Refillable Reused Inland Spool

prusaprinters

<p>I've collected many empty spools over the years to keep them out of the landfill, but I've never had a plan for them. Recently I found that Inland (my goto filament) has expanded their spooless refill offerings to include more colors, so I want to start going that route.</p><p>My problem is that I've printed reusable spools before (for 500g spools) and haven't been happy with the results. In fact the spool I tried for the Inland refill didn't print correctly and wouldn't screw together. Printed spools also take a lot of filament and a long time to print.</p><p>Then it hit me, why not reuse some of the old spools. My first problem was how to cut the spool nicely, so I made the Saw which acts as a jig and saw at the same time. It is sized to fit inside the spool sides and hold a <a href="https://www.homedepot.com/p/Husky-6-in-Mini-Hacksaw-Replacement-Blades-5-Pack-80-530-111/304341663">6 inch hacksaw blade</a> in the center. With a bit of effort this lets you neatly cut the spool down the middle. I printed with supports under the arch, but I'm not sure they were really needed.</p><p>Next a method of rejoining the halves was required which is where the Core comes in. It is designed to print with no supports and is designed to have 4 captured M3 hex nuts inserted at each end (so you need to pause the print twice). Using M3 bolts (I used 14mm bolts as that's what I had handy, but 10mm should work) the Core can be used to reattach the halves after inserting the spool.</p><p>Holes in the spool halves are also needed for the bolts to pass through, so I created the Template which fits nicely in the center hole. I used a 3.5mm bit to drill the holes.</p><p><strong>Required items:</strong></p><ul><li>One or more empty Inland spools</li><li>One or more Inland spooless refills</li><li>8 M3x10 bolts per spool</li><li>8 M3 hex nuts per spool</li><li>6" hacksaw blade with pins at each end.</li></ul><p><strong>Notes:</strong></p><ul><li>I have noticed there is some minor variations in sizing of the spools, but so far it has not been an issue.</li><li>If the Core causes a gap in the spool when reassembled, this is not an issue as the cardboard core of the refill covers it.</li><li>The cardboard center slides over the center with enough room that it will spin freely in the assembled spool. If you are using an auto-rewind spool holder, this might be an issue. Making some paper shims should resolve that though.</li><li>All my prints were done with PLA using PrusaSlicer's 0.3 DRAFT profile for my MK3S.</li><li>Layer height shouldn't matter much, but anything less than 0.3 should definitely work.</li><li>If I was smart I would have made this an SCAD model so that it could more easily be adapted to other spool and refill types.</li></ul>