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Bakelite top shelf, any good?

Hello,
my trusted carpenter "builder" made me an oak container with a bakelite cover telling me that for my purposes it could be the job.
I was wondering if it is possible to use this material instead of traditional metal / aluminum top shelf, after all it was used in old radios once without problems. My only doubt is the insufficient heat dissipation given the low conductubility, which could be partially obviated by making a certain number of holes at the top.
 

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Hello,
my trusted carpenter "builder" made me an oak container with a bakelite cover telling me that for my purposes it could be the job.
I was wondering if it is possible to use this material instead of traditional metal / aluminum top shelf, after all it was used in old radios once without problems. My only doubt is the insufficient heat dissipation given the low conductubility, which could be partially obviated by making a certain number of holes at the top.

Yes, the lack of heat dissipation for transformers is a drawback, depends on how hard you're running them. Also depends on how powerful a circuit you intend to build. A little single-ended stereo amp would probably be okay. Four big KT 120's might be a problem. No shielding, but for a power amp that shouldn't be a problem. But if there's a serious flameout underneath for any reason, that would likely ignite the whole top plate.

You could add a copper or aluminum sheet inderneath to reduce the chance of fire hazard.

I use 1/4" Delrin for top plates. No short-to-chassis issues, which I like, it's pretty heat-proof, and it's very inert which reduces microphonics. I've certainly seen some nice wood-crafted amps, but they're usually low-powered affairs and take safety factors into account.
 
I didn't know Delrin, I went to read about and it is said to be a mid-way between metal and plastic....in appareance it seems the PTFE but less expensive.

It would be for a SE medium-power amp, I especially fear with power tubes and the 150VA transformer for possible overheating or fire hazard...the add of an aluminium/copper plate underneath it is indeed a necessary option, and for high voltage safety (safety earth bond through a metal bolt).
 
Delrin is great. Very rigid but super easy to machine. I can drill a whole top plate with Forstner bits in about 10 minutes. ;-) I do ground the transformers and chokes to the main buss, though.

In your case a metal liner would work. But since you have the option to remove it, maybe a metal top plate would be better. It also looks as though that material (is it luan or thin ply? I can't tell...) doesn't cut very cleanly. Just my .02!
 
In the US Corian is a nice product too but its 1/2 inch thick so top mount sockets or if you bottom mount the sockets the tube sits in a little well. You can pick up Corian cutoff scraps from your local kitchen remodeling and cabinet shop for free or cheap. picking up kitchen sink hole cutout scrap givey you the whole top, then just square it up on the table saw. you can sand /saw corian too, it works just like wood.