Soldering multiple copper bits needs multiple arms???

[jonnys_spirit]

Nice POC Yummy! Is that MAP?

Cheers,
j

[Yummyrum]

Yes jonny
Most disgusting piece of brazing I have ever done , but the pipes were too close together and I was using a really fat rod .

[quadra]

It is a thing of beauty! Nice work yummer

[quadra]

My father is a highly respected scientist, published author, and patent holder. He is also so stubborn, arrogant, and dazzled by his own brilliance that he often cannot see and cannot be told how boneheaded he is being. Whether that is merely a personal anecdote or applicable to anyone here (myself included) I leave as an exercise for the reader.

It seems to me that you are trying to reinvent the wheel. If the goal is to form a 180 degree return in copper pipe, there are commercially available fittings which do just that. If the radius is too broad and the resulting spacing too wide, a street elbow and standard elbow could be trimmed to allow minimal (say, 1mm) overlap and still be far easier to assemble and solder than the design you propose. It may be that you have some specific reason for needing something which is impossible with any commercial fittings, but it might be worth a look at the range of options available before going down the 100% custom route.

Interesting. I find it sad that you have such a low opinion of your father.

My late father was a gifted craftsman, not educated to a high degree academically, but respected for his skill-set and patience. He went out of his way to offer encouragement and explain his own thoughts in complimentary fashion rather than "holier than thou". He realised that learning was a gradual thing and open-mindedness to new things and approaches is always a key element of Progress.

Some feel that they must impose their own ideas, their own methods and even solutions onto others, without full knowledge of why a particular research and experiment route was chosen. They often yield to the temptation of misdirection from a Topic's subject matter too.
Maybe they feel that they have an obligation to direct others as they see fit? And expect obedience to all of their commands, however impertinent!
........Or maybe "like father like son" applies very strongly in their negative case.
Generally, obvious "smarminess" applies to their behaviour [see Google, UK terminology].

Whether that is merely a personal anecdote or applicable to anyone here (myself included), I also leave as an exercise for the reader.


Criticism or suggestions regarding my disclosed projects is perfectly acceptable and welcomed.
For those who don't like my experimentation or the approach I take, by all means offer alternatives and explanations but please find something to do other than to criticise my person. Directly or otherwise!
I have been known to bite back.

I don't think we need to Google smarminess. Multiple excellent options and demonstrations have been provided, please post pictures of your progress.

[MooseMan]

Sometimes you just have to get in the shed and try something .
Sorry no milling machines or lathes , so the fit is not perfect and I made the coupling too short .best I could do with a drill and a file

The point of the exercise was to see how hard it was to hold it all together while brazing .
Turns out the wire twitch method works perfectly and I even accidentally dropped it on the floor and it stayed together .

Alas because the gap between the pipes was too close , the brazing rod started to flow between the pipes .

IMG_1677.jpegIMG_1678.jpegIMG_1679.jpegIMG_1680.jpeg

Well, that worked a treat!
You ain't gonna get much better than that as solutions go, so let's hope BC gives it a crack and posts photos of the successful job!

Nice yummy.

[Saltbush Bill]

Octoyummy.

[Yummyrum]

After my feeble attempt in the shed yesterday to find a solution to the holding while soldering problem , it occurred to me that the bigger question is how do you easily make the little coupling piece ?
I found that really challenging

[Saltbush Bill]

Yummy I'd do them the same way you shape 2 or 3 inch sight glass mounts for a plated column, rough out the curve needed then finish it off to a perfect fit using wet and dry / emery paper wrapped around a piece of copper pipe of the correct size.
With pipe that small you might even be able to drill a tiny pilot hole through the pipe then increase the hole size to slightly smaller than finished size, then cut at half way mark, finish on emery paper as above. This might give you two ends for two pieces, done the right way.
I think you will get what I mean, just a tiny version of the same thing.
I'll try and find a better photo if I can.

Edit , found photo, Rub part needing to fit this way once roughed out.
Note abrasive paper around copper pipe........should take no time at all on pissy little pipe like OP is using. Photo is 3
inch on 6

mount 03.jpg (15.92 KiB) Viewed 1433 times

[MooseMan]

I'd clamp the pipe between sacrificial bits of wood, mark out the width needed and in a pillar drill, using a drill bit the same diameter as the pipe, drill either side of the markouts.
Tiny bit of cleaning up after the drill, done.

[Saltbush Bill]

About what I was suggesting with drill Moose , just you worded it better, clean up and chamfer edges using abrasive paper as last step in shaping process after drilling.

[Yummyrum]

For full disclosure , I did try increasing size drill bits but as I got close ti the full diameter , it would grab and tear .

In the end I used a pilot hole and a rounded burr bit ( I think that’s its name) to drill through the tube . Then the second hole .

Interestingly the copper wanted to expand outwards ( bulge ) as the drill got close to the middle

I think that is where Mooses idea of a wooden clamp to hold it would be beneficial .

Salty ,I know that sandpaper technique very well from my sight-glass making days .

Thought about it but didn’t try it . As the coupler is the same diameter as the main pipes , the sand paper thickness becomes an issue . Probably should have tried it on the shaft of a smaller size drill bit . ….. that would have worked

One major issue however was heat . Drilling , sanding , fileing copper heats it up big time . I could not hold that little piece fir long before my fingers burned . Ended up holding it with some pliers while filing to save my pinkys .

[NZChris]

You're trying to make something without knowing the reason for it. Does the link have to be round? It might if it's maze game for a rat, but if it's for liquid or vapor it could be any convenient shape. A rectangle would be easier and could be cut out of sheet.

[Yummyrum]

Agree on both accounts Chris .
Seems OP is holding the whole thing close to his chest and unlikely to ever say if bother to reply . So we are just having some fun .

[BritishChemist]

Sorry folks, been away a few days on family stuff, but back here now for a couple of days .
Here's my latest experimentation:
I support the two (diagonally cut) copper pipes with an INTERNAL jig made from a bit of titanium tube which is also cut diagonally. You can't see the internal bit running horizontally because it's hidden inside it's section of copper.....

There's no need to worry about the visible gaps in the copper (the simple but roughly-made pipe cutting jig will be refined to close that up).
For testing, I just wind a bit of fine, clean copper wire around the gap so that capillary action can work when I apply the silver solder/braze and bingo - we'll have a joined tube at right angles.
Note that silver solder or even copper/phosphorus braze won't stick to titanium (there's a strong metal resist oxide / nitride coating on titanium).
Once the silver soldering is done, I'll just untie the bolts holding the titanium tube jig together and pull the two pieces out of the workpiece.
High confidence that will do the trick!
Issue:
I found a Chinese source of very cheap 15mm copper elbows!! Around 50 cents each.
So now that I've had my experimentation fun, I might revert to the standard use of ready-made copper elbow joints......

Hope you're all finding the chemistry of this interesting and that it might inspire a new way to keep braze or silver solder in the place where you want it to be and away from where it mustn't go? Lots of sorts of titanium on EBay etc. these days; rod, wire, plate etc. and bear in mind that a little bit goes a long way when used this way.

You can also have huge fun (if you're that way inclined) by making jewellery rings out of Ti pipe and then anodising it at different voltages to generate an oxide layer of specific thickness (measured in nanometers BTW!). This gives the surface a specific colour due to selective surface refraction. The ladies find them highly attractive too.......

Do a bit of Googling to see about that.
Lots of videos on it!
More news when I generate it!

[BritishChemist]

Oh yes, I got hold of some 0.05mm copper foil and that DOES spot weld (just about) with those cheap microspot welders!
Using such foil might be a handy way to wrap a leaky/cracked pipe and hold it in place - especially if you then wrap the foiled section with stout-ish copper wire and braze that to add thickness/strength?
Just a bit more "outside the 9 dots" thinking........

[OtisT]

Hi Chemist. I’m having a hard time wrapping my brain around your comment that “it DOES work (just about)”. That sounds like a fail to me. I personally have had multiple failed attempts making various pieces of distillation equipment, so your not alone there. We learn a lot from our mistakes.

I think your making a good choice by going with elbows. I don’t think that gig would work beyond the first joint. Keep on keeping on. Otis

[shadylane]

A readily available factory 90' will also flow better than a miter cut and soldered joint.
Some times it's easier to buy a wheel than it is to reinvent one and build it.

[BritishChemist]

Hi Chemist. I’m having a hard time wrapping my brain around your comment that “it DOES work (just about)”. That sounds like a fail to me. I personally have had multiple failed attempts making various pieces of distillation equipment, so your not alone there. We learn a lot from our mistakes.

I think your making a good choice by going with elbows. I don’t think that gig would work beyond the first joint. Keep on keeping on. Otis

Hi Otis.
Standard elbows do now provide me with most design/development flexibility. They do engender some spacial limitations though (which I have a workaround for now!)
I will go with ready-made 15mm copper elbows at least on my prototype item because it saves a lot of time and patience.
That said, I now feel very much on top of creating strong mitred joints easily, accurately and very cheaply should I need lots of them!

I hope any Reader facing particular spatial issues (such as the need to fold pipework back on itself through 270 degrees, zig-zag fashion) will benefit from what I shared. Pipes may even almost touch the pipe above and the one below - and as far as I can see, that can only be done with the mitred joint method......! Not for any item build that I have seen but maybe one will come up where an elbow will not do the job spatially?......
My initial need to squeeze as many rows of pipe as I can, vertically, led to the experimentation.
The thought process involved has led me to several item design improvements (and cost reductions!)
Which is for me the major fun element!!!
Enjoy!

[shadylane]

Plan B
Don't use any fittings, anneal and bend the tubing.

[BritishChemist]

Plan B
Don't use any fittings, anneal and bend the tubing.

That's OK for a right angle bend as long as one is not too bothered about the radius of the bend itself.
I do that whenever I need one. Elbows have a much tighter radius than is achievable with a standard 15mm pipe bender though.

To get a 270 degree bend with the pipe "turning back on itself" and parallel, with just a 10mm gap between them ?
Such a bend is beyond the malleability of even annealed copper; the outside radius for 15mm pipe would be only a little more than 15mm......

Unless of course you can illustrate a trick or two to make it happen?
I would genuinely be hugely interested in being able to do that!!!!

[GrumbleStill]

270 - RU sure it’s not 180?

[BritishChemist]

270 - RU sure it’s not 180?

Hi GrumbleStill, happy to give you a chuckle!
You passed the test (seeing that I get confused on angles sometimes!)

Yes, it's 180°.... just me thinking that -90° (backwards) is +270°when looking at an UPRIGHT pipe in my CAD setup!
But of course upright on my CAD setup is 0°
☼

[shadylane]

Maybe use a mixture of regular female short radius elbows and "Copper FTG X C Short Radius Street 90-Degree Elbows"
Notice the fitting is male on 1 end and female on the other.
A little bit of mods such as shortening the mating area on the combination would make a fast 180'

[BritishChemist]

Maybe use a mixture of regular female short radius elbows and "Copper FTG X C Short Radius Street 90-Degree Elbows"
Notice the fitting is male on 1 end and female on the other.
A little bit of mods such as shortening the mating area on the combination would make a fast 180'

The elbows I got (as a job lot for 50 cents each!) are female on both ends, so using a short piece of pipe as a connector gives a 180° turn with a gap between the parallel pipes of 20mm. Not ideal, but I can work around that....

For now, I'm going ahead with what I have and finishing the design of other bits that are part of the parent project. No doubt there will be other things to stymie me as almost all of the project is very radical and "breaking new ground".

I can't share details of the overall project, at least at this stage. It's ownership is shared........ but with luck, it will make a great "reveal" essay at some stage!!!!
☼☼

[shadylane]

I decided to test my own advice using 1/2" ID fittings
The top pic is the fittings asis and then I shorted them and finally stuck the two together.
With the amount ground off the fittings, the spacing between tubes installed in them was 9.2 MM.

[BritishChemist]

I decided to test my own advice using 1/2" ID fittings
The top pic is the fittings asis and then I shorted them and finally stuck the two together.
With the amount ground off the fittings, the spacing between tubes installed in them was 9.2 MM.

Neat.
Such a pity that mine are female + female, because I can see that if one end was male, with a bit of grinding I could get down to 10mm or a shade less too!
We're clearly tuned into the same "ways and means" wavelength so thanks for sharing your craftiness!!!
By grinding the female orifices down from 10mm long to 5mm long, I can get mine down to a pipe gap of 15mm by following your "shorten it" lead, and I can make that work.
Have a great weekend!
☼☼☼