Case has been glued, router trimmed, sanded, stained and 4 or 5 coats of lacquer so far, now let it dry properly and sand it flat before last coats.
The final bits from china just arrived, I will be ready for a test run within days, just have to crack on. Next, build supports for heatsinks and fans then start on the electronics.

That's coming along nicely.

Yip,very interesting. Can't wait to hear how it turns out.

Great stuff.

I sit back in awe

Thanks Martin, something different, comes with its challenges.

Now for today's list of progress and cockups.

It all begins late last night, things are as they should be, a quiet and peaceful dusk enjoyed with a glass of scotch and a soldering iron.




After some learnings, such as WHY you use hooks to measure the current on the resistor, things seemed to progress.



After that scare, the baby still seems to be alive, sturdy stuff good Sir Wonfor. 
Adjusted the current to 175mV, those are some sensitive pots, a hairs step gives you 50-100mV. DC offset to 12mV at speaker terminals, the chews thread said 10mV, couldn't get it, I hope 12mV is close enough
.
The flop sweats started to fade, perhaps there is hope after all. 

The heatsinks seem to be up to the job, barely felt any heat buildup. The fastening bars on the FETs got to 55-60C, probably close to the package temps.
I am wondering, the heatsink chart, does it refer to package or heatsink temp? Is this setup having too low a heat transfer to heatsink?

A joyous occasion, the beast is ready to bellow its first roar, but alas, something is rotten in the state of denmark.





I hooked up the amp to the desk speakers, my workhorses through the decades, JPW-510s.
Before I started feeding signal into the amp the main house fuse popped.
Well, I tried once more, now I had sound on the right side only, the left, cold as ice, dead in the water, damn. Time once more to sweat profusely, is this the end, will it ever live a full life?

The hunt begins, the first thing i noticed, the amp board fuses were fried, not too surprising. 
I started beeping to see if there was a short. Yup, it seems the FETs feet had a direct short to ground, what the hell.

I release the FETs from the heatsink, the beep is gone. Look at this craziness, did i screw it too hard?



Maybe the pads just melted when they got hot, another learning. A straight bit of aluminium and FETs at an angle, not a good idea, uneven pressure. I wish I had my ceramic insulators, they are still in china post limbo.

No, this was not the answer either, after a while i discovered THIS.



The heatshrink had failed me, the heat softened it and the slight pressure from the alu bar caused a penetration, shorted straight to ground.
Perhaps I will lift the PCBs higher so the lead is not under the bars, lets see.

I will get some more fuses later tonight, I pray to the gods of magic blue electrin smoke all will be well.
More to come very soon.

Best of luck

I find the answer often comes to me if I go away from the problem for a while, sometimes the following day

A shorted output transistor is very likely. Can you isolate the channels, test each one separately? Before that, test all output devices for shorts. Then replace the fuses with, say, 10 ohm wirewound resistors which will give you a few seconds to see what's happening under quiescent conditions.

Have you used the insulators under the output transistors.

Greetings colin.

Here you are, they are some of these, www.ebay.co.uk/itm/111316754584?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT .

If it is of any help, I compared ohms between the 2 amps, output transistors legs G to S about 3 ohm on the problem side, Mohms on the other, same on both output transistors. They measure the same out of the circuit.