Found this interesting article on Hackaday. Dude managed to turn a high-temp glue gun, into a PLA-gun. It required modeling the PLA glue sticks a specific way so that the latch could catch and push them into the machine, but in the end it turned out to work pretty well. This is probably a good option where one of those dinky “3D pens” won’t work for welding material together.
I kind of feel like upping the temperature on this thing would help improve the flow and bonding characteristics, but at the same time, when getting into the 240C range, PLA starts to not only liquefy but break down into a horrible black gooey mess.
Correction to the OP statement: the stick’s shape primary function is to work as a plunge, as otherwise the melted plastic will leak up instead of flowing down the hot end.
@Whosa_whatsis Nice article. I’ve had the same experience with the fast drying HDX super glue. It set up before I could get the parts all the way together even with locator pins. The working area needs to be really small. I’ve used the loctite before and found it to be quite strong. Krazy glue (another cyanoacrylate) works really well for me. Locator pins are a must for any of these. For larger assemblies I use the brown Gorilla glue. The Gorilla glue needs to be clamped, does expand (fills crevices), and takes a long time to fully cure but it makes a very strong bond.
Oh, and to apply the Gorilla glue to hard to reach places I put some on a strip of tin foil folded over several times and just rub it on the surfaces to be bonded. If they are already wet with water it spreads quite nicely.
@Alex_Koukarine the primary issue here was not the plunging bit of the PLA, but the fact that hard, round PLA does not catch on the loader mechanism. It had to be modeled in such a way that the catch would grab the stick. Modeling the stick the same dimensions as the old one already solved the plunging issue you were talking about…so, not something that actually had to be worked around.
@Alex_Koukarine again - he pushed a scrap bundle through. This was an incidental notation of the properties of the glue gun. He didn’t have to specifically work around this ‘issue’ he was simply explaining to the reader a property of how the gun worked.
The real issue came when he tried to get the loader mechanism feeding into the glue gun. So, sorry, your correction wasn’t a correction at all, but a misunderstanding on your part.
@ThantiK Wrong. For the proper feeding, he had to add teeth in the end. The issue was indeed e3xplicitly mentioned exactly after the bundle feeding testing. Read again
@Alex_Koukarine tally up the sentences talking about the loader mechanism, then tally up how much was talked about the seal… The seal was incidental and a passing notation, not nearly the centerpiece of the article/design.
@ThantiK tally scores mean nothing at all in the context. After the initial testing he has discovered two equally important to address issues: feeding grip, leaking gap. That small paragraph about that fact worth the rest of the writeup tallying. Tight cylindrical form is indeed what’s needed for the right plunger seal, so nothing to discuss further about that. Though it’s not exactly what’s needed for the feeding as he has figured later and elaborated on that in the following design v.2.
