![Confused :econfused:](./images/smilies/icon_e_confused.gif)
This is the hardware that came from http://homedistiller.org/forum/viewtopi ... 15&t=48599 - a modification of a brilliant design by YHB. Thank you, sir.
Without rehashing the entire thread, this thing can do it all except CM. We have LM, VM, and pot still modes selectable by a clever slide valve. I modeled it using Rhino 3D to ensure everything would come together properly. In use, a stainless slide valve, closed on one end, can be positioned exactly in the vapor column to force the vapor into a big product condenser, my jumbo shotgun - http://homedistiller.org/forum/viewtopi ... 50&t=47406 - this makes it a pot still, zero reflux. With the valve at the other extreme, we have 100% reflux, and a LM head just above can (if installed) execute pure LM duties.
With the valve partway, it's VM. Reflux ratios can be varied through the entire theoretical range.
From the top, valve closed. The vapors must travel upwards to the LM head and/or reflux condenser. Valve 1/2 way open... vapors are being partially diverted into the 2" copper tube to the right, leading to a product condenser. The valve body is a tricky piece. It must contain a full 2" Cu pipe installed perpendicular, so I made it from a 2" coupler and 2 copper ferrules. This will leave a thin web of metal after it's bored open for a 2" cross-member.
Next came the slide valve, made from a short piece of 304 SS tube (2" OD) and a SS disk soldered into one end. This required a huge boring on one side, and the end cap was drilled and tapped for the adjustment screw, a 1/4" X 20 stainless threaded shaft.
The shaft is installed into a Pb-free brass compression fitting installed into the end of a normal 2" copper cap. Two viton o-rings keep the shaft secured and sealed inside the compression fitting. I had huge grief trying to make a shaft and valve that was straight and true. This thing slides inside a 2" copper with hardly any room to spare, and things tend to bind up badly when everything isn't lined up perfectly.
The other issue is that the valve must not be allowed to rotate. If it does, it can theoretically seal off the vapor path to the boiler, and that equals big boom... In this state, as pictured, it CAN rotate. Had to fix that, and that was the hardest thing to do properly to this point.