I agree the gel superglue is the best for surfaces with good contact.

For joining parts by textured sides, I would recommend the original 'Gorilla
glue'.  It expands slightly into the texture and makes a less brittle joint.

Another option is I use a '3d printing pen' as a welding device.  For a
really solid join, if you can get the internal access to the part, make a
grid of holes on the mating surface and 'plug weld' the two parts together
at those points.

You can add a couple of studs to the other side which line up with the holes
for a fantastic alignment - or just a matching hole and put a bolt through
them while you do the other welds.

This is a description of the process in metal but the actions are exactly
the same, I just use a pastel pink '3Doodler' clone!
https://www.mig-welding.co.uk/plug-weld.htm

Cheers,

Alex Gibson

admg consulting

edumaker limited

. Project management
. Operations & Process improvement
. 3D Printing

-----Original Message-----
From: Discuss [mailto:discuss-bounces@lists.openscad.org] On Behalf Of Bryan
Lee
Sent: 19 July 2019 16:25
To: OpenSCAD general discussion
Subject: Re: [OpenSCAD] Joining parts

I was just recommended this:
https://smile.amazon.com/dp/B0778LB4RX

Thus arnholm@arnholm.org hast written on Fri, Jul 19, 2019 at 05:15:13PM
+0200, and, according to prophecy, it shall come to pass that:

OpenSCAD mailing list
Discuss@lists.openscad.org
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

E6000 (labelled as an automotive & industrial) glue was recently recommended to me for PLA. It’s a gel like substance and It comes in a 59ml grey coloured tube and according to the testing conducted by my friend PLA parts will break before the bond does. I’ve not done any testing but I have used it and I’m finding it great. Only downside is that it requires a 24 hr. cure.

To linear_extrude the projection of a linear_extruded shape in a STL file
seems to be a nonsense. You just need to resize its import:

resize([20,20,40])
import("PROFILE20X20_001.stl");

Alternatively, you can generate the profile STL with a unitary height and
scale its import:

scale([1,1,40])
import("PROFILE20X20_001.stl");

Em sex, 19 de jul de 2019 às 08:19, Juan C.Cilleruelo <
juanc.cilleruelo@gmail.com> escreveu:

Yes that is a better way to do it if you know the height of the STL.
Projection is very slow.

On Fri, 19 Jul 2019 at 17:40, Ronaldo Persiano rcmpersiano@gmail.com
wrote:

E6000 seems kind of overkill since it is a specialized epoxy for high
strength joins.  It also looks like it uses a chlorinated solvent so it has
the same health downside as a dichloromethane solvent weld.

nop_head's suggestion of ethyl acetate for a solvent weld (with low health
risk); or standard cyanoacrylate (superglue) or epoxy would probably be
less expensive.

On Fri, Jul 19, 2019 at 12:23 PM Hugo Jackson hugo@apres.net wrote:

E6000 is not an epoxy. It's a tough, flexible, glue.

--
David Gustavson
dbg@SCIzzL.com

On Fri, Jul 19, 2019, at 10:07 AM, Dan Shriver wrote:

This response seems to be, actually, a nonsense.

If I am the creator of the STL and I positioned it, as you can see,
exactly in X = 0, Y = 0 and Z = 0 and plain to Z, I'm almost sure I
don't need to resize it!

scale() and resize() deforms the original figure. linear_extrude only
"EXTRUDE" it.  This is what I want. An extrusion.

Thanks for your response, but it's not an appropriate solution for my
problem.

On 19/07/2019 18:40, Ronaldo Persiano wrote:

So it is kind of hard to be definitive since they want to keep the
composition a trade secret - that being said if you ask google ("What is
e6000 made of") you get this text:

"E6000 is an industrial-strength glue made from a clear drying, flexible
epoxy that works well on wood, metal, glass, ceramics, rubber, vinyl,
leather and (most) plastic. It dries very clear, though can form air
bubbles if you're trying to use it as a sealant."

On Fri, Jul 19, 2019 at 1:23 PM David Gustavson dbg@scizzl.com wrote:

Actually a thick or gel cyanoacrylate glue may be the best glue even for
filling small gaps if you pick the right one.  Cheap superglues don't
perform particularly well, but take a look at the test results below.  This
glue test was done on wood, not PLA, but the CA glue 2P-10 was remarkably
strong even in gap filling.  Much stronger than gorilla glue---in fact, it
was the strongest glue tested in gaps, outperforming even epoxy.

https://www.youtube.com/watch?v=ZoaTZY5cSQE
https://docs.google.com/spreadsheets/d/1GAZrhrtJPi8-iqPRVfqgOgf7RTg8Vqmen6OKJ4Ae6_I/edit#gid=321279609

A problem with gorilla glue is that it expands into gaps by foaming, which
makes it weak.

alexgibson wrote

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Sent from: http://forum.openscad.org/

Other downsides to E6000 are very strong fumes (that persisted for days on a
project where I used a lot) and short shelf life once the tube is opened.
It starts to thicken in the tube and I think becomes difficult to use in a
couple months.

boxcarmib wrote

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