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HedgeBird's Still Build


HedgeBird

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So for better or worse I have undertaken to build my own still. I thought about starting a thread a ways back but decided not to. As I am not a professional builder posting details about my plans on a forum of professional distillers and builders is, to be completely honest, somewhat intimidating. In the end my posting details and getting feedback will hopefully lead me to have a better, more functional and safer piece of equipment, even if I have to suffer some negative feedback or display my ignorance in certain areas. Hopefully some of you will find this thread interesting and it will either inspire you to build your own, or discourage you from what is honestly a daunting task.

The design I came up with is modeled on the German builds, and the plan is to end up with a still that works, and looks, just as good as as any professionally built machine. Bootleg style stills are great, and I have no criticism for ones made from 50 gallons drums, but when another distiller visits my distillery I would rather them ask "is that a Vendome or Carl" rather than "where did you source your barrels from?" Time will tell if I am going to be able to pull that off, but hopefully its presents an idea of what I am going for. Basically built a still for under $15,000 that looks like $60,000.

So the design is a 150 gallon, steam jacked still with a dephlegmator, four valve plates and big 6" sight glasses that stands 12' 6" tall overall. The base of the still is a 150 gallon commercial kitchen kettle that I purchased used back in October.

Most of the still body is .093 copper plate that I have slip rolled into various pieces. The column and dephlegmator have an 11.25" inside diameter and are 4 feet and 2 feet long. The current issue I am working on is how to seem-up the pipe sections. I have gone back-and-forth and forth again on weather to but-weld the seem directly, or place a 1" strip of copper on the outside of the seem and rivet and soft solder that in place. Last week I did a test of wet-soldering (some people call it tinning I think), riveting and then heating and sealing a small disk. This technique worked really well and I could not have been more happy with how the rivet sealed, and how strong the connection is. Tonight a friend and I welded two scrap pieces of .093 plate. I am really happy with this test section and now I think I am leaning towards welding all the external seems. If anyone has input I am open to hearing it.

Basic idea of what we are going for..

150GPotStill.jpg

Sample seem options. Rivet and wet solder / welded..

seem-options.jpg

dg1.jpg

dg2.jpg

dephlegmator - dry fit and waiting to be placed in a seemed-up pipe!

More details and pictures to follow!

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Ok, I have some suggestions. First off I would advise against soldering the seams. For a professional situation they are not strong enough. The copper when heated, for distillation, will move a ton. Believe me. When my 1" copper coil in my still is heated you can see it move like crazy.

Welding or brazing would be preferred. As far as welding it, I weld professionally, welding small bits of copper together is NOTHING LIKE welding large pieces of copper. When welding or brazing large pieces of copper it's a whole different ball game copper is a extremely efficient heat sink. I have a 310 AMP tig welder and trying to weld up an oil tank for my harley, out of copper, is not working. It's 6" diameter tube with end caps and my welder can't budge it.

How did you weld the test piece, looks like tig? What did you use as filler metal?

If you used stick welding it might work or get copper wire for a mig welder as these weld a little differently than tig. But Mig and Stick don't usually create water tight welds.

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I totally agree with Absinthe Pete. Don't use solder, even silver solder. A biolermaker / stillmaker told me that alcohol eventually eats holes in silver solder.

When welding large sheets you might find it helpful to get someone to heat the joint with a propane torch, just in front of your weld.

(now I am half expecting someone to come back and say propane and TIG shield gas don't work together? It worked OK for me)

I don't know what gear you have, but don't use a small TIG. IF you manage to get a good weld it will be very slow and frustrating

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PeteB is correct, but propane won't work very efficiently. What you have to do is preheat it, and keep it heated as you weld, by getting it cherry red with an oxy/acetylene torch, which takes two people to do. The problem is when your done the copper will be VERY soft, like bend with hand soft.

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Well, it sounds like there is really no question about the option to be used. The sample above was TIG welded and the filler we used was just plain copper wire. My friend has a fairly large welder and did not seem to have any problems with these smaller pieces. He tried out a few amperages and ended up at 230. Thanks for all the tips, and when we get to doing the real seems (hopefully next weekend) ill make sure we get/keep it nice and hot.

APete - I remember seeing pictures of your still right after you finished it. That thing is a beautiful beast of a machine!

PeteB - Your still is super classy and all the copper is inspiring - I love the brick foundation as well.

ViolentBlue - I don't know if you recall, but back In October I had emailed you with some questions. (had to change user names since). I have referenced that conversation a number of times now and I am not sure if I would have been confident enough to pull this off without your input and affirmation that my design was not totally ridiculous. Your already on the short list for a bottle from the first batch!

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PeteB is correct, but propane won't work very efficiently. ....

That would depend on the size of your propane torch. I have a couple of very large ones.

But I will admit I did use oxy/propane torch for my preheating. Just tried to save a few typed words but ended up with more.

Also straight propane flame goes out when used inside the still because it very quickly consumes all the oxygen, then one could end up with an explosive mix inside when the oxygen returns.

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If you don't have an oxy-acetylene rig, you could also use MAPP gas (or what is sold today as MAPP, it's not really MAPP any more, but pretty much equivalent). MAPP is a lot hotter than propane. Look for the yellow (metal) bottle. You may go through the small (plumber size) bottles quick, so get a few. Also get a torch that can put out a lot of heat, like a Turbo Torch. If you go with the propane, the torches used for torch-down roofing put out around 140k btu.

Carter - re: 1" copper coil, I take it this is your steam coil? Are you using LP or HP steam?

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I run a Carl still that has an amazingly effective de-foamer between the boiler and the column. Don't know if you're planning on including such a device, but it is quite handy. Let me know if you need any more details.

Also, are you planning on being able to have your plates operate both open (defeated) and closed (operational)? This is an option that I have found to be invaluable.

Out of curiosity, is your kettle stainless? How are you mating it to the rest of your equipment?

Nick

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Nick, I think there may be a few of us who would like to find out more about the de-foamer.

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I have a few small propane torches a small oxy/mapp welding/cutting torch with a tiny tip and a MAPP torch with the standard ignition trigger torch. Even with the MAPP torch I am not easily able to get stuff hot enough to braze. I have done a few small pieces but it takes a long time and is hard to get a nice clean connection. I have about 20+ 1.5 inch pipe connections on the dephlegmator alone so I definitely need more heat. I am debating getting a really big propane tip that I can run off my grill style tanks, an acetylene/air (not oxygen) turbo torch, or just dragging everything over to my friends foundry and going at it with his oxy/acetylene torch.

The acetylene/air torch I am looking at has the “MC" or "B" Tank Connections. Seems like it would work good for at least the smaller connections, and possible for the larger ones if I back it up with a helper on a second torch. Anyone ever use one of these style torches? It would be nice not to have to use oxy/acetylene for every braze joint as I will need to schedule time in my friends shop for that..

Nick, I am also curious about the de-foamer. Please do post some pictures/details!

I have designed in a plate by-pass system. At this point its fairly simple 3/4 pipe out the bottom of the plate through the column wall into a down pipe and valve, and then to the plate below. The layout I have right now has just one valve per plate so I will have to "defeat" the plates in order from top down. (look at me using my new terminology defeated/operational vs. open/closed!). Going with more valves, or three way valves would give more options, but it seems like overkill.

The kettle is stainless, about 2" thick (double wall/jacket) and has a rounded half-circle lip on the top.. I have two 34" inch stainless angle rings with bolt holes. One will get welded to the kettle, and the other welded/brazed to the copper body of the still. These flanges then get bolted together with a gasket between them. The leg-out of the angle rings protrudes about an inch past the sides of the kettle. The plan is to insulate around the kettle, and then hang a thin piece of rolled, patterned stainless from the lip of the flange to enclose and protect the 1" insulation. Photo of rings and sketch of connection below..

Anyone have any suggestions on suitable insulation. Also, how does everyone feel about sheet cork for gasket seals?

angle-rings.jpg

kettle-edge.jpg

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No reason to use sheet cork these days. If you did you have to make sure it's pure cork. Most of the time the cork is glue together and you can't use that.

For a flange gasket just get one made. Around where I live SF bay area there are a ton of gasket makers. For the size you have, even in custom made, it would take an hour or so to make and cost about $30. And that's in viton. If you don't like viton you could get any material you want, but viton's best in my opinion.

Just do it right and don't spend the money, use oxy/acetylene.

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Regarding the insulation, check out Armaflex insulation; it comes in tubes for pipe use and also in sheets. I have used the pipe version with good results and I am planning on using the sheet version for my still. It comes in 1" thick and at that thickness it's R 4.2. You glue it together with their heavy-duty contact cement.

http://www.armacell.com/www/armacell/INETFAQ.nsf/vFrame1/CD493FAD5EF77ECE8025707C00437E3D

Did you heat angle stock and bend it for your flanges? I have made drawings for a part with a similar purpose, but I had thought about having it cut by water jet.

Regarding your stainless cover, it appears to be hung from the top flange? Maybe it's better to attach it to the bottom flange, so it could be mounted permanently and you wouldn't have to remove the insulation cover when you removed the lid.

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HedgeBird said "The acetylene/air torch I am looking at has the “MC" or "B" Tank Connections. Seems like it would work good for at least the smaller connections, and possible for the larger ones if I back it up with a helper on a second torch."

For the money you think you will save, it will be well worth buying yourself an 0xy/propane torch with a big tip. If it is too big you can always turn it down but you can never turn a small one up far enough. Acetylene and propane tips are slightly different but will work with the other gas, although not quite as well.

In Australia we rent the oxy and acetylene bottles by the month. Don't know if US is similar.

If you use propane you can use your own cylinder and save one rental. Oxt/acet or oxy propane produce similar heat.

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So I suppose that I should preface this by saying that I am posting this because I love my Carl still so much, and I want to show off how well designed it is. For all I know, this is a patented or otherwise proprietary design, and I'm not encouraging anyone to copy it. For reference, our still capacity is about 300 gallons.

post-1480-0-46141900-1338699862_thumb.jp

Anyway, basically there are three 3" pipes, two leading from the boiler to the column and one leading from the column back into the boiler. They are all capped with identical bronze mushroomy looking fittings (I've seen them somewhere else before... I want to say they are some steam-fitting vent cover or something).

The foam travels up through the two 3" pipes and is sprayed through the mushroom fittings back down towards the remaining pipe. This breaks up the foam into vapor and liquid. The vapor rises up the column, and the liquid drains back down through the remaining pipe. I imagine that the fact that this remaing pipe also has a mushroom fitting acting like a spray ball has something to do with additional de-foaming.

It works quite well. Obviously, it is possible to apply enough heat to the boiler to force foam through the de-foamer beyond the de-foamer's ability to cope. However, it is quite amazing how much foam this simple design can dissapate.

Nick

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Here is something to thing about with your non-cork seal.

Your flanges are made from reasonably thin stainless and the mating surfaces will be far from perfectly flat. This means you will need a fairly thick compressible gasket.

I had the same problem. But it was very east to solve and I am very happy with the result.

I am not sure if it is the best product but I used closed cell neoprene foam o-ring. I was told it was good to 140 deg C. I just measured the length and cut the ends at an angle and glued together with superglue. There is probably better glue but that is all I had.

In your case I suggest you place the o-ring just outside the bolt holes, sit the top on and fit the bolts but leave the nuts quite loose.

The weight of the column will be enough to compress the soft o-ring to give a good seal. (I have seen a still made by a boilermaker and he used half inch diameter stainless bolts on 2, half inch thick machined flanges. Looks impressive to some but there is no need.) This is not a pressure vessel, there should not be more than 1 or so psi in there

One very good safety feature about the soft o-ring and loose bolts is that if there is any overpressure the o-ring will get blown out in one spot and releive the pressure. If the nuts are loose the top can also lift slightly. The only reason to have bolts is to prevent the top falling over if it gets bumped.

If you get a negative pressure inside the still the o-ring will probably get pushed into the still between the bolts by atmospheric pressure, and prevent your still from imploding. This negative pressure releif will work best if the flanges are not perfect. The atmosphere will push down on the top of the still compressing the gasket and making it tighter. An uneven flange will have a weak spot where the o-ring can push into the still.

You should have your normal safety valves of course, this is just an extra backup.

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Regarding the insulation, check out Armaflex insulation... I am planning on using the sheet version for my still...

You might want to research this decision a little further, Jedd.

I love Armaflex for cold applications and use it all of the time. But I've never seen it used at boiling temperatures before. A quick check of the product sheet in your post above revealed that the high temperature spe for Armaflex is 105 degrees C. Since the temperature of steam increases with pressure, I believe you'll be reach 105 C at a pressure of around 5 psig...

Fibreglass or another insulation with a significantly higher maximum temperature spec might be more appropriate for a steam application.

Nick

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Dude, I hope you're joking, neoprene and super glue?

I am not joking, but please note I did say

"I am not sure if it is the best product but I used closed cell neoprene foam o-ring" (the outside surface of this product is sealed, not open like a cushion foam)

I went to 3 gasket suppliers and this is the best option they came up with.

Firstly, what physical or chemical properties are wrong with these?

Secondly, what would you or anyone else recommend for a soft gasket?

I boiled some of the o-ring for a few minutes to check it did not taint the water or my nose before I used the neoprene.

If I have stuffed up thankyou for pointing it out,

ps. I am now not certain they said neoprene was good to 140 C, but I am sure it was well over 100 C

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According to Cole Palmer chemical resistance chart neoprene is satisfactory to 120 F NOT C.

http://www.coleparmer.com/Chemical-Resistance

I'd rather see you the old stand by flour and water. Use a custom made gasket out of viton or silicon, it costs about $15-$30 depending on size then use flour and water on top and bottom tighten the bolts down, heat the still up and it'll harden and completely seal it.

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Jedd - I have access to a slip roller so I did role my own pipe and body sections, but I did not know anyone with the machinery to do the rings. I had my rings custom made by these guys: http://www.nmfrings.com I was able to specify the material, thickness, overhang size, number and size of bolt holes, etc. They also ground down the welds on the sides I requested so they would not be in the way of the gasket or copper connections. Turn around was fast and I though their prices for custom work was really reasonable.

Yeah, I am also not sure about the Armaflex: "With full adhesive coverage attachment, the surface to which it is applied may operate to a limit of 180°F (82°C)."

How about Nomaco Kflex steam pipe insulation for both gasket material and insulation:

http://www.drillspot...heet_insulation

Its NSF (National Sanitary Foundation) approved under Standard 169 for potable water or food service applications. It has a temp range of -297 to 300DF and only $36.91 for a 1/2" thick sheet that would be big enough for all my flanges.. its also available in 1" sheet as well for use as actual insulation.

The current design does have the stainless cover just hanging from the flange lip. Figuring out some way to attach it to the bottom would be better, and also probably look cleaner. Ill have to think about this some more!

Nick - Thanks for sharing details of your Carl. They realy are beutifull things! So with the de-foamer in place you basically have three 3" pipes leading from the boiler to the column and the rest is closed in with a plate? How much clearance do you have between the de-foamer and the first plate? If I try to add something similar I might need to adjust my plate height.

Violent - Would you conside brazing an option for the stainless to copper connection or do you think tig is really the only option? I will have 5 stainless to copper rings/flanges all told..

PeteB - Yeah, its probably fair to assume my big rings are far from flat and I will need a fairly thick gasket.

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