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EL84 Class AB stereo amplifier chassis

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Jwillis:
I was considering that the metal work shop would do most of the bending and punching since they have the tools for it .Basic sketch below.
I was going with a brushed metal look with stained hardwood sides .Also considering polished .Gold chromate looks cool too but Anodizing I can't get done locally .
The cost quote is quite reasonable so I may even consider having 2 or 3 different metals finishes made . I wanted a keep a metal look to contrast with the hardwood .The positioning of the transformers were going to be right angles anyway taking into consideration the magnetic fields. Besides it just  looks better that way. But I'll might add covers but not sure. Theirs a total of 10 tubes  4 EL84 output pentodes, 2 kenotrons ,2 6N1P input drivers (also have 6N23P, probably go with this one ) ,2 6E1P indicators. All tubes are new old stock.I have the data sheets but they're in Russian . Small set back since I managed to sort of translate most parts of them.
Controls in front , inputs / outputs and power socket on the back.
 Thanks everyone for your valuable input .Cheers.

floobydust:
The Hammond 1441 steel chassis approach is full bends with spot-welds and complex woodwork. The aluminium 1444 chassis can't handle heavy weight though and I've had the spot welds break.

It helps to take a sheet of paper and some paper/cardboard cutouts or cutout photocopies of the bigger parts, to do a layout and see if there is enough room.
If you're using turret strips, sometimes they'll end up in a tight spot or you need an extra one. Coupling capacitors to EL34's might be large size and can take up more room than expected.
I think important is cooling, so the O/P tubes are not too close together 1" spacing seems small. The input and phase-inverter's need metal shields especially if using a tube rectifier. Several hundred volts swing near them and they will pick that up on the plates.

The worst part with a power transformer in the middle, is where the RCA jacks are. With both on one corner, one channel will need a long shielded cable run so the extra capacitance can unbalance the two channels and add something to fix that.
Stainless steel is hard to work with.

Jwillis:
 I did look at those Hammond chassis so thanks for informing me about the weight limitations. I chose Stainless because of its rigidity. Also I can get 4 different finishes at this local shop. #8 mirror , #4 brushed , #2 brushed  , and #2B bright .Others I have to special order at a much higher cost. Other metals include aluminum ,brass and copper. Un-coated aluminum starts to looks crappy after a while . The samples of punching they have  show no distortion and are clean . They said they can also recommend the best gauge for the weight . The transformers are the Hammond 1650E output at 3.5 lbs each  and the Hammond  370KX power at 8.5 lbs That's 15.5 lbs .So I'm get the professionals to do the metal work.I'm also considering  polymide sheeting on the inside.
I forgot about the caps. Thanks floobydust

floobydust:
You could do steel and get chrome plating, ala Dynaco. If you have to drill one hole or file something out, then you realize total agony with SS being so hard.
If they'll do all the CNC punching, then I'd lay out the entire chassis, including IEC power entry, output binding posts, RCA jacks, holes under the transformers for leads etc. Don't forget bias/balance pots and a #47 lamp ;)
Front Panel Express software is free, I did not check the library of parts, output is DXF. It might be useful.

Build the whole amp (layout) with paper and cardboard, I know a few people doing it that way and they enjoy that method.

Jwillis:
I've worked with stainless before . Sheet SS 304  is nothing compared to hardened stainless 630.
Small holes up to a 1/2 inch won't be problem . I have air die grinders and drills and tungsten carbide and diamond  drills and grinder bits from my HD mechanic days.Once I have a template made the metal shop will do the rest.

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