3D Printing: How to connect filament end-to-end? (3 Solutions!!)
Channel: Roel Van de Paar
Date: 2019-06-29

3D Printing: How to connect filament end-to-end?


The Question: Is it possible to connect two pieces of 1.75 mm filament end to end, with no
change in width? I am asking the question because I am interested in creating a
multi-filament feeder to a single extruder, and I am curious about the process
of changing filament while the 3-d printer extruder continues uninterrupted. My
current best-guess at the optimal solution is to someone 'cut' one end of the
filament and 'melt' it to the end of another filament.

Solutions: Please watch the whole video to see all solutions, in order of how many people found them helpful

== This solution helped 5 people ==
You'd have to ensure that the joining portion of the two filaments do not
"bloom" or increase in diameter, which would happen if unconstrained at the
melting and joining time. Alignment is also critical, otherwise you have a
varying diameter from one color to the next at the point of join.
There's an item on ebay which is precision drilled and has precision machined
mating surfaces to ensure alignment of the filament. The filament is extended
through the two components, heated (in the case of the video, with a match) and
the two metal parts are pushed together. The joining of the metal parts also
cuts away the excess bulge of the melted filament, ensuring correct diameter.
In the case of the above item, the joining devices have to be threaded with the
filament prior to the joining process and then have to be threaded off the
filament by pushing them the entire length of the filament.
This would be okay if one were joining short lengths only. Consider how much
fun it isn't to have to slide these two pieces over an entire full spool of
filament.
A split device which would enable one to un-latch or otherwise open a clamshell
to release the filament would require much more challenging machining to
achieve the necessary precision, which is probably why we don't see such a
product.

== This solution helped 3 people ==
There is a device which can do what fred_dot_u describes in his otherwise
explanatorily good answer: the www.i3dinno.com/easywelder-en-
p186486.html, made by I3D Inno.
It fixes the filament in a separate part so that the faces are adjoined
perpendicularly and then heats the joint electrically with a device that at
first sight reminds me of a hair straightening iron.
I am not sure about the joint quality this machine produces, but I am skeptical
whether the it is good enough for high accuracy 3d printing. Especially if you
take the history of the device into account (he wanted to create a custom O-
ring from Ninjaflex), which the inventor shortly describes on this
instructable: www.instructables.com/id/Welding-tool-for-plastic-
filaments

With thanks & praise to God, and with thanks to the many people who have made this project possible! | Content (except music & images) licensed under cc by-sa 3.0 | Music: www.bensound.com/royalty-free-music | Images: stocksnap.io/license & others | With thanks to user Starlino (askubuntu.com/users/7787), user starlino (askubuntu.com/users/7786), user kamuro (askubuntu.com/users/168), user J. Roibal - BlockchainEng (askubuntu.com/users/2111), user fred_dot_u (askubuntu.com/users/854), and the Stack Exchange Network (3dprinting.stackexchange.com/questions/1345). Trademarks are property of their respective owners. Disclaimer: All information is provided "AS IS" without warranty of any kind. You are responsible for your own actions. Please contact me if anything is amiss at Roel D.OT VandePaar A.T gmail.com.