How to make a copper cap seamless and flat

[Krista]

Hello! I want to make a copper flower vase. In my head it is as simple as needing a copper pipe, copper cap and making the seam water tight. My question for you is how do I make where the pipe and cap meet as seem less as in the photo I shared? Most research i'm finding online the copper cap leaves a lip. I cannot figure out how to make it smooth and seamless like the photo. (The photo is not of a vase I only shared it to show the copper work I'm talking about.)

 

[Terry]

The photo shows copper fittings butted up tight. Most likely glued together. There are seams there between the fittings, but snug.

 

[Sponsor]

 

[Reach4]

As Terry said, glue the joints, probably with epoxy. However if you want to solder and not have much if any showing, some ideas come to mind:

If the pipe is big for your vase, apply the solder inside. Or maybe drop some solder indifr, and heat externally. Solder should wick into the fluxed gap but should not climb out on the pipe. Don't flux the part that you don't want the solder to climb into.

For some things there are pre-soldered. With the solder inside, it is less likely the pipe will get much solder outside of the fitting. These are somewhat visually different from what you show.

Viega Propress does not use solder. These are visually different from what you show.

You could find something to resist the solder. Maybe experiment with covering the area to not be soldered with PTFE (Teflon) tape.​

 

[LLigetfa]

Pipe will have a smaller OD than the cap so it will not be flat. The cap is meant to slip over the pipe so the ID of the cap matches the OD of the pipe. To make them both the same OD, you would need to expand the pipe similar to how automotive exhaust pipes are expanded for one to fit in the other.

 

[Jadnashua]

Solder should end up permanent, epoxy may or may not. You could buff any solder off, but you might see a thin line of it where the fittings come together. As Terry said...on that picture, there are three fittings installed over a pipe, all butted together...the cap (and any other fitting) has to be larger than the pipe to slide over it so there's enough room for a decent solder joint rather than a simple butt joint.

 

[Highlander]

Not quite copper but brass railing components could give you that look - part is called “flush end cap”. Probably would work best with matching tubing, not necessarily standard “plumbing” pipe sizes.

http://www.brassrails.com/380.html

 

[hj]

What you need is a "repair sleeve" which has the same o.d. as the cap, but I have never seen them in the larger sizes you are probably looking for.

 

[LikeABigFriedEgg]

I think I am seeing two reducing tees and a cap. Each tee is female on each end, and the cap is female. I expect there is an inch-long section of tubing providing maleness inside each joint to hold the joints together. The joints could be glued or soldered together. If soldered, the outsides of the fittings have been somehow shielded from solder, or the excess solder has been removed from the outside by something like sanding and polishing.

 

[PlumbSolve]

You could use 638 locktite. It will leave you with a very clean joint and will be watertight as well.