Connection suggestion for home made lyne arm

[River Rat]

Hello HD Land,

I'm going to replace the lyne arm on my pot still to eliminate the abrupt size reduction I have now, and to get the output a little further from the flames.
The new one will be a tapered cone going from 2" down to 1/2" over a length of about 2 foot.

I'll either use 2" copper DWV pipe - cut, tapered, and soldered with a lap seam
or
copper sheet cut and formed into a cone. The sheet would allow me to do a locking seam, also soldered.
Any other suggestions are welcome.

My main question: How do folks connect this style arm to the condenser and riser? I do not want to use flour paste. Done that for years and don't want to go back to it.
I'd like to do tri clamp ferrules, but can't imagine a good way to solder them to the arm. It would basically be a butt joint, which I'm not a huge fan of.
If using sheet maybe I could shape the ends to more of a straight "pipe" shape for the ferrules to slip into?

The take-off from the riser is a 2" copper elbow and the liebig has a 1/2" union (could be replaced with a ferrule).
The still is perfectly functional right now so I'm not in a big hurry. I want to do this right.

Thank you all for any input.

[SaltyStaves]

I use stainless steel unions. I can hold the condenser in one hand and tighten/untighten with the other. Tri-clamps and gasket would be a challenge with a 90 degree angle.

My copper lyne arm is tappered. I didn't overlap the seam and brazed it.

[River Rat]

Thanks Salty, sounds like you have already done what I'm wanting to do. I like unions just fine too.
My same question would apply with unions as well. A tapered cone shaped lyne arm won't slide into a ferrule or union, like a straight piece of pipe would. How did you attach your unions to the lyne arm? Just butt it up flat against the end and solder/braze?

[Twisted Brick]

Maybe you could build your tapered lyne arm flattened and soldered to fit inside (or outside) a 3/4" - 1/2" copper reducer? You might even be able to anneal and slightly flare the 3/4" end of the reducer.

[SaltyStaves]

I made a flared collar that slipped into the union and over the end of the lyne arm.
Possibly a bit difficult to see in this photo, but you can see the bump at the end of the lyne arm before the union.

https://homedistiller.org/forum/downloa ... &mode=view

[River Rat]

That's a great solution. Very similar to what Twisted Brick was describing by flaring a reducer. That's a beautiful rig by the way!
Thank you both for the advice.

[cob]

That's a great solution. Very similar to what Twisted Brick was describing by flaring a reducer. That's a beautiful rig by the way!
Thank you both for the advice.

it appears that you have the skill to make a taper from 2" to 1/2". might I suggest stopping the

taper 1" short of the end and making that inch a cylinder appropriate to 1/2" copper pipe.

or similar to twisted's post above solder a stub of pipe in the small end.

FWIW all copper unions are available with only the nut being brass. I have several.

The stainless steel unions mentioned by SaltyStaves are sturdier.

flower paste can be your friend for fussy unions

[River Rat]

might I suggest stopping the

taper 1" short of the end and making that inch a cylinder appropriate to 1/2" copper pipe.

or similar to twisted's post above solder a stub of pipe in the small end.

Yes, another good option. Probably be easier to transition from a cone to a cylinder shape if I use sheet instead of pipe. Sounds like the common theme here is to either shape the end of the cone to fit a piece of pipe or fitting, or, shape a fitting or pipe to fit the cone. Sounds good to me.

My copper lyne arm is tappered. I didn't overlap the seam and brazed it.

This sounds like the way to go. Mating the cone to a pipe or fitting will be much easier if there is no seam (2-4 layers of copper thick).
Time to start studying and practicing brazing. I have an oxy-acetylene torch and some gas welding tips. Got plenty of experience cutting and welding, but have never brazed a thing in my life. Might be time to start!
I'm guessing if the seam doesn't overlap then soft solder would not be a good option, right?

[cob]

Have a look at butterfly keys for butt joint seams. I have a large copper pot and the seams are butt jointed and

soldered with half butterfly keys to prevent separation. I have used butterfly keys in woodworking many times.

when I got that big pot and saw the joinery it was deja vo all over again.

in case you want flat seams instead of lap seams.

[River Rat]

Appreciate it Cob. That's a heck of an idea. I could make them out of the left over scrap once the lyne arm is cut out.
If it doesn't work for some reason I'll try my hand at brazing.

[cob]

the keys don't have to be separate from the lyne arm. if you make one edge

of your butt joint male and the other female, you will not have a loose piece

to fall somewhere when you are trying to monkey f... the seam together.

order 6 more hands off fleabay you could need them.

edit ; the male parts on my BOP are less than 1/2" deep, and 3/4" long along the seam

[River Rat]

Ahh I see now. I was thinking you meant go ahead and solder the butt joint, then solder the butterflies on top straddling the joint. Like scabbing on a reinforcement plate. Yeah I wouldn't try to interlock loose keys until fleabay starts selling extra hands either.

[River Rat]

Well, here is the finished product. Thank you to everybody that offered tips and advice, I took a little bit from everybody's suggestions.
Brazed seam (no overlap), annealed a reducer and shaped it to fit the cone, ferrule on one end and copper union on the other.
Big thanks to SaltyStaves, this will look familiar to you SS. Thank you for sharing the photo of yours.

A quick tip for anybody that reads this and decides to make one. Removing the flaky black oxidation from brazing is easy enough on the outside, but pretty tough on the inside. It's stubborn and really has to be scrubbed away. After fighting with it for a while I ended up filling the lyne arm with number 9 gravel (small gravel with some fines in it) and a little water. It made an abrasive slurry. Capped the ends and shook it back and forth for about 5 minutes. After a good rinse the inside was as shiny and clean as the outside. Ready for a good vinegar run.

[Yummyrum]

Damn thats a nice job . Well done .

[Twisted Brick]

Nicely done, RR! (need more light on the subject to admire your work!)

Curious: what gauge is your copper sheet? And... how'd you flare the reducer after annealing it?

Twisted

[SaltyStaves]

Good job.

Another tip, if you angle the tri-ferrule on the riser, the lyne arm can be set to any angle you like. Mine only has a slight angle and I should have gone for something more exaggerated, like 45 degrees.

[River Rat]

Nicely done, RR! (need more light on the subject to admire your work!)

Curious: what gauge is your copper sheet? And... how'd you flare the reducer after annealing it?

Twisted

Yeah I didn't realize the lighting was so poor until I uploaded the pics to my computer. I used a 10 year old digital camera (on purpose).
It was a piece of 2" DWV pipe. Thicker than any sheet copper I had available but it's still manageable.
I flared the reducer with... don't laugh... an old aluminum baseball bat. It was junk anyway so I cut the end off and it had nearly the perfect taper profile.

[River Rat]

Good job.

Another tip, if you angle the tri-ferrule on the riser, the lyne arm can be set to any angle you like. Mine only has a slight angle and I should have gone for something more exaggerated, like 45 degrees.

You just made my day a whole lot better! I already soldered the ferrule to the riser and I was beating myself up because it ended up a little bit out of square. I hadn't thought about it letting me adjust the angle of the arm. There's a bright side to everything.

Only downside - I was trying to leave myself the option of making a reflux condenser section to clamp in between the riser and lyne arm to make it a CM still in the future. If I decide to get into that kind of thing, and that's a big IF. I suppose since the packed section of column below the condenser would still be perfectly vertical it wouldn't much matter if the condenser and lyne arm had a slight cant.