Helping a friend with a craft project. It involves bringing 8 pieces of PEX tubing together into a hub, all in the same plane and equally spaced at 45°. I need ideas how to connect 8 ends of PEX together.

I made a prototype from a piece of oak by cutting it into an octagon and then drilling a hole in each face. The hole diameter matches the 5/8" OD of the PEX.

This prototype works well but I'm looking for something:
1) easier to make - she needs at least 10 hubs, and that would be a lot of miter cuts and 80 drilled holes, ie. a pain
2) more stable against the elements - this is for an outdoor display, the oak may be OK if I treat it with anti-rot, which I have
3) more elegant - the wooden block still looks...blocky.

I'd prefer an 8 pointed star that I could slip the PEX over, instead of a block to slip the PEX into. The ID of the PEX is between 7/16" and 1/2". I think you could heat the PEX and slide it onto 1/2" with some effort.

They sell hose-barbed tubing fittings in a cross, and I've considered mounting 2 together at 45° to each other to get 8 ends together. They wouldn't be in the same plane but it might be close enough. Trouble is, these things aren't cheap and they're not locally available.

I've thought of using pieces of threaded rod welded to a flat washer, but I have no welding tools or experience.

Thinking caps on?

 

hi w,
Have you considered using a PEX pipe with a larger diameter, cutting a short section off one end and drilling 8 holes in its periphery and inserting the 8 tubes in the holes and then hot melt adhesive.
A short length of house PVC guttering down pipe could be a cheaper option.

E
If the centre of the hub has to be on say a spindle push in the smaller PEX tubes until they meet in the centre.

 

I have considered PVC instead of wood. Great durability, but I'd still have to drill a lot of holes. And I need at least about an inch of solid contact to hold the PEX in plane.

FWIW, the hub I've made so far resembles a Tinkertoy hub. Or here. I don't need any central axis.

 

I have considered PVC instead of wood. Great durability, but I'd still have to drill a lot of holes. And I need at least about an inch of solid contact to hold the PEX in plane.

FWIW, the hub I've made so far resembles a Tinkertoy hub. Or here. I don't need any central axis.

So, it's just sculpture? it's not functional as a water supply sculpture? If you used the spider tubes for Swamp Coolers many have 8 tubes and they would allow for water flow?

Don't know what your after but; looks like a fun project.

http://www.amazon.com/LASCO-05-1153-Evaporative-Cooler-Spider/dp/B00HYWDLT4

 

Does she want the rigidity of a fitting or wood? If she is ok with flexible, then you could use copper wire. Pound 16 nails into a board smaller octagon inside of a larger octagon (offset by 22 degrees). Weave the copper between the nails so you have 8 lobes that can inset into the PVC about an inch (pull the woven copper off of your nail template). Then drill a hole 3/4" from the end of each PVC and use a second piece of copper wire or other weather -resistant lace through the hole to catch each lobe.

Use some solid 10 gauge wire and a deeper lobe (4") if she wants something that holds shape better. Use a shorter lobe and insulated stranded copper if she wants more flexible.

 

The rigidity is important, and there is no water flow involved. Dry sculpture. Two hubs hold the tubing ends to form a sphere. Picture 4 interlocked hula hoops, with the hubs joining them all together at opposites poles.

 

If you used the spider tubes for Swamp Coolers many have 8 tubes and they would allow for water flow?

Nice idea. That 8-tube spider looks like it could be perfect if I can find one that's the right size. So far it looks like the only one available if for a tubing OD of 3/8", and my PEX is 5/8".

 

Nice idea. That 8-tube spider looks like it could be perfect if I can find one that's the right size. So far it looks like the only one available if for a tubing OD of 3/8", and my PEX is 5/8".

Try to find an adaptor to size it up.

kv

 

hi wayneh.
Have you considered making a 'holding frame' for the 8 rods, with a simple hub mould that could be filled with a clear acrylic two part epoxy mix.?
The holding frame would only be used to keep the rods steady while the epoxy cures.
The hub mould could be either a disposable or re-usable design.

E

 

Yes, I have thought of that, although I was thinking of using mortar because I have a pail of it in my workshop.

I more or less ruled it out because making my wooden hub is probably easier than casting a mold. The idea of clear acrylic is appealing, though. I'll think about this some more.

 

I might look at 2 round discs and sandwiching the ends between them..
You could just drill some bolt holes around the disc to locate the pieces and clamp it all together with.

 

how is your Plumbing soldering skills?
you could find the right size copper plumbing pipe, then cut to length, then solder them to a vertical piece, you would have to file the ends to fit the rounded middle piece(you could even use a bigger diameter piece for center, if you don't know how to solder, its not that hard, standard length of a piece of 1/2 inch copper pipe is 8' (they sell 10' also) so you would have plenty of extra to practice on, the trick is to clean the ends with sandpaper, flux it up, then heat it with a propane torch till the metal is hot enough to melt solder, solder will flow towards the heat, so when you get proficient with soldering, you can utilize this to create..

<edit> here is a good link i found on how to.
http://www.familyhandyman.com/plumbing/how-to-solder-copper-pipe/view-all

 

or you can get something like this,

this is a copper pex distribution node, its copper so it bends easy, with the proper tool, you could bend it into a circle (the tool would be too expensive i think,) personally i would ask a plumber if he could help bend it, but im not you..
this is made for pex, so there would be no worry about it fitting.

 

I'm pretty handy with sweating pipe, and I thought about how I might make a hub that way. I think it would be more work than making one out of wood, but with the advantage of being nicer once it was done.

Bending a manifold into a circle never occurred to me. I wonder how practical that is?

 

I'm pretty handy with sweating pipe, and I thought about how I might make a hub that way. I think it would be more work than making one out of wood, but with the advantage of being nicer once it was done.

Bending a manifold into a circle never occurred to me. I wonder how practical that is?

since when does art stop at 'more work'?..(and stronger than wood)
and ask a plumber about the bending, I am contractor (retired) so I really have never bent pipe..
something like this is what I am thinking, the center is just a vertical pipe..

 

3D printing?

 

One limiting factor here is cost, so 3D is out, and I imagine casting acrylic is probably out as well, although I haven't researched casting resin. I just know when I was looking for potting options in the past, none were cheap except for fiberglass resin. Bondo might be an option for this project.

Even copper plumbing fittings are probably out on cost. I considered cutting short sections from a length of copper pipe, but that quickly adds up to more work and cost than the wood block approach.

Another thing I've considered is a ~3" steel ring at each pole of the sphere. These rings have a latch and hinge that allows it to be opened and they are available in hardware stores. The PEX tubes would have to be drilled and threaded onto the rings like keys. Drawing the two rings together might force the tubes into a sphere. Something would be needed to space the tubes evenly at 45° intervals, but I could solve that with a band around the equator.

Here's the current prototype using cheap hula hoops instead of PEX. The wood is 3-1/4" wide and 1" thick. The drilled holes are all 5/8" to match the OD of the PEX.

 

I'm pretty handy with sweating pipe, and I thought about how I might make a hub that way. I think it would be more work than making one out of wood, but with the advantage of being nicer once it was done.

Bending a manifold into a circle never occurred to me. I wonder how practical that is?

Fill it with sand; heat it and shape. Cut the ends and remove the sand.

kv

Edit: I would stick with copper and avoid the pex. Then just solder 1/4 or 3/8" from there into any shapes you want.
Once it's oxidized it will look pretty cool. Once again you can shoot water through it. lol

e.g. Add some misting heads to complete the water art project.

 

If it was me, I'd use copper for the looks and other advantages. But my friend wants it super cheap. She plans to paint the structure to resemble some metal. Not my problem.

 

If it was me, I'd use copper for the looks and other advantages. But my friend wants it super cheap. She plans to paint the structure to resemble some metal. Not my problem.

copper pipe is pretty cheap, and it you want cheaper look/ask around for a home demolition project that you could snag some pipe for free..