RespoolBGone Universal Spool

Update July 3, 2025: Added support for MakerLab Customizer to create custom hubs

Besides the use which I will outline below, this model can also be used as a somewhat-universal spool for filament refills of different brands:

Are you constantly having to respool filament that comes on cardboard rolls in order to use it in your AMS?

Make respooling a thing of the past with RespoolBGone!

When I first got my AMS, I thought there was already a good solution to the cardboard spool limitation - 3D printable rings that fit around the edge of the spool. Unfortunately, even using these rings I seemed to have no end to problems with the cardboard spools, so I built a respooler. It works, but it's a lot of hassle. It's time consuming, and often difficult to get nice, neat, evenly wound rolls.

I learned recently that on certain cardboard rolls of filament you can rip the sides off and directly attach it to a Bambu reusable spool. I have had luck doing this in the past with both eSun and Elegoo rolls, however with my latest order of eSun spools the inner diameter was too small for this trick to work. Unfortunately I didn't notice until after I'd already torn off one of the sides of a spool, so I decided to make my own spool to solve the issue. I also wanted to do it in a way that I wouldn't need to print an entire new spool every time I buy some filament and the inner diameter changes a bit. This is what I came up with. It has the following features:

1. Springy Hub - The hub is designed in a way that you can compress it to fit in to cardboard spools with a wide variety of different inner spool diameters
2. Modular - Hubs of different sizes can be made to accomodate any number of inner diameters or spool widths without having to print the sides every time. The modular design also allows you to reprint a piece if something gets broken without having to reprint EVERYTHING.
3. Labelled “bolts” so you can easily mark the material type on the side of your spool. You could also colour-code them if you want.

To use it, tear one side off of your cardboard spool. Be very careful on this step that you don't allow any of the filament to slide off the roll sideways. Select a hub that fits your spool and push the hub in to the center of the cardboard spool (you will need to squeeze it to make it fit). If the cardboard spool is wider than your hub, it still may work, but try to position the hub roughly in the center so that you will have good thread engagement on both sides. Put one of the sides on, and thread the bolt down until it engages with the side, then use the side piece to turn it the rest of the way, but don't fully tighten yet, just make sure it's tight enough that filament won't slip off the side. Flip over the spool, tear off the other side of the cardboard spool, and thread on the other side the same way. Now tighten both sides until it is snug.

When selecting your hub, it is better to choose one that is slightly smaller than the width of your spool over slightly larger to ensure a tight fit against the sides of the filament. Also choose one with a diameter that is at least a bit larger than the inner diameter of the cardboard spool so that there is some tension against it once installed.

With the initial release of the project I've included two hubs. The larger diameter one has been tested on rolls of Polymaker and eSun that I have on hand. If it works for you on other brands, leave a comment to let people know what else it works with. For the polymaker I only had to compress it a bit, and for eSun I had to compress it a lot.. and of course it should fit anything with sizes in between. If you have a roll it doesn't work with, measure the width and inner diameter of your spool and I will try to make you a working hub for it. The smaller diameter one is designed to fit the eSun rolls a lot better. It has also been tested and works well with the cardboard spools from Matter3d.

Please note that once this is installed the center hole will be blocked so you will no longer be able to use your spool on the external spool holder. Also, be aware that if plastic is in tension over a period of time it will deform. If you've compressed the hub a lot, it likely won't return to its original diameter. You can pull the two wings to try to stretch it out a bit, but likely you'll want to dedicate some hubs for smaller diameters and some for larger diameters, and you will no doubt need to print new ones once in awhile.

Final Note: I know there is at least one other similar project to this. I didn't know it at the time I made this, and I did spend a lot of time on this and I feel it has its own benefits, so I'm posting it anyhow. Hopefully others find it useful.

Here is a short video demonstrating how to use it: