by Russ » Tue May 08, 2018 11:18 pm
Hi all just a quick post with my 2 cents.
First of all thanks to MacStill for the how to make easy flanges, you saved me a bit of cash and I like the idea of soldering copper to copper rather than stainless ferrules to copper.
I have used this method and I found a couple of things I did that helped, but fair warning, I am only in the build process and my flanges haven't been used in anger yet...
First of all I used an angle grinder with a thin blade to cut the 1/4" pipe. What I found is that it was easier to have a piece that just wrapped around the pipe to be flanged (in my case 4") with a bit left over for good measure. The good news about this is anybody doing AC installs will have these lengths by the kilo in their scrap copper bin, asking nicely can get you a surprisingly long way, especially if it is followed with a good story. So the process I used is to wrap the 1/4 pipe around the 4, with a bit extra wrapping around. The 1/4 will tend to spring open again once pressure is released, so I just carefully eased it to a tighter circle by hand away from the 4" until it was a pretty close fit, this is where a single loop helped initially. Once the loop was a pretty good fit with a little clearance, without having to squeeze it together I cut the excess pieces away with the grinder, then checked it on the 4" pipe again, some needed a little more taken off. Once the loop was pretty close I VERY carefully pushed it closed, both sides against a spinning blade, this made the mating surface pretty close to perfect. Now not to brag but I am a tradie so if you are doing this please be careful, if the blade grabs it will launch violently in a direction, most likely towards the nice soft part of your hand between your thumb and fingers, you have been warned. If this concerns you I would think the missus's nail file would do the same job. I didn't have a nail file in the shed at the time so I cannot say for sure.
So once the ring has been made, I just sorta pushed and squeezed it until it sat with both ends together nicely, then silver soldered the join, get the ends to just start glowing red, a small dab of solder, then flip over (carefully...HOT!!!) and draw some more solder with the flame, I didn't need to add much if any more solder to the opposite side, it will follow the heat.
The only other thing to add is I used a lump of 3 by 2 hardwood to hammer the 1/4 pipe onto the 4" pipe. I cut it flat, about 400mm long, and used it as a crude hammer (hitting on the end grain) to flatten the 1/4. As it is flattening it will tend to grip the larger pipe, steady as it goes, don't try to flatten in one pass, rather a couple. I also happen to have a large milling machine in the shed and I used the T slot bed as an anvil, it is very flat and very heavy, but I am sure thick flat steel on something solid would work just as well, copper is pretty soft after all. If the 1/4 happens to pop off the larger pipe once it is mostly flat, it will be almost impossible to get it back on without violence and swearing, and will most likely not be very flat any more, I don't wanna talk about how I know this! Keep checking it by flipping over, use the timber laying across the flange and tap down with a hammer to align.
I found with solver soldering ( I used the yellow tip rods, I think they are 2%) the whole 4" pipe needed to get hot before soldering was any good, so have both flanges done and ready to solder, that will save a lot of gas.
If any of this doesn't make sense, just ask, I don't always explain things very well after a few brandy's, hypothetically speaking of course :)
OK so that wasn't such a quick post.
Cheers.
Russell.
Last edited by
Russ on Tue May 08, 2018 11:19 pm, edited 1 time in total.