Blockhead vs 180 degree over the top

[Donny]

Hi all
I'm in the middle of building a 4 "plated column , modula 4 trays to start , 2 inch bubble caps 75 mm x19 mm downcomer 23 mm depth 1" caps
RC 4"x150 mm 5 X1 inch
PC.2 1/2"x7x1/2"x 700 mm plus a packed section that I haven't made yet everything else is complete accept I haven't got the 3" glass peepers yet or haven't decided which way to go i.e. Blockhead or 180 over the top
I've got a couple of questions that I hope someone can shed some light on ..
first
Can anyone tell me what the advantages / dis advantages of a blockhead vs 180 degree bend over the top into PC. is it only for height restriction ..
second .
My boiler is a keg with a 2" Ferrell do I need to change this to 4 " i.e. Will the 2" cause restriction
Third
if I go blockhead is it better to come out of main column with 4 " or is 3" ok
Think that's about all for now .. thanks in advance and if anyone has any tips /suggestions positive or negative don't be scared to pipe up

[scythe]

Advantage of blockhead is the reduction in overall height.
Disadvantage (if there is one) would be possible extra cost in fittings and reducers.

2" will not cause any noticable restrictions as the vapour speeds up through the 2" but once it gets to the 4" diameter it all slows back down again.

For the branch off the blockhead its best to use whatever you can get your hands on for the price you want to pay.
If you jave a 2.5" PC you could use more of that if you have left overs.
2" would be your cheapest option especially when making it modular, fittings and triclamps add up quickly.

Whatever size you choose will need to be adapted to fit your PC.
I plan on using 2" when i get around to finishing mine as i went with a 2" PC for simplicity and cost effectiveness.

[Zak Griffin]

A blockhead is significantly cheaper than a 180°. You only need a single 2" (of whatever your PC is going to be) 90, rather than a 4"-2" and 2x 90's.

A blockhead also allows you to run a gin basket abive the RC.

[scythe]

I stand corrected then.

Are 2.5" elbows hard to find?

[Donny]

Cheers for the quick response fellas..
Copper pipe isn't an issue as I picked up an assortment of 2",2 1/2,3and 4 inch for $100 off the local classifieds .. :text-thankyoublue:
So I guess its going to be a blockhead .

[rash]

I stand corrected then.

Are 2.5" elbows hard to find?

I keep an eye out at the salvage yard for them. Check out their sink collections.... have scored a couple of copper 2" s-traps now off old dodgy looking sinks. Wriggle them off and throw in with the rest of of your collection for pricing. Pretty much get them for next to nothing. Example of one in my bubbler build.
Ash

[Lowie]

As Zak said, the blockhead can also be used to make gin by dropping a basket in. As for your boiler, I turned mine upside down and cut a 4" hole in the bottom and used the original 2" opening for my drain - 6 of one, half a dozen of the other :smile: . I can't see what difference a smaller outlet to the still (if you use the 2" port and a 2-4" adapter) would make a difference, the vapour is still going to rise. Check out my build thread and you'll get the idea.

[Donny]

What is the go with the basket ?? Do you put stuff in it to flavor the spirit ?? Sorry havent done any research on gin baskets ,is there a preferred size
..Can't turn boiler up side down as it already has heating element installed and too much work to change it ..
I have already got a 4" feral so thinking I might just tig it onto boiler and be done with it ..