brass for a still?

[spencoid]

i just bought a heavy tube that i thought was copper when i saw it. the patina looked like is was copper and it was in with a bunch of other copper tube. turns out it is brass. i bought it to make a gin back for my still which is mainly glass. thought it would be easier to make a big opening than with glass.

so the question is, is brass not good in a still? it seems to be a yellow brass not the old very red stuff that was mostly copper. i can silver solder it together and then tin plate it, i guess if that would be better but of course this will be a lot more work. i have a bunch of pure tin and various fluxes so i can probably get a decent finish. my silver solder is 15% silver Bcup-5 of the type used for refrigeration work and it could have some cadmium in it as one of the "other elements .15%" it is not the stuff made for stainless steel NSF applications that is certified cadmium free.

if i soft solder with lead free plumbing solder it might be difficult to tin it without it falling apart.

if this is good solder for stills in places where more strength is needed than soft solder, it will be very good because i have 35 pounds of it and never found much to do with it

[NZChris]

Check it for lead. I have heard that a lead paint test kit should work for this.

[spencoid]

i think it is old enough that it does not have lead in it, not the chinese recycled stuff but testing is a good idea. the solder does not have lead in it or if it does it is a tiny amount. lead would make it a real crappy hard solder. if i tin the brass that should protect from any lead in the brass, shouldn't it?

[Truckinbutch]

Sounds like a lot of work to incorporate a questionable material into your still . I , personally , would not use it .

[Danespirit]

i think it is old enough that it does not have lead in it, not the chinese recycled stuff but testing is a good idea. the solder does not have lead in it or if it does it is a tiny amount. lead would make it a real crappy hard solder. if i tin the brass that should protect from any lead in the brass, shouldn't it?

"If it does it is a tiny amount"....
If I shoot myself a bullet in the head and survive, I'd just be a tiny step further to the grave.
Now think again and think hard about that kind of logic..!!
What happened to the safe options about building a still..?
Is it so hard to resist the temptation of using questionable materials, that it is worth risking your (and your beloved ones)health for an easy solution..?
Would you still live a happy life knowing that your poor choice of materials, would be the cause of others suffering and early death..??

Edit: Oh...btw..lead ain't the only material that WILL cause health issues..Zinc is also a component in some brass alloys.

[Kareltje]

That is exactly why he askes about tinning the inside.
Oh: and zinc is even less toxic than iron. Let alone copper!

Brass couplings are used in great amounts in waterplumbing. But a brass pipe is something different. And hot alcohol is different from cold or even hot water too.

I have not yet seen solid information of transferring metals from the still by the hot ethanol vapour into the distillate. And I doubt if anyone here has seen it.

I use brass couplings I buy at a hardware store and I notice a discolorization. But copper and bronze get a patina too and the exposed area of brass is small.
But a brass pipe? I doubt if I would use it in contact with the distillate. Maybe as a mantle for a condenser?
But I do not know how to tin a tube.

[Wouter]

Long term exposure of brass to an acid may some of the zinc to slowly seep out of the brass. This process is known as dezincification and it damages the structural integrity of the brass. Wether or not this happens is really depenend on the zinc content of the brass, the higher the content the more susceptible it is.
Scalding hot ethanol may be considderd acidic.

Wether or not it is hazardous for your health? Not a clue.

[spencoid]

ok, forget the brass. the only brass in the still now is a tee for draining the boiler. never exposed to vapor or alcohol stronger than what is in the boiler. also only has much going through it when the still is drained. everything else is copper glass teflon and stainless steel. i think my current gin back is really fine, just was thrilled when i found the copper tube that isn't.

i think that triple tinning it would be fine but it is a real pain to do. i have a pile of copper cookware that i plan to tin some day and because it is such a bitch haven't yet

i think i will practice my stainless steel welding instead.

[zapata]

Good call, there is plenty of evidence of metals from the still ending up in the distillate, it is certainly a known concern in the industry.

Personally I wouldn't bother, but for some reason if I felt I just HAD to, I would feel comfortable "tinning" the entire product side with an appropriate solder. It would be difficult, but not necessarily prohibitively so. I think that would also meet the forum's rules of nothing but copper, stainless, and appropriate solders. But yeah, why bother?

[spencoid]

i am going to use a weld type 3" stainless tee and make a plug for it after cutting the side arm short so i can angle the sieve of bots in easily. i thought about using a tri clover tee and cutting two of the flanges off but the side arm would be longer and interfere with putting in the bots. so the plan is to make a tight fitting teflon plug or cap that might have an oring or maybe i can make an integral seal of some sort. if i use an o-ring it will be at a dead end just to prevent leakage and will not have distillate washing past it so i don't think it will be a problem if it is EPDM. i also have some teflon tubing that i could probably use to make a seal instead of the o-ring. i found a tee with short arms on e-bay and ordered it. i might be able to figure out some way of making an expansion plug of teflon or maybe some kind of twist lock. otherwise i will use a pin to prevent the plug from falling out.

as i said earlier, i have a bunch of pure tin. it is 99.9% pure tin and it is a little easier to coat metal with it than using solder. i tin my own copper pans and although i hate doing it, it is not very difficult, just a very noxious process. since i am going to use stainless i don't have to worry about this.

i have a lot of metal from "copper" water heater tanks. it is thick and relatively easy to form. that is another possibility. i have cut these apart and made smaller tanks by silver soldering but now that i have a tig welder i would probably weld it instead. i think it is silicon bronze but would have to do more searching to really know. i also have a monel tank and i am pretty sure that is OK for a still. however it is still a complete tank and i do not want to cut it up unless there is a good reason for doing so. the monel is much tougher and hard to form. hopefully the stainless tee will work well.

[Danespirit]

That is exactly why he askes about tinning the inside.
Oh: and zinc is even less toxic than iron. Let alone copper!

Brass couplings are used in great amounts in waterplumbing. But a brass pipe is something different. And hot alcohol is different from cold or even hot water too.

I have not yet seen solid information of transferring metals from the still by the hot ethanol vapour into the distillate. And I doubt if anyone here has seen it.

I use brass couplings I buy at a hardware store and I notice a discolorization. But copper and bronze get a patina too and the exposed area of brass is small.
But a brass pipe? I doubt if I would use it in contact with the distillate. Maybe as a mantle for a condenser?
But I do not know how to tin a tube.

Although zinc is required by the human body for the production of many essential amino acids, supplemental zinc can prevent iron absorption, leading to iron deficiency and possible peripheral neuropathy, with loss of sensation in extremities.
So I think we can conclude zinc ain't the best material to use in a wet, hot, and alcohol laden environment.
Yup..! I used brass for my Liebig condenser which can be seen here: http://homedistiller.org/forum/viewtopi ... 50&t=59501
However, it only used for the outer shell and the connections.

Spencoid...instead of using EPDM, just wrap it in a couple of round PTFE tape.
I use that trick for sealing my "stick in" thermometer on one of my stills..never let me down.
I don't think the idea with the Teflon tubing would work. Such tube is very rigid and there would still be an issue with the ends.
You have access to a TIG welder...that's just excellent..!
Copper can be TIG welded, with or without filler material..you can even weld copper to stainless..no problems.
Your current plan with copper and stainless is way better than to use brass.
Monel is a very expensive alloy. It's also hard as f... and not the easiest to form and/or weld.
Maybe you should use that tank for something else...it would be a shame to cut it.

[spencoid]

i think i figured out how to make the plug for the stainless steel tee. i had been using teflon wrapped EPDM o-rings for all the teflon to glass joints thinking the teflon was too hard to seal well. if i machine the groove for the glass in the teflon rings, they do not leak at all with moderate tightening of the allthread rods that hold the whole thing together. i think i can make a cap or a plug for the tee without using an o-ring. i will make a flange for the tee with threaded studs in it and use wing nuts to hold the teflon plug on. there will be a groove to fit the tee metal and i can always put an o-ring in there if necessary. the teflon tubing i have is very small diameter sort of like capillary tube. if i fit it carefully into the groove it might work as an o-ring. this did not work with the glass because it is too small diameter but with the .065" metal of the stainless tee it might compress more easily. maybe i will make the plug with a hole for a glass window. waiting anxiously for the tee so i can start this. i have some sugar wash almost ready and plan to make one batch with the current setup and then wait to try the new one and see if i can get more flavor.

[spencoid]

got the new 3" stainless steel tee and it is a beauty. can not tell if it is chinese or not but the thing is perfect. dimensions are right on and the finish is gleaming. all for $20 with shipping i got the shortest tee i could find so the placement of bots will be easy. since the bore of the side arm is so perfect i was able to make a plug of teflon with an oring in a groove to seal and hold it. no need for clamps etc. this oring will be a wear item and need to be replaced occasionally. it is not in the vapor path and the teflon fits to withing about .005" so i doubt anything will leach from the oring into the distillate. still i might buy some expensive fluro orings for this location since it is now the only even vaguely questionable material in my still. now i can experiment with different containers to hold the bots. i can make it so that all the vapor to the main condenser has to pass through the bots because the tee allows me to cram in a bag of material as big as the diameter of the still and there are no sharp edges to catch anything. also i do not have to worry about the drilled glass breaking although that has only happened on a piece that i had bouncing around in a box of junk and had a hole right near the end of the tube. will take and post pictures once i get it assembled. finally, with the help of members of this forum, i think i am getting very close to a pretty decent still.

BTW, i added a simple level switch that shuts off the heater if the boiler falls below a certain level. it was extremely easy to do without having to find one of my liquid level controls and figure out how they work although the group does not approve of unattended operation of a still and i do not intend to do this other than during preheat, i think that adding as many safety features as possible is warranted. the teensy arduino that runs my still is so small, and cheap that it is a good way to add safety circuits to anything. the teensy has touch sensing on multiple pins. all it takes to make a liquid level sensor is to stick a probe in the boiler sight glass. of course the same can be done with a bridge and a comparitor but that has to be soldered together. i have screw terminal boards for the teensies and can hook them up to anything in a matter of minutes and can program any function i need instead of wiring it.

[spencoid]

got the still assembled but no time to try it today, maybe tomorrow. here are a couple of pictures of the new "gin back" the quality of the tee is amazing for a $20 part. the plug fits tightly so will not fall out. an o-ring keeps it in place and because of the tight fit does not expose the distillate stream to the o-ring. will try to find (and hopefully can afford) a fluroelastomer o-ring.

the window in the plug has an aluminum plug that holds it in place but the aluminum is only on the non vapor side of the glass window. that big chunk of aluminum was found in my scrap box almost as it is. just needed a little resizing. it was a cutoff from something i made years ago. pays to save everything

[spencoid]

my still is working amazingly well now. i actually had quite a few things to fix. the new tee for the bots really lets me get a lot of flavor. i am now experimenting with pepper. pink pepper corns seem to add an interesting flavor.

the first batch i made with the new gin back came out good tasting but it was surprising that i could not get it over 155 proof. i discovered that the new reflux condenser was totally clogged with solder. all the reflux that was occurring was due to the height of the column and its dissipation alone. the only reason i discovered the blockage was because i had made a new heat exchanger for the cooler. i suddenly remembered that i have some spare coils from 1910 vintage Ruud instantaneous water heaters. these are very nicely wound 1/2" copper tube in a shape that is very good at absorbing (or dissipating) heat. i put a set of these in a 5 gallon bucket and put a high speed axial fan on top. the only problem is that the tubing was full of crud and it took me a while to figure that out and clean everything. also added a filter to the output from the cooler so crud can not get into tieher of the condensers no matter what. since i have a flow meter monitoring the flow and shutting down the still if flow stops, the filter is not a liability. once i run the still for many hours without collecting any more crud in the filter, i will probably remove it? that is when i discovered that the reflux condenser was totally non functional. got it all cleaned out and made a new condenser. it works great now. i can get 100% reflux at 50% heater power, that is 2500 watts. i can also get a very fast output of medium strength alcohol. an added benefit to all these improvements is that the head temperature now seems to really indicate something. before it was sort of random. i just could not figure out why it varied so much although i was making decent product.