As some of you know, this is what the original device looks like.
Original, unmodified setup
Now, I've made an extension for it, that will sit between the lid of the boiler and the condenser head.
The extension looks
It's centre section is of 22mm copper pipe - which I have filled with copper mesh for reflux packing.
The top of it looks
As you can see, it's just the 22 mm centre section, that has a 22mm sleeve connector that's been soldered on and to a 22 to 15 mm reducer, which in turn has been soldered onto a short length of 15 mm pipe and that has been terminated with a 15 mm compression connector.
You may think that's a bit small, but the connector seems to be the same size and thread as the bottom of the reflux condenser - the only possible modification that might require is to make something to act as a washer - those of you who have one of these stills will know that the nut that connects the condenser to the boiler lid is a flanged nut, that has a piece of stainless pipe sweated into place inside the threaded/flanged section. Ergo, 15 mm is the ideal adaptor size.......... luckily!
The bottom of the extension
That's basically the opposite of the top i.e. 22 mm pipe into 22 mm sleeve connector (those who have read up will see that it's a "solder ring" model - to ensure a bit of safety and common sense, it was heated up and the solder in the ring shaken out so I could ensure that the solder used was lead free) into a 22 to 15 mm reducer, followed by a short length of 15mm pipe which is terminated with a flanged boiler connection, which, also luckily/coincidentally, is the same size as the hole in the lid.
It's a pretty basic construction. The only thing I had to do first, before any soldering etc was to cut the pipe to length and then take the end of the copper mesh, roll it up, tie it with string and pull it through the 22 mm centre section gently, making sure that as the mesh was pulled through, it was rolled correctly so it expands slightly in the pipe and holds itself in place (no need to make up any blanking washers etc to keep it where it is - it's self supporting), then the sleeve's, reducers and short pieces of 15mm cut and prepared. The olives and compression connectors joined onto the 15 mm pipe, but then the actual connectores removed so only the olives and cap nuts remained in place.
I did get a couple of silver solder rods, but my blow torch, only being a cheapo butane/propane mix model would melt the rod but wouldn't get the copper hot enough to run (and the flux paste might have had something to do with that as well - I'll be investigating that more another time). So I had to revert to lead free plumbers solder, which should be Ok, it's designed to work with water, and as the boiler will only ever hit about 100 degrees C, shouldn't be a problem.
Now, what's the point of this ? Well, as the still is a "coolant management" model, it can be a bit of a bugger to keep the reflux head cooled to the correct temperature. With the water flow set to about the rate suggested in the paperwork, it will only run stable at about 82 degrees C, which is a little too warm (boiling point being 78.15 C if I remember correctly). So the extension removes the condenser to 1 metre above the boiler, hopefully creating extra reflux space (or that's the idea) and reduces the heat that transfer's from the boiler to the condenser through heat induction through the metal. So, in theory, it should also help to keep the water flow keeping the reflux head at the right temperature - plus a bit of work on the cooling pipe connections should allow me to increase the water flow to the condenser as well.
All things being equal, I hope to give it a trial run over the next week or so....
Oh, and I'll be replacing the "ceramic saddles" in the condenser head with "proper" raschig rings.
I'll post how I get on.....
