Jump to content


Photo

Copper Still joined with Rivets

coppersmithing copper still rivets manufacturing of still

  • Please log in to reply
12 replies to this topic

#1 Okperioimplant

Okperioimplant

    Newbie

  • Members
  • PipPipPip
  • 36 posts
  • Gender:Male
  • Location:Oklahoma
  • Interests:Spirits, family, learning, copper

Posted 23 March 2013 - 11:09 AM

Just a question about rivets with copper stills. Is a joined seam of copper with rivets, functional to keep the sheets together and leak proof, or purely just decoration? Also, is the seam welded or soldered in addition to the rivets?

#2 PeteB

PeteB

    Advanced Member

  • Members
  • PipPipPip
  • 483 posts
  • Gender:Male
  • Location:Tasmania, Australia
  • Interests:Distilling, plough to bottle
    Professional Sand and Ice Sculptor
    repairing water mills
    Making biodiesel

Posted 23 March 2013 - 03:37 PM

With modern TIG welding (or MIG which I haven't used on copper) there is no need to use rivets, if they are used it is for decoration only.

If the joints are soft soldered I would suggest a few rivets as extra safety. Soft solder contains lead so it is not a good choice either.

Rivet heads on the inside of a still will retain moisture when the still is not being used. Copper compounds form in this moisture and you can get quite a buildup of blue/green that can't be good if it gets into the next batch.

A general suggestion for those who have a still that is not being used, open it up and dry it out. I have seen idle, wet stills, mine included, that start dripping blue liquid from the condenser (probably copper sulphate)

#3 Jimmidaboot

Jimmidaboot

    Advanced Member

  • Members
  • PipPipPip
  • 80 posts
  • Gender:Male
  • Location:Olympia, WA

Posted 25 March 2013 - 12:49 PM

The rivets will help to keep the seams together during expansion and contraction, but with a good solidly welded seam, that shouldn't be an issue. You can get lead free solder as well, just keep in mind it is only solder, and as such is a fairly soft metal, so as Pete mentions above, some rivets would be a good safety measure.

#4 Okperioimplant

Okperioimplant

    Newbie

  • Members
  • PipPipPip
  • 36 posts
  • Gender:Male
  • Location:Oklahoma
  • Interests:Spirits, family, learning, copper

Posted 25 March 2013 - 03:45 PM

So most people nowadays, just TIG or MIG weld things, and the rivets are for looks only, with a little retention in there for good measure. How about Brazing a seam? How does that stand up?

#5 clearwaterbrewer

clearwaterbrewer

    Cotherman Distilling

  • Members
  • PipPipPip
  • 64 posts
  • Gender:Male

Posted 25 March 2013 - 07:38 PM

brazing is pretty much silver soldering if you are talking about the same way that HVAC copper is brazed together, and the cost of that silver solder would make a TIG welder purchase really attractive...

#6 Okperioimplant

Okperioimplant

    Newbie

  • Members
  • PipPipPip
  • 36 posts
  • Gender:Male
  • Location:Oklahoma
  • Interests:Spirits, family, learning, copper

Posted 25 March 2013 - 09:33 PM

Going to look into that. Thanks.

#7 Moe

Moe

    Member

  • Members
  • PipPip
  • 11 posts

Posted 26 March 2013 - 06:44 PM

Braziing can be done with a torch using a flux and either brass rod or silicon bronze rod. It can be done with a tig and no flux with each of those rods. The joint does not have to be that tight. HVAC usually uses a phosphous copper rod with no silver in it or maybe a little bit. The phosphous acts as the flux. the tighter the fit the stronger.

Moe

#8 clearwaterbrewer

clearwaterbrewer

    Cotherman Distilling

  • Members
  • PipPipPip
  • 64 posts
  • Gender:Male

Posted 27 March 2013 - 02:12 PM

Here is what HVAC uses, 15% Silver...: $85 for 1lb... http://www.amazon.co...y/dp/B008AE4NBU

This is for copper to copper, brazing steel or other things you can use the other rods... but we are talking copper to copper, just like HVAC.

#9 PeteB

PeteB

    Advanced Member

  • Members
  • PipPipPip
  • 483 posts
  • Gender:Male
  • Location:Tasmania, Australia
  • Interests:Distilling, plough to bottle
    Professional Sand and Ice Sculptor
    repairing water mills
    Making biodiesel

Posted 27 March 2013 - 02:23 PM

Here is what HVAC uses, 15% Silver...: $85 for 1lb... http://www.amazon.co...y/dp/B008AE4NBU

This is for copper to copper, brazing steel or other things you can use the other rods... but we are talking copper to copper, just like HVAC.


Firstly a question, what does HVAC mean?

Also, I assume the above rods are what we call "silver solder". I have mentioned this before, a stillmaker who gave me advice said that silver solder will eventually get holes in it when used in a still.
Does anyone know if this is correct?

#10 Okperioimplant

Okperioimplant

    Newbie

  • Members
  • PipPipPip
  • 36 posts
  • Gender:Male
  • Location:Oklahoma
  • Interests:Spirits, family, learning, copper

Posted 27 March 2013 - 03:14 PM

i dont know for a fact, but silver solder has lower melting point than copper, and stills can get hot. HVAC, is heating, ventilation, and air conditioning. You know AC dudes.

#11 Jimmidaboot

Jimmidaboot

    Advanced Member

  • Members
  • PipPipPip
  • 80 posts
  • Gender:Male
  • Location:Olympia, WA

Posted 28 March 2013 - 03:04 PM

I made a small 25 gallon pot still and heated it with direct fire propane. I used no silver solder, only soft lead free solder. I've run it many times and have never seen it ever get hot enough to melt the soft solder. My max temp ever at the still head has been 208f. I suppose if it were empty it would melt, but who would do that? Melting point of copper is 1,984f. Lead free solder melts at around 425f. Silver solder runs between a melting point of 1250f-1475f, depending on the amount of silver/phos copper. If you get a still that hot, you need to do some more research, or maybe shouldn't be distilling at all.

As far as silver solder getting holes in it, I don't know for certain. I've done many many searches for silver's reactivity with ethanol and have yet to find any info. Anyone?

#12 Moe

Moe

    Member

  • Members
  • PipPip
  • 11 posts

Posted 28 March 2013 - 09:48 PM

Hello Pete

First the term silver solder is used by so many people for such a large number of compositions that it becomes misleading to use the term. Some people refer to the alloy of 95%tin and 5% silver melting about 450F as silver solder or phosph copper which has about 6% phospher 0 to 15% silver the rest copper melt around 1200F to be silver solder others think it must have a min of 40% silver to be called silver solder. Alcohol does not cause pits in silver. Have who ever told you that alcohol causes pits in silver solder to explain what composition he is referring to. I have been working with silver solder making things for over 40 years. I use so much that I just make my own. I like 75% silver 19% copper and 6%zinc. It gives me the ductivity similar to copper so I can hammer curved shapes and anneal at 1400 and not reflow the solder, it is very strong. Now welding technology is so advanced that I Tig weld most copper that is 48 oz or heaver. My tig is a Miller inverter with pulser control.

Moe

#13 PeteB

PeteB

    Advanced Member

  • Members
  • PipPipPip
  • 483 posts
  • Gender:Male
  • Location:Tasmania, Australia
  • Interests:Distilling, plough to bottle
    Professional Sand and Ice Sculptor
    repairing water mills
    Making biodiesel

Posted 28 March 2013 - 10:05 PM

Good information there thanks Moe. The so-called "silver solder" I use for copper water pipes, has only 5% silver.

I will ask for more information about what type of silver solder he claims is pitted by alcohol.





Also tagged with one or more of these keywords: coppersmithing, copper still, rivets, manufacturing of still

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users