Playing around with filament welding again

[jsc]

Another trial in my on again, off again quest to make filament joining easier:

I designed a pair of pliers with removable clamps to hold the filament to be joined. In theory, it should help keep the ends in alignment as they are joined:

joiner.jpg (100.69 KiB) Viewed 14701 times

Resulting weld, made by clamping on a quarter heated on the stove to melt the ends:

joined.jpg (92 KiB) Viewed 14701 times

On the positive side, the joint is very strong. I cannot pull it apart.

On the less than good side, it would have to be cleaned up manually before it would feed, and the alignment was not as good as I was hoping for, although some tweaking might help there. Also, playing around with blazing hot quarters is not a safe hobby. I do have a temperature controlled soldering iron, which I am reluctant to gunk up. I also considered using a hot extruder nozzle, but that is a bit cumbersome.

Really, you'd want something done in metal, and not something made out of the same plastic you're exposing to welding temperatures. Anyone with a mill want to have a go?

[Jules]

Cool looking pliers!

[Matt_Sharkey]

as a feature to your pliers,

A 1.8mm Through hole, countersunk large enough to hold the blob.
A slot to hold a standard flat razor, tangent to the 1.8mm hole (at an angle to help start the cutting)

pull the filament through and jam the blob into the countersink, roll the filament around to cut the blob off.

also you could design this into it's own pliers so that you can clamp it around the filament, instead of feeding it because in a real scenario, you won't have access to either end of filament to feed it through.


If you get rich off of this idea, I demand 5% royalties :p

[innkeeper]

Also, playing around with blazing hot quarters is not a safe hobby.

hmm why not.. like the rest of what we do is safe and healthy working with molten hot plastic, coming from open framed machines with high torque motors with open drive belts, and exposed heated surfaces of 230c which we routinely stick our hands into with pair of tweezers to get that little string of plastic out that is annoying us while operating. while all the time breathing in the fumes of molten plastic with unknown health hazards.

remind me to take up skydiving.

[Alloy]

Has anyone tried an ultrasonic welder?

[Jules]

Chuckle! This group is so much fun!

Don't know if this will help or not, (probably not, since that crappo little hair curling iron i picked up for $10 from Amazon was a complete bust at melting the ends together), but since you've now got a cool little pliers to hold the ends together safely, maybe you could just heat the metal end of a pair of bead crimping pliers with a Bic and then wrap them around the filament join for a couple of seconds.

Might work, might not.

[innkeeper]

Has anyone tried an ultrasonic welder?

i looked into one...damn they are expensive... id give it a try if i could pick up one cheap.

[jsc]

Yeah, I would love to try ultrasonic welding. But just the horns alone cost mucho dinero, let alone the machines they go into. This guy has some DIY experiments listed where he used the element from an ultrasonic cleaner, which is no longer sold: http://www.thingiverse.com/thing:297380/#instructions

I think the key is to have the melting happening in a closed environment, which is difficult to do without metal parts.

Jules, I just looked up bead crimping pliers, didn't even know such things existed, thanks. Maybe one for 2mm beads would work....

[Jules]

What might work even better than the crimpers (since those might make a thin spot at the join), is a really cheap pair of electrical stripping pliers.

http://www.amazon.com/Multifunction-Ele ... ing+pliers

(I'm finding all kinds of cool tools to buy today. )

Update: No, nope, no good, nada.....these are not the right tool for the job - go with the bead crimpers instead.

[werner]

have a look at this.
http://zurich.fablab.ch/pla-splicer
greatings from Switzerland
werner