by db1979 » Wed Feb 07, 2018 9:59 pm
G'day all,
As the title suggests, I'm considering building an inline gin head.
I've got a limited amount of 4" copper left over from my 4" bubbler build so I'm looking at using what I've got to my best advantage. In saying this, I would also like the gin head to be able to double as a packed section.
So the idea is to have a 4" section a bit over 500 mm long, easy flanges on both ends with a sieve plate (1.6 mm holes on 5mm grid) at the bottom end (interchangeable as detailed below), a 2" sight glass to monitor the oil bath at the bottom and a SS ball valve just above the sieve plate to drain off oil. There will be no downcomer. It will have a 2" blockhead take-off for the PC to be attached by easy flange at the top. The top will have a 4" cap to be able to easily change botanicals after putting the RC back to full reflux.
When used as a packet section I would run it under the RC, but it will be above the RC when run as the gin head. I'd use a different sieve plate for the packed section (interchangeable), 3mm holes or possibly 5mm holes. Thoughts anyone? Obviously the SS ball valve would remain closed when used as a packed section, and the sight glass would be useless. I'd prefer to use scoria for packing based on what others have said but I'd probably go with SS scrubbers till above the sight glass then use scoria for the rest. This would help look after the sight glass from being damaged when filling with scoria.
I'm wondering if a sieve plate will function well enough for the gin head with a SS ball valve tap attached to the side to drain oils. The ball valve would be positioned just above the sieve plate. Wondering if I could use a cloth bag for the botanicals. I don't have enough 4" to make a basket out of copper. Maybe I could get my hands on some SS perforated sheet instead? I'd also like to make a mash tun one day so any leftover might come in handy for that too as a false bottom. Midway metals do a 304 and a 316 grade perforated sheet at 0.7mm thick, 1.6mm holes at 2.54mm centres and 36% open area. Sheet size is 8' by 4', so far more than I'd need.
Two main reasons for going with a sieve plate option are to increase the volume of the packed section so I can make best use of my copper and I figure it will be heaps easier to build than with a large bubble cap and riser.
When running the gin head I'd only use neutral in the boiler with the RC directly above the boiler, followed by the gin head then the PC.
One potential issue I can see is that the oils would need to be drained every time the RC is put into full reflux otherwise it would defeat the purpose of having a drain valve... Being a sieve plate the bath would just fall through and the oils would enter my boiler. I wonder if it's usual practice to start a new batch of botanicals off without an oil bath anyway? In other words: drain oil bath, full reflux, change botanicals, shut off RC.
At the moment, I'm not calling this a Carter head because it's not offset... Have I got that right? I'd like it to function just like a Carter head though.
I'll add a diagram of what I'm thinking later if what I've written so far doesn't make any sense. Geez I hope it makes sense after writing all this! Thanks for reading :greetings-waveyellow: