I just finished building a head for my rusty old amp. I used a snakeskin vinyl to cover the box, glued it with some spray glue and used staples at the edges. The issue I am having, or rather, will be having soon, is that the heat from the power tubes and the rectifier tube will cause the glue to soften and the vinyl to soften. I plugged the amp in for about 45 min and felt that the area directly above the tubes was hotter than I would like it to be.
Has anyone had success with a passive heatsink approach? I'm thinking of putting a sheet of 1mm metal on the top of the chassis, directly above the power tubes and rectifier tube, bolted to the inside. Would this be largely a waste of time if the vinyl is sandwiched directly behind it? Maybe I should get some 1/4" spacers and offset the sheet a slight bit lower from the vinyl? My main concern is that the vinyl will melt or grow brittle after repeated uses of the amp.
The clearance between the top of the 5U4 rectifier tube and the inside top of the chassis is about 4.5".
Thanks
Built a new head, need heat dissipation plate
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Shottky
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CurtissRobin
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4.5" is a lot of clearance but if you're uncomfortable with the temperature of the covering and its glue then you need to do something. Are there any vent slots for air circulation or is the head cab a blind hole? I have a Traynor YBA-1A that's a 90 watt amp in a blind hole so the factory installed a small cooling fan on the chassis blowing across the power tubes. I know a lot of guys hate fans but it's worth considering if you don't want to cut vents in your head cab.
You can certainly put a sheet metal shield in there with airspace between the metal and the wood of the cab. As the metal warms up it'll both shield the wood from the heat and encourage air circulation by convection. If you do that be sure to mount it so the thing doesn't provide its own solos while you play.
KennyO
You can certainly put a sheet metal shield in there with airspace between the metal and the wood of the cab. As the metal warms up it'll both shield the wood from the heat and encourage air circulation by convection. If you do that be sure to mount it so the thing doesn't provide its own solos while you play.
KennyO
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Shottky
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It's open to the front and rear at the moment, aside from a 3-inch cutout for the control panels. I'm going to use some grill cloth to cover up the front though.
I was thinking about a heat-resistant tile of some sort while I was falling asleep last night, but if it's rigid it probably would be tough to drill. I think I'll have to peruse the local student shop and see if they have some scrap metal sheeting left over from student projects.
I was thinking about a heat-resistant tile of some sort while I was falling asleep last night, but if it's rigid it probably would be tough to drill. I think I'll have to peruse the local student shop and see if they have some scrap metal sheeting left over from student projects.
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