Ideas on how to print intersecting tubes ??

Hi,

I'm trying to print some custom pipe joiners, for rain water pipes, but I'm having problems as I need to print at least one of the pipes laying flat (I think)
(see attached PNG)

I want to join a pipe 100mm dia with another rain water pipe 40mm dia (No suitable adaptor seems to be available to buy in my local hardware stores).

I can easily print the 100mm dia pipe, so that in plan view its a circle, however half way up the print, I need to T in a 40mm dia pipe a 90 degrees to the main pipe.

I did an experiment, just printing the 40mm pipe (laid flat on the bed), and overhang was a major problem (when using 1mm wall thickness)

I can add some external support material for the 40mm pipe, and I could add some sort of internal structure lattice structure, as long as water can still flow though.

Does anyone have any clever ideas about how I can accomplish this.

Thanks

Well the obvious thing is just to use the support material feature of your slicer? It just needs a little, Otherwise to make it more printable you can:

1) Flatten the top and hope it stills fits, then bridging can do its work. Of course a requirement to this is that
bridging works well. (It will have to fit more tightly.(rain pipes, not seal-critical? Either way, maybe plumbers tape might be able to seal it somewhat)

2) Make the horizontal pipe slot in using this shape ◊. Or otherwise make it from two parts printed in different orientations, and use some attachment method(yes, that wiki page doesnt exist yet) screw, tie, wire, glue, lock-block it together.(Or use something else)

Thanks Jasper1984,

I'll try using support material, I just wondered if there was any other approach.

I had thought of having less of the 40mm pipe extend from the side, and join on a separate 40mm section, which would be printed separately, but hoped I could avoid this, purely to make the design a bit simpler.

Thanks again

Roger

Hmm i missed an option! Basically take a shape out, which you later insert, and the pipe holds it in. Edit: picture is has the main part upside down as opposed how it is supposed to print, updated the scad.

Edited 1 time(s). Last edit at 10/17/2013 11:14PM by Jasper1984.

Hi Jasper1984,

I've attached my SCAD file - of the original. (I'm an SCAD novice, to apologies in advance for any mistakes in the code ;-)


I see what you mean by adding that extra item, (at the top).

I think I'll try turning on support material (which I've never used before) and if that fails I'll have a go at creating the piece that you suggest in SCAD

Cheers

Roger

The openscad you provided is good. `if(1)` isnt needed; putting an asterisk `*` before a statement makes it disappear. Also unlike in nor'regular'mal programming, global variables can be okey here, anyway, because anyway:

r=10;
module e2()
{   circle(2*r); }
module e1()
{   circle(r); translate([0,2*r]); e2(); }
e1(r=20); //the radius in `e1` is 20, but in `e2` it is 10, you basically have to pass it along.(do `e2(r=r)`) 
//To avoid this, replace the variable `r` with `$r`

Basically the special variable behavior make the global variables act as function arguments a bit.(afaik only Common Lisp had this feature before.) Tbh *I* didnt use this properly before.. using just regular variables.. Hmm the wikibook isnt clear on it, just talking about `$fn`, `$fs`(precision of the model created) afaik.

Note that i have the bad habit of not properly documenting the parameters sometimes.(using really short parameter names is kind-of a choice.) Here, `R` is the big pipe diameter, `r` the small one, `t` 'generally thicknesses used', the rest kindah follows: `d` the distance from the axis the small pipe is held on too. (`eh` extra height for the 'attachment method' `h` the resulting height)

Edited 1 time(s). Last edit at 10/18/2013 09:04AM by Jasper1984.

The slic3r support material generation code works fairly well but it can be a real pain to remove.
What I've found is that using finer layer height (0.1mm instead of 0.3mm, for example) gives me much greater flexibility in handling gentle overhang.

Bridging flat areas doesn't work that well but a domed or arched overhang will often work where a flat area that needs bridging may not work that well.

In your case designing in a single thin support in the middle of your join may help those last few layers and will be much easier to cleanly pare down with a razor knife (as opposed to removing support structure).
Example attached, with the following code added just after your difference() {} block:

// This is just support
translate([0,-(pipe1R+ht),ht])
cube( size=[0.2,ht,pipe2R*2], center=false );

Im quite sure you can buy them, they're call a "strap on boss" or a "soil strap on boss" (oo err!) here in the UK at least!

googled strap on boss

you'll also need a soil boss adaptor, basiacally a rubber doughnut that seals the pipe in I used to work in a builders merchants, and dad was a builder

T0mmmm

Thanks for the info on the commercial product, but I have a load of different pipes that I need to connect, which are often not at right angles to each other, so I'd like to print some custom pipe joiners if possible ;-)

If the pipes join in on the inside (insert into this adapter) then just print it with a square block on the bottom of the 40mm all the way down to the bed so it looks like
_________
|......___......|
|..../........\.....|
|....|\___/|.....|
|__|____|__|

from the side. If you get what I'm talking about.


Oh I see, also at the top would be an issue. Print it flat at the top using bridging and dremel it back to round..?

Edited 1 time(s). Last edit at 10/21/2013 06:33PM by Phizinza.

Jasper1984, I'm assuming your model should be printed upside down from your screen capture orientation? Otherwise it doesn't make much sense to me.