“A chicken is just an egg’s way of making another egg”
How true of RepRappers and our 3D printers.
Since I got my 3D printer, about half of what I’ve done with it has been upgrading or fiddling with the printer itself, slowly fixing issues, or just trying to make it easier to hit GO and let it print my creations. Don’t get me wrong, I’m not saying that any of this is in any way bad. Almost all human endeavours are aimed at just having fun, or making it easier to entertain ourselves. I find this tinkering very entertaining, and it helps exercise the Tinkerer part of my brain, which doesn’t always get the love it deserves during normal life.
Anyway, one thing that has always bugged me about my printer is the filament spool holder. When I first got the machine, it was a piece of HDPE pipe taped across the top of a box… “just to get me printing”. I won’t show a photo of this. It was embarrassing.
Then I printed some brackets to support a rod (again, HDPE pipe, because I have 25m of it under the house after plumbing up a garden tap). An improvement, as I could now put the lid on the box with some desiccant inside to keep my filament dry, but still not great. The pipe was low friction, so it turned well, but the pipe would sag, and end up with the filament roll touching the bottom of the container.
I then found some awesome, rigid plastic tube, which worked a lot better, because it didn’t sag.
The problem, aside from the extra space required on my printer bench, was the tendency for the filament to snap between the machine and the roll, if left connected for more than about a day. I suspect that this is because of the curves that the filament had to go through to get to the machine. It’s curved on the spool, curves to get horizontal out of the box, then flattens out to go horizontal, and then curves again to get into the printer. I suspect that the reversing curves just increase the stresses in the filament, and the changes in temperature in our house throughout the day cause it to finally fail.
I hope that this issue will be eliminated through my latest upgrade.
When I had been building the printer, I did forsee something like this happening, so I put in a few spare T slot nuts, since I knew that I wouldn’t be able to access the ends of the extrusion without diamantling structure… screw that. Of course, the problem is that I didn’t put ENOUGH nuts in. That’s alright, I just designed and printed some twist-in nuts, which actually worked REALLY well. Here’s the design:
See my Thingiverse page for the spool holder design, http://www.thingiverse.com/thing:260864
And you know what?
It doesn’t look half bad.