Thanks heaps for the info, Gary

I'll use those dims to build my pipes with then.

The 96mm diameter is perfect - the only 316 0.010" stainless I can get at a reasonable price is 305mm wide (by 1m long), so 96mm will need 301.4 of sheet. Which leaves 3-4mm overlap to spot-weld on.

I'd be more comfortable if the sheet was 310mm wide - just to give me a bit more room to move in, but I might just be able to squeeze it using the 305mm stuff.

There is one other place that I can get 316 0.010 stainless from, and it's 600mm wide - but they have a AU$60 cutting fee on top of the sheet price, which brings it closer to 200 bucks a sheet. And I'd end up with about 290mm left over that would be next to useless.

Do you have any suggestions on how to make the bellmouth on the tailpipe at the Turbine end? They look like about a 1cm flange affair...

Oh, one more question: What distance do you space the start of the tailpipe from the tip of the Turbine's exhaust cone? From a lot of pics I've seen, it looks to be around 15-20mm.

Thanks again for your help on this - much appreciated...

BJ