Pot still fittings

Simple pot still distillation and construction with or without a thumper.

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nantahala
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Pot still fittings

Post by nantahala »

Hey guys!

As much as I've read and researched, I can't find a precise answer to my question.

I'm fabbing up a pot-still, the usual pressure cooker route.

My only question is how to fit the copper pipe to the pressure cooker lid. I don't want to solder and I don't want to use a cork or stopper. I'd like to only use pipe fittings. Has anyone come up with a good way to do this?

I'm not a plumber by any means, and I don't have any experience with fittings. I can imagine how it would work but I'm not sure what types of fittings are best to use for steam.

If anyone has a clear answer, I'd really appreciate it.
Tater Patch Kid
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Re: Pot still fittings

Post by Tater Patch Kid »

I use a male and female with copper washers between, inside and outside. U can also apply some flour paste coating the washers for a bit of sealant. My son in law has a pot lid useing male and female, he said he realy put the torque to them to cinch them down, My pot lid used a fitting similer, shorter threads, First try would of used a thick gasket to take up the gap.
Good Luck !
nantahala
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Re: Pot still fittings

Post by nantahala »

So, if I use copper washers, and really crank them down I shouldn't have to worry about leaks?


Is there any high enough quality rubber o-rings or gaskets that will not leech into the steam? I really want to avoid using the flour paste because my current set up uses it and I'm really tired of the mess.

Like I said, I'm unfamiliar with fittings and terminology, I'm having some trouble imagining what you're talking about.
Tater Patch Kid
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Re: Pot still fittings

Post by Tater Patch Kid »

Your copper washers start in a soft condition so there is not much use for sealant as i said, I used some paste on assembly and never disassembled after that. Same principle as Automotive brake lines connecting to your brake caliper. My original pot lid never had problems. My soon to be son in law uses some kind of o-ring :cry: and i can see some damage to them. I would never use anything on the inside except teflon or similer. Just make copper washers but make sure they are flat. :?: After working washers to a flat condition heat them up again to make sure they are in that soft mallable condition then cinch the male and female and you should not have any problems.
What size fittings are you thinking of useing???
nantahala
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Re: Pot still fittings

Post by nantahala »

wow, I didn't know I would need to fab up the washers. Should I just slice off a peice of line and beat it flat? Sorry, I'm totally green.

I was gonna go 3/8
still crazy
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Re: Pot still fittings

Post by still crazy »

You can get copper washers at a muffler shop a lot of times, or perhaps your local auto parts store.
Daddy used, to say " Any landing you can walk away from is a good one"
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myles
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Re: Pot still fittings

Post by myles »

OK lets clear up a few issues.
1. The pressure cooker is stainless right? NOT aluminium.
2. You don't mind cutting holes in the lid to permanently fit your still connector?

If both are 'yes' then we can fix it for you. Cutting copper washers out of sheet is easy. If you use a compression fitting with either a proper tank connector, or a male and female threaded fitting it will work. Use a copper washer on both sides of the stainless hole and tighten it up well. the stainless hole edge will cut into the copper washer for a good seal.
Braz
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Re: Pot still fittings

Post by Braz »

To anneal the copper washer you need to heat it to a "dull cherry red" color and then let it cool on it's own. Don't quench cool it. It will then be soft enough to conform to the fittings when you torque it down.
Braz
nantahala
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Re: Pot still fittings

Post by nantahala »

myles wrote:OK lets clear up a few issues.
1. The pressure cooker is stainless right? NOT aluminium.
2. You don't mind cutting holes in the lid to permanently fit your still connector?

If both are 'yes' then we can fix it for you. Cutting copper washers out of sheet is easy. If you use a compression fitting with either a proper tank connector, or a male and female threaded fitting it will work. Use a copper washer on both sides of the stainless hole and tighten it up well. the stainless hole edge will cut into the copper washer for a good seal.
yes stainless, and I'm fine with drilling.

So I need to use compression fittings instead of flange fittings?
myles
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Re: Pot still fittings

Post by myles »

Sorry for the delay, you can use either. Flange type bolted on or compression type it does not matter much. It is just a case of what is available. I fitted compression element mounts that required a 60mm hole to be cut in my keg. These are sealed with thick cork washers underneath copper backing rings.

Image

The drain is a standard tank connector - I just replaced the two rubber washers with hand cut copper ones. 1 inside and 1 outside the keg. With a bit of silicon sealant on the threads outside the keg it is leak proof.

You can silver solder a compression fitting into a stainless pot - solves the washer issue. You could also solder a copper plate into your lid. That opens up all sorts of copper to copper seals
nantahala
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Re: Pot still fittings

Post by nantahala »

Alright,

So basically, I just need to grab a male and female fitting and drill out a hole to accommodate them, then make a flange fitting for the tubing to thread onto the bitting on the pot.


Also, I should put a copper washer on either side?
nantahala
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Re: Pot still fittings

Post by nantahala »

Ignore the above post.

I decided to go compression fitting. I'm still having trouble visualizing how to make it air tight around the cooker lid.

Is there anyway some body could upload some pictures or something?
blind drunk
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Re: Pot still fittings

Post by blind drunk »

I'm still having trouble visualizing how to make it air tight around the cooker lid.
Maybe? http://homedistiller.org/forum/viewtopi ... =1&t=14177

My pressure cooker used to seal up when heated, without the rubber seal. In fact, it was given to me without the rubber seal. I would pre heat by boiling some water first, empty the cooker, fill with wash or low wines and then start the distillation.
I do all my own stunts
myles
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Re: Pot still fittings

Post by myles »

This is a 2"compression type tank connector fitted to a stainless stock pot. The compression connector has a flange on the bit inside the pot and a big backing ring that screws down tight. It is a really easy option.

Image

On this one I soldered the exposed thread to the backing ring, and also the backing ring to the pot. Just to make sure that it was vapour tight. When it was in the acid bath to clean up the flux residue, there was some unintentional copper electroplating onto both the solder and the stainless where the flux had been. Not enough for a proper electroplating job, but I left it - just for novelty value.
nantahala
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Re: Pot still fittings

Post by nantahala »

Thank you so much for the detailed help myles.

I guess my problem was that the hardware store I was buying at didn't have anything that would seem to work well for me. I found some fittings similar to what you showed but none of the flanges seemed big enough to make a tight seal. I'll have to try and find some better fittings elsewhere.
nantahala
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Re: Pot still fittings

Post by nantahala »

Did the fittings look something like this originally?

http://img.directindustry.com/images_di ... 372950.jpg" onclick="window.open(this.href);return false;" rel="nofollow

I found some pieces like this when I went to the hardware store, but the flange bit doesn't seem broad enough to put enough pressure on the lid. It seems if I torqued it down enough it would just strip through the lid. They didn't seem to carry any big backing rings like in the picture, that's the stuff I was really looking for.

I can imagine how the pieces would fit together in my head, but I can't seem to find the pieces I need at the store. These all seem like pretty standard fittings.
myles
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Re: Pot still fittings

Post by myles »

No that is a completely different thing. That is a male thread that screws into a female version and is intended to make a joint. NOT really intended to be fitted through a wall. However I have done exactly that on my thumper because I wanted to have a compression coupling both inside and outside.

What I am talking about is this
Image

The inner bit that goes through the wall has a wide flange to go on the inside. The compression ring also has a wide flange. They trap the wall and you also have another compression nut on the end with an olive to seal to the tube.

With these plus 2 extra washers you get a good seal onto stainless steel even without soldering it afterwords. That just makes it indestructible - and real difficult to take off again. :)
nantahala
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Re: Pot still fittings

Post by nantahala »

Myles you're the man! thank you so much for being so helpful!!!!


One last thing, any idea what that piece is called or what its intended use is?
myles
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Re: Pot still fittings

Post by myles »

Not sure where you are but here in the UK these are just called tank connectors. They are designed for attaching tube to flat sheet containers. These ones do have the end stop to prevent the tube from going into the tank - but the other sort are available also.

My keg elements are fitted with essex flanges. similar principle but the flange on the inner bit is a seperate item and the whole unit is assembled from the OUTSIDE of the container.

Image

These are sometimes called bulkhead connectors, although these normally have a threaded bit sticking out inside the tank too.

You can use the normal male / female threaded sections too, but will probably need to solder a washer onto each 1/2 first to create a wider contact area with the wall.

It is much easier if you are working in copper instead. There are all sorts of ways to attach a copper tube to a copper sheet. I have tried a few stock pot variations and it is much easier if you can make it a hybrid with a copper top fitted. I would be tempted to cut a disk of copper a few inches across and rivet it to the lid and solder the two together. Then cut a hole in the disk and fit your pot riser to that.

Image
Image

It is not pretty on the inside made this way with the flared hole, but it is very functional. I awyays say to try and convert to copper as soon as possible if using a stainless boiler.
nantahala
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Re: Pot still fittings

Post by nantahala »

I'm in the US.

I will try to find a tank connector somewhere. While the copper seems the best way to go, I think it may exceed my skill level at the moment.

Out of curiosity, why is copper so much better than brass? (sorry I'm such a noob!)
myles
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Re: Pot still fittings

Post by myles »

I did not explain that very well.

You CAN attach copper or brass fittings directly to your stainless pot. It is not exactly easy, it is simple to get wrong, I have done it before and I would NOT do it again.

A far better option IMO is to cut a 5" or 6" hole in your stainless lid and fit a copper plate to cover it. You can rivet and solder if you like, or bolt it together with a safe gasket. Either way it is intended to be a permanent or semi-permanent fit. You have just converted your stainless pot into a hybrid copper/stainless one.

Image

This was hard soldered onto the stainless bowl with 56% silver solder for a rock solid permanent joint. These days if I was to use a stainless pot I would fit a copper plate or bowl to it first.

All your still fittings are then attached to the copper plate which is REAL easy. Also way more versatile. You want a 4" opening into your pot still for cleaning? Working in copper it is no problem. If you want a 4" fitting that will cost you.

With a copper plate fitted you don't need ANY fittings to connect your pot still neck. You can flare copper tube and solder it onto the plate.

Not saying don't do it. This was an early thumper I built just to show that you can solder copper tube directly into stainless.

Image
Image

Just saying that I don't do it any more. Personally I prefer to build in copper and leave stainless to those that like to work in it.
nantahala
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Re: Pot still fittings

Post by nantahala »

Wow myles, that is some great info, but a litle beyond my skill level at the moment.

I've found some fittings online, so I guess ordering one will be my best option.

I was hoping you could look at the page and tell me which size will fit my needs best.

My pressure cooker is 8quarts and I have a section of 1/4" copper tubing, but I can go to a bigger size if needed.

http://www.fastfittings.com/brass-bulkhead" onclick="window.open(this.href);return false;" rel="nofollow
myles
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Re: Pot still fittings

Post by myles »

I am going to PM you.
nantahala
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Re: Pot still fittings

Post by nantahala »

Okay guys, so yesterday I was finally able to get everything put together.

I ended up using one of these, http://www.amazon.com/gp/product/images ... ting-goods" onclick="window.open(this.href);return false;" rel="nofollow

with one of these on top. http://s7.cdn.hardwareandtools.net/s7/z ... &locale=en" onclick="window.open(this.href);return false;" rel="nofollow


I used copper washers on both sides of the bulkhead and everything seems to be sealed up perfectly tight.

Now, my only question is how to add a thermometer. I've got a regular culinary thermometer, but I'm not sure how to add it to the pressure cooker lid. Should I use some kind of gromet to attach it?
myles
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Re: Pot still fittings

Post by myles »

IMO the fittings you have are just fine for your thermometer. All you need is a bung of some safe material, PFTE thread tape, cork, distillers tape to go inside that compression fitting. Put the compression nut on your thermometer, push it through the bung and use the compression fitting to tighten it up for a good seal.

I had something just like that on my first electric 5 litre still.

Another fitting exactly the same - but a bit bigger - and you are good to go. Some folks will disagree but I wouldn't use anything less than 1/2" even on a boiler that small. I ran my 5 litre pot on 3/4" that fed into a 1/2" in 3/4" liebig.

EDIT. I never took a photo of that pot but this is a stock image. I threw out the 2 rubber gromets and the pot head. Fited 2 fittings similar to your ones but actually UK style tank connectors. Middle one was 3/4" and the thermo one was 3/8". It is gathering dust in the back of a cupboard somewhere.
Image
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