specifics for copper manifold in mash tun

ok, two questions...

should the slots in the manifold face up or down? a german book i have states that they should face up in order to achieve a faster clear flowing result. also, that facing the slots down can lead to channel forming. the english book i have says they should face down, but without any reasoning.

second, (i may be going overboard on this one) can i maximize efficiency by varying the space between the actual slots in the manifold? what i thought was, that the flow nearer the drain of the manifold over a period of time would actually be more, thus depleating the mash in these areas faster of their solubles (assuming equal slot spacing). the areas further from the drain would then not be as thoroughly sparged. i thought i could offset this effect by spacing the slots further apart nearer the drain, limiting the intake in these areas. right now i have plans to cut at 10mm centers near the drain, graduating to 5mm centers at the furthest points from the drain.

anyone out there have further experience with such brainfarts?

Yes, you are overthinking... :cross:

I have my slots facing down. My thought was that I may have a stuck sparge if they faced up if the grain bed got impacted.

I think you are making this a bit more complicated than it really is.

Intuitively, the slots should point down. That's how I do mine. I don't think channeling will be affected either way, it's just that I think you have a bigger chance of clogging with the slots pointing up. That doesn't mean your manifold will clog if you do it that way, it means your odds are better with them pointing down. That is what I would recommend.

Regarding spacing, closer is better. Put in as many slots as you possibly can regardless of whether they are close to the outlet or not. I think you are fishing at the third decimal place trying to optimize this. Just put lots of slots in. I think the number of slots is more important than how they are spaced.

In the end, don't get hung up on efficiency. Raw efficiency numbers are very misleading and often pointless. There are a lot of variables that go into it and in the end, THE most important thing is consistent efficiency. I'll take a consistent 70% over a varying 75 - 90% any day of the week.

Prosit!