6 Week Bubbler Challenge

[Brendan]

For the experienced brazers:

As far as i'm aware, brazing/silver soldering only really works where there is no gap (ie. a few thou). With my sight glass ports, certain parts around the scallop that attaches to the column are a perfect touching seam, and some parts on sides have a larger gap (where you can see light through), but where I consider them soft solderable.

I'm thinking maybe I can silver solder the parts that are very close for strength...and then solder the entire seam with soft solder to fill the gaps. I have a couple of concerns here...

Cleaning the join after the silver soldering, in preparation for the soft soldering will be difficult. Will get it back shiny, but will need it nice and clean where i can fit wet & dry paper in to be well prepped for soft solder to flow around the entire join.

Also, the easy flanges at the ends of my modules are soft soldered around to hold the flattened 1/4' ring on...i'm concerned about trying to get the temp of that sight glass port to temp for silver soldering (700-800 deg C) onto the column, without melting the soft solder at each end. I will apply lots of heat sinks (metal clamps), and may even leave the column connected with tri clamps to take away any heat working along the piece, and just try to concentrate the heat hard and fast with the MAP torch on the port seam :doh: The modules are 145mm high.

[MacStill]

Red Eyes

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:obscene-birdiedoublered:

[kelbygreen]

just soft solder I have filled 2mm gaps with no leaks on my liebig as I got 1' and a 1/4 and the 1" reducers I got was so sloppy inside it. I just filled it up and it worked lol

Cant see why the ports would need brazing. As mac said you will prob bend the cooper before the soft solder lets go.

[Kimbo]

Red eyes

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[tickle]

Brendan, I use 15 percent hard solder when ever I have a large gap to fill. With a little practice you will be able to "build up" a suprizing amount. Get it hot enough for the rod to stick to the copper, and gradually pull the flame back so you are only melting the rod to what you've already melted. Takes practice, but bridging gaps of 1/2mm are easy once you get the hang of it. Its easier than most of what you've already accomplished on this build!

[bt1]

+1,

Use 2.5% silver to specifically fill gaps. With some practice it can span a fare way. The last lot of downcomers I did where a good example about 4 mm as tacks only.

I've not been able to get soft solder to ever fill like it can be done with braze.

bt1

[emptyglass]

"Silicone Sally"?

"Implant Grant"?

Nice job by the way Brendan.
If you can improve the fit up before you start soldering, you should just be able to soft solder it. If you do choose to hard solder it (don't use brazing/bronze solder, too hot!, use silver) you might need to wrap the soft soldered flanges with a wet rag if they are close to the sightglass area. Keep the rag wet, if it starts to smoulder, you're getting heat where you wont want it

[Brendan]

Thanks guys.

I have both 15% silver, and 2.5% silver...so not too sure yet. I'd prefer to work with the 15%, but I have a few gaps greater than 1/2mm (not many though)...prob more like 1 to 1.5mm.

Although soft soldering is strong enough for our application, I have seen a few 90 deg joins like this (pipe edge to pipe wall) crack and break...I want this to be very strong and live forever :-D

Tickle, I know what you mean about the point where the rod sticks on :handgestures-thumbupleft:

[bt1]

Howdy,

If I recall it right the higher the Silver content the hotter it has to be...like big lumps of 0c difference...trying to find the ref page at the mo.

2.5% has this nice semi liquid phase where it can be poked, moved and stretched into place..kinda pre flow...it really is fun to play with it on test pieces till your ok with it. Someone mentioned its kinda sticky on hot copper...that's true you can shape it...

here's a picy of downcomer mentioned it's really is about 4mm gaps...

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[tickle]

Brendan,
i'm not trying to pass myself off as an expert in any way. either the 15% or the 2.5% should work. I use 15% because its common around here in the hvac industry, flows nice, and is strong. I seldom use the 2.5, because its not really stocked locally; but like BT said, its good stuff. You wont have any problems filling those small gaps with either.

tick tock....make some magic! :handgestures-thumbupleft:

[emptyglass]

Brendan,
i'm not trying to pass myself off as an expert in any way. either the 15% or the 2.5% should work. I use 15% because its common around here in the hvac industry, flows nice, and is strong. I seldom use the 2.5, because its not really stocked locally; but like BT said, its good stuff. You wont have any problems filling those small gaps with either.

tick tock....make some magic! :handgestures-thumbupleft:

Mate, if you get it to stick, you're an expert!

[bt1]

tickle,

if I was in US I'd use 15% I reckon cos its the norm...just Aussies are cheap bastards in some respects so 2.5% is the norm.

Like our 2"/50mm pipe is 2"/50mm OD where yours is ID...know this cos bought in some keg adapters early days...

F*&^ I said I then had to silver solder the bloody huge gaps up...PITA kiss good bye to $50, 2Lt to a mate for oxy use and half a morning on that little experiment.

bt1

[Brendan]

Okay time for a bit of an update...this prob won't be too interesting as most have seen it all before, but keeping in the spirit of this thread i'm putting up lots of pics :handgestures-thumbupleft:

Only one week to go, so coming into the home stretch. Unfortunately we're away for a few days for a family funeral, but you can't foresee these things :sad: Although it may look a long way off I have a lot planned later this week, so hopefully can bring it home at the finish line :D

I marked out all 6 of my perforated plates (1.59mm holes (1/16"), on 5mm grid), as well as the end plates for the reflux condenser (3" with 4x 1/2" inner tubes).

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Started cutting out the holes...the ones on the left aren't done as I was trialling my cutting method to see how well it worked before going ahead. Only had a 20mm holesaw, so used that and used the dremel and file to get the rest of the way.

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Pretty bloody good fit if you ask me :handgestures-thumbupleft:

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[Brendan]

Bit of a mock-up...

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[MacStill]

Looking great champ :handgestures-thumbupleft:

I think under the circumstances the forum will grant you an extra few days to complete it, don't rush it mate ;-)

[Brendan]

Got my first perforated plate drilled...

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After 3 weeks of hammering until my arms fell off...here is the bain of my existence...

It's finally plumb/straight!! :happy-partydance: I thought it was at first however I was only checking the level where the plates sit, however when looking from the side, even by eye I could notice a big curve up the side. This had to be the absolute worst part of this build...if you want to make a modular bubbler completely out of easy flanges, be prepared to become one with your hammer :angry-banghead:

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The plate is not flat anymore as you can see from all the center punches, but i'll have that flattened back out after I do the other 5 8-}

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And after lots of trial and error and plenty of leak testing, my sight glasses are all ready to be attached to the column :geek:

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Ooh I hope she lives up to her name! :dance:

[emptyglass]

Looking great champ :handgestures-thumbupleft:

I think under the circumstances the forum will grant you an extra few days to complete it, don't rush it mate ;-)

For sure. If you rush it, you will regret it. Ether way, we will find something to pick on, :teasing-tease: :teasing-tease:
Your doing well mate. If you rush it, it will only mean your 8 year old scotch will be ready a few days earlier.

[Brendan]

Ahh but an 8 year old Scotch is only aged that long because its so rough out of the still. Hopefully with this baby, a year or two will suffice ;-)

Thanks guys, can't say I rush anything...if I get time, it gets done :!!

[Linny]

Well done mate :handgestures-thumbupleft:

[Brendan]

Thanks mate

Can't wait to get into it later this week :D