BanjoTed wrote:Apparently most brass has about 2% lead added to make it easier to machine. I think I read somewhere on the main site that you could theoretically have dangerous levels of lead in the wash but as long as as there is no lead in the downward sloping part of your column/condenser then you are all OK as the lead salts simply can not travel upwards in vapour form. It would still be nice to have someone confirm this.
There's been a lot of talking and some reasoned comment since this was posted but I don't think the question was answered.
Is it true that 'the lead salts simply can not travel upwards in vapour form'. ?
I'd really like to know because I have some brass in the 'upward' part of my pot still and don't want to do anything unsafe.
This is a site about the standards for drinking water tests done for lead on fittings. Look to see if the fitting has a NSF/ANSI Standard 61 on the packaging to see if it has passed.
My needle valve is a Watts model A-42 which is not lead free or NSF/ANSI Standard 61 certified but they do make one that is just a matter of finding it but both have Polyethylene inside which again could be a problem. Swagelok makes a stainless one with metal to metal sealing and PTFE packing but it is $95.00. http://www.swagelok.com/search/find_pro ... 716a4fa06c" onclick="window.open(this.href);return false;" rel="nofollow
Alot of money to avoid Polyethylene and tiny amounts of lead but I think i will go for stainless after thinking about it for a few days and have peace of mind.
"Alcohol: The source of and solution to all of life’s problems." -Homer Simpson
This brass lead fiasco has turned into one big headache. I was concerned about a galvanic reaction putting a stainless needle valve on copper tubing and I am reading it is suggested to use a dielectric union with dissimilar metals which is basically a plastic fitting which separates the two metals. I doubt there is a dielectric union for a one eight needle valve and it would introduce more plastic. Maybe back to a lead free brass valve.
"Alcohol: The source of and solution to all of life’s problems." -Homer Simpson
I have tried to say this nicely before but folks just don't want to pay attention. There are a few real easy solutions to the brass problem. Brass fittings are convenient, durable and they also look good.
JUST SOLDER OVER ALL THE EXPOSED SURFACES. There is loads of solder in a normal still, a bit more makes no difference.
I like to use a 56% silver hard solder for the job. In reality it is not that much different from silver plating the brass fitting. In fact thats a brilliant idea - someone please market silver plated brass fittings and let us bury this rediculous topic for good.
Yes lead in brass IS a problem BUT there are ways around it. Perspective is good. Brass in the liquid part of the boiler is not usually considered a problem. If you do not wish to rely on solder, then simply use inserts of thin copper sheet so that there is no exposed brass in your vapour path.
Brass is GOOD, you just don't want it in contact with alcohol vapour - but there are ways to avoid that.
bgrizzle wrote:
if you have to use brass... pickle it...
Why ask why???
I understand that your comment was not necessarily aimed at one person in particular, but if I may respond constructively;
If using brass is a problem I would really like to know how pickling has any effect whatsoever on that problem. I am not asking that because I use brass, or because I do not understand the options other than using brass, or how to make brass safe using mechanical means as just described by myles. I ask because a) I am curious to know and cannot see why a better understanding of the materials with which we work is a bad thing and b) if someone is using brass, and thinks that it will be made safe(r) by pickling, I for one would tell them that this is not the case. Pickling, as I understand it, will simply clean the item in question, leaving it to oxidise again, nothing more. So, if brass with lead content is unsafe, we can tell people not to use it, but I don't think we should tell people that it will be made safe(r) by pickling.
-Dan
Dan P wrote:
"So, if brass with lead content is unsafe, we can tell people not to use it, but I don't think we should tell people that it will be made safe(r) by pickling."
I totally agree with Dan. I can’t understand why some folks are so adamant that pickling is a miracle cure with absolutely no facts to back this up.
I have replaced all my brass with stainless.
"Alcohol: The source of and solution to all of life’s problems." -Homer Simpson
Wanker wrote:Dan P wrote:
I have replaced all my brass with stainless.
I don't know enough about pickling to comment and stainless compression fitings are expensive. Stainless sanitary fittings are a good option. COPPER sanitary fittings would be an ideal option for the home builder that likes to use copper, and fortunately there are ways to do this. Some folks are working on producing these on a commercial basis which is good.
In the meantimes possibly the best (not the easiest) option for the homebuilder that wants to use brass is this:
Take your standard brass compression fitting and drill out the end stops. Drill them out big enough to take a normal end feed slip fitting. Cut this to the required length and solder it inside the body of the compression fitting. Insert your copper tubes into the end feed connector to the mid point, and tighten up your compression rings.
You now have a cheap brass screw type compression fitting that is fully lined in copper. Possibly the best of both worlds.
I currently use a 2" brass connector on my column - between the VM section and the column - (that I intend to replace with a pair of festers copper tri clamp flanges). You need a BIG spanner to tighten a 2" compression fitting.
Dan P. wrote:So, if brass with lead content is unsafe, we can tell people not to use it, but I don't think we should tell people that it will be made safe(r) by pickling.
I agree.
An experimental corrosion study found no long term benefit of pickling brass, although it may cut the rate of leaching for a while: http://dx.doi.org/10.5006/1.3315907" onclick="window.open(this.href);return false;" rel="nofollow
You don't want the lead compounds leach into the spirit, right?
These compounds are formed with an ionic bond or metallic bond, so the boiling point is much higher than e.g. 100°C - the maximum temperature the vapor when a Home Distiller is producing spirits reaches. That means that they will NOT carry over into the product if the brass fittings are at the "increasing" vapor path in the still.
Sketch:
What do you think?
addition: That is why one can remove lead, nitrates, salts etc. from tap water with a normal water distiller.
Non-Native English Speaker. I'd appreciate if you would tell me my mistakes! Thank you and have a nice day!