Filament Fishing Rod Guide Clip - Prusa i3 MK3

thingiverse

This is a simple filament 'fishing rod' guide that has several benefits, similar to how a fishing rod works. It uses the inherent tension in the plastic to absorb the unreeling of the roll, just like a fishing rod bends when a fish jerks on the line. Originally, this thing was intended as a long filament clip/guide, but after building it I realized I found something much better than expected. By not making it stiff and incorporating Bowden tubes between the polybox reel and the guide, the guide absorbs the jerks and flexes rather than your filament, just like a real fishing rod does. It would be great to show a video of this thing in action - as you print, it moves constantly, proving that there is a lot of tension in the line that should be absorbed and not transferred to the filament. - Absorbs flex on the line and acts as a tension absorber, so the line doesn't get overly stretched as it unreels, and the filament is not stretched as it feeds into the extruder, leading to better prints and fewer failures. - It fits perfectly onto the crossbar with two zip ties and can still be slid across to reposition. - The hole position is 132 mm above the top of the top bar, which is well above the fish/extruder. This creates a long straight path to the extruder so the filament path into the extruder is straight and direct. - The hole is 6.5mm in width and holds a ~6ish mm Bowden tube nicely, such as the one I am using from PolyBox Edition II. - It can also be used to store the second line of filament if you have the other going directly to the extruder (see last pic). Use my Bowden coupler on Thingiverse. I designed this guide clip after getting a PolyBox. I wanted a supported path to the extruder from the box. Originally, though, I needed this with the PolyBox, but it turns out the stiffness of the Bowden tubes from the PolyBox are self-supporting if you place the box to the left, right, or rear and let the tubes out of the top of the box so I didn't need any sort of guide. In reality, with a dry box, you have three options to connect: - Have the Bowden tube go to a support, and then have the extruder pull the filament between the support and the extruder (this solution used with this guide clip). This has the obvious advantage of adding tension with the clip, but the material isn't enclosed from humidity between the clip and extruder. I think the tension benefit is key, though, and use this option now. - Have the tube go through the Bowden tube all the way to the extruder with no support (I show this in one pic). It's using my Bowden coupler https://www.thingiverse.com/thing:3372591 to help, because I found out the stiffness of the Bowden tubes doesn't require any support. This is the simplest solution if your tubes are short and their stiffness supports it. - Have the tube be guided by a support, but then continue all the way to the extruder. This clip can do that, but you need to file the hole out a half mm or so to get the tube to go all the through it. This is required if the drybox is some distance from the printer and the tubes can't easily be self-supported - A good solution would be to place Bowden tubes on either side of the tension holder and use my clip at the extruder end too. In summary, this is attached via two zip ties to the top bracket on the Prusa. It holds the filament up at the same height and position as a normal spool so it has plenty of movement distance to the extruder. Ideally, you also have a dry box feeding the filament via a Bowden tube of 6.5mm width. The one that comes with the PolyBox Edition II is perfect. I intend to use this to hold the tube from my polybox drybox and feed the Bowden tube through that hole at the top. It doesn't go all the way through, though. Use supports but they are only for the line hole.