Filament Spool Holder - 3D Printer - MP Select Mini

Something that bothered me immediately with the MonoPrice Select Mini 3D printer was the filament holder arm.  So i decided to revise it.

Filament Spool Holder - 3D Printer  https://youtu.be/NSb7RtlGY34

I didn’t like the fact that it was made of square steel and that it was mounted at 90 degrees to the printer. It didn’t spin smoothly and pulled the filament at an odd angle. And i had some issues with the filament binding on each other. Here's what the stock filament arm looked like on the MP Select Mini.

 The main problem was with friction, the spool did not spin easily. I assumed that there would be something that i could just print off to fix the problem, since there's lots of 3D parts on Thingiverse to upgrade the printer (knob, guides, supports). And i did see some support arms that looked like they would work, unfortunately when i read in the details, they could not be printed with the MP Select Mini printer. The support arm needs to be pretty large to get the spool far enough away from the printer, at least 6" because of the size of the spool, and this printer wasn't large enough to print that.

This is when i was toying around with some type of bearing.

There's an old saying that if you give someone a hammer, everything looks like a nail. Well when someone gets a 3D printer, everything looks like it needs to be 3D printed. But i figured that it would be much stronger and easier to just build a wood arm to hold the filament roll. The trick is always in keeping it simple. 

So what i did was this as version 1:

The very simple shape, cut-out and hole.

Originally i thought i would have to drill into the metal printer support plate to attach it, but i saw another person's design where they just cut a groove into the part and it was held in place with friction. So i copied that design and that's how i attached the arm. 

 I thought it was a good first design, but it didn't work, the roll did not spin smoothly. The arm was good but the wooden spool was not. I could have fixed this in 2 seconds, but instead i got the idea in my head that i needed to make it more complicated by adding a metal bearing.

Another design and simple bearing.

And another version of a series of tubes and barrels.

Here is the start of version 2.  The same basic shape, except i mounted the VCR bearing into the wood.

Here it is tapered down to the wood dowel.  Again, i can't believe that i didn't see the obvious solution at this point.

The mix-mash of parts needed.

Now it spun incredibly smoothly, the bearing was from an old VCR. But it wasn't very strong and overly complicated and bulky. That's when i realized that the problem was with the wood dowel. So i checked to see how the roll would spin on a PVC pipe. It turned out that it spun very easily. 

So i went back to my original design and made this, version 3:

It couldn't be more simple, no moving parts.

And i added a slip on end cap to keep the spool from spinning off.

Here it is from the side angle.

I used a 2" PVC pipe, which fit well inside of the hole in the spool. I was always happy with how the arm attached to the printer so that design never changed. Plus with that design i could slide it up and down as needed to get the alignment right. I cut the groove with 2 different hand saws. The first saw was a Japanese pull saw that i used to get the first cut. Then i used a larger hand saw to get the width correct. It had to fit tightly but have enough pressure to be removed.

Here's all the different parts and 3 versions.

I suppose that it might spin even easier if it was coated with wax or a clear lacquer spray, but i haven't had a single problem with just the PVC. And with prices of 3D printing becoming costly at every corner, it's nice to make something that doesn't cost anything. 

The numbers you need to know before building this are: Spool/Roll size: Width = 3" Diameter = 8" (you need this to know how far away to center the spool from the printer, +-5") Median filament point coming off the roll (when the roll is full the filament comes from the edge, when empty it comes near the center, i lined it up with the middle of the roll) Inner Hole Diameter = +-2.5" (2" PVC fits fine, but there are lots of adapters online that you can print and change to fit any pipe size)

Here are the AutoCad drawings i made for the spool holder.

This is the basic shape to show the alignment to the feeder.

And this is just the basic wood pattern itself.

This is a great modification that you can easily make for your printer, which prevents any clogging and jamming from stuck filament.