will get quite warm  in a closed box      

david

2 watts on which voltage?! Of all the valvies I made only one had an internal tube, and there was just a little heat, the tube gets slightly warm at so low voltage...

Yes, and I plan to use 2, if the breadboarding works out.  I plan to run it at 24V, and if that's enough to get a 12AY7 to sound good, I plan to build it switchable between the U and Y.

[Groovenut]

Tubes at 12V don't generate heat enough to consider ventilation...do it only at hi voltage (it's rock and roll!)

for a 12A*7, the heater on it's own wastes almost 2 watts - over time it will get quite warm  in a closed box      

david

Yes, and I plan to use 2, if the breadboarding works out.  I plan to run it at 24V, and if that's enough to get a 12AY7 to sound good, I plan to build it switchable between the U and Y.

2 watts on which voltage?! Of all the valvies I made only one had an internal tube, and there was just a little heat, the tube gets slightly warm at so low voltage...

P=V*I or 150mA heater current at 12 heater voltage = 1.8 watts (300mA @ 6V = 1.8W) Regardless of plate voltage you'll be emitting some heat

[digi2t]

Getting geared up for a new project, I found these on Ebay...



Brackets, socket, and four sets of mounting screws/nuts, for $4, shipping included. Picked some up. Can't justify wasting my time at that price.

http://www.ebay.ca/itm/201525599338?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[suncrush]

Yeah, you're right Larry. My mind was going in the direction of mounting the PCB in the bottom, and the tube on the side, sort of something like this;



Makes for a bigger enclosure, I know. I guess that's why most mount the tube(s) on the outside, so as not to sacrifice so much pedalboard real estate. Also automatically takes care of the cooling issue.

What are those posts called?  I can't find them to order them.

[rutabaga bob]

Standoffs, or threaded standoffs.

[suncrush]

Standoffs, or threaded standoffs.

Gracias.  Not available at Tayda or Mammoth.