Plastic House Dry Box Spool Holder Self Contained /w Hygrometer

Part of my Plastic House Dry Box set.

This is also composed of the PC4-M10 Drybox passthrough with cap which you can find here:

https://www.printables.com/model/789995-pc4-m10-drybox-passthrough-with-cap

And the latest release of my Spool Hub Desiccant Holder which you can find here:

https://www.printables.com/model/789915-easy-open-spool-hub-desiccant-holder-r3

For the this portion of the assembly you'll need:

The ubiquitous Plastic House Cereal Storage boxes (this is designed specifically for this exact product):

https://www.amazon.com/dp/B08YQN42HD?psc=1&ref=ppx_yo2ov_dt_b_product_details

608 Bearings (4 per box):

This time around my previous bearings weren't available and after scouring the reviews I went with these:

https://www.amazon.com/dp/B07JB2Y4H3?psc=1&ref=ppx_pop_dt_b_product_details

About the boxes:

I ordered 3 sets of the Plastic House sets (they only let you buy 1 per order to I just ordered a set a day).  

I wanted enough of them to have my more commonly used PLA/PETG/ASA filaments always ready to use without shuffling them.   The first two sets were fine but the 3rd batch was a tad brittle and when I went to use my spring center punch before drilling the holes for the feed through (separate model), the 3rd batch shattered so make sure you really brace the inside with your hand before using one.  

About the bearings:

I use a lot of these things, and periodically just order a batch of 100 of em.  My “go to” for the past few years now longer exists on amazon, so I had to find a new vendor.   These weren't the absolute cheapest, but were close and had the best reviews.   They are pretty gummy though (way more so than the previous vendor) and you'll want to soak em in some GumOut and then IPA after that to get whatever gawdawful grease they used in order to get them to roll free.   I tried just IPA first and that was taking too long so I went to GumOut followed by an overnight soak in IPA.   Most cleaned out pretty easily and maybe 10-15% took a few goes to get to “near fidget spinner” roll-ability.   Even cleaned up they aren't a top notch bearing but for this application, they're fine.

I also found some minor variations in the inner diameter of the races which led to some of them not staying real well on their posts.  A wrap of blue painters masking tape cured that on the 4 or 5 that wouldn't stay on, and minor issue, especially considering the bearings are under $0.20 a pop.  If this was a load bearing mission critical application I'd lose the more out of spec ones, but again for this?  They're fine.

So why another Plastic House Dry Box?

There's several out there, and some are really nice.

However I didn't like the notion of doing 3 prints per box (one for the spool base, another TUSH print to put ON the spool base, and a 3rd print just to mount the hygrometer.

So why not have a single print that does it all instead of making a stand for a TUSH?

Oh yeah, supports.

However, as a happy 5TH XL owner, and as a result being able to use PLA for PETG supports and vice versa, I no longer have those design constraints, and this was a good place to put that to use.

So this DOES require supports (although if you were clever with your slicing setup you might be able to get away without them).  

All in one.   Spool Support / Bearings / Hygrometer. 

I print these 4 at a time on the XL, using 0.6mm nozzles and variable layer height in the slicer in the bearing shaft area.

The “Ensured” Fit.   

I'd noticed that several of these things (and not just for the Plastic House flavor) had multiple models and makes / remixes done because it wouldn't fit this spool or that spool or whatever.

I didn't really want to have a bunch of variants of this thing and have to keep track of which spools fit in which versions.

Prior to making the model I measured every brand of spool that I had and located the bearings in all 3 axises to specifically ensure that all the spools will work on it:

Old Style Prusament
Current Style Prusament

Overture
CC3D Old
CC3D Current

IIIDMax (Old Spool)

IIIDMax (New Spool)
MatterHackers
Sunlu

I took the measurements off the actual spools (Diameter, Hub Width, Flange Inner and Flange Oute) and laid them out in Rhino to plant the bearing offsets so regardless of what I used spool wise, the flange will sit on the bearings (Partial below):

 

In order to “ensure” the spool will land where it needs to I sacrificed one of the containers to get exact measurements of the base and take advantage of the slight raise in the center of the box to “lock” the holder in place and make sure that all the placement math I did above will be present.

I also went through a couple design iterations before settling on the current version, as I needed to keep those bearings exactly where they are or otherwise some spools would work and others wouldn't if there was too much flex in the walls, which is part of the reason there's a riser that goes all the way around the perimeter of the box in order to ensure enough structural rigidity to keep the bearing position where it is in the X plane.

About those supports:

 As mentioned previously I use the 5TH XL to do PLA supports on PETG and vice versa, and for the most part it works really well.

So here I'm using a hybrid of the automatic painting (using 34 for the angle), and manual smart fill for the bridge over the Hygrometer (which is set to 9 degrees).   A single click on the full overhanging face will pick up the beveled front edge as well.
 

Post Processing

The prints come out like this:
 

To remove the bearing supports I just grab the centers with a pair of needle nose pliers and pull straight out from the wall and they pop off in a single piece very easily.

The Hygrometer support pops out pretty easily by pushing against it from the inside out and it'll come out in a single piece as well:

Now I've only done 3 runs of these and as such haven't totally dialed in the optimum setup for the bearing supports and on some of the prints running 4 up, there's been enough cooling that the PLA supports have contracted a bit and the first layer or two aren't completely supported giving the underside a tad of a lopsided affect in a few of the prints.  

The bearings still fit fine though, aside from the minor oversize issue on a few of em mentioned above.

The Passthrough Back Nut
 

I tried this passthrough for the PC4-M10 connectors:
 

https://www.printables.com/model/295764-pc4-drybox-feeder-with-knurled-screw-on-cap-m10m6
 

I couldn't get the cap to mate with the plate despite a couple of test print adjustments to the XY scale on the parts, so as a result cadded up my own, which is below.

However I was able to get the the BPT nut for the PC4-10's threads did work ok (with some % XT size adjustment, as the nut threads were initially too small to fit on the connector.)

So my from scratch model of the front side pass through is this:

My  Passthrough Front Nut Nut & Cap

https://www.printables.com/model/789995-pc4-m10-drybox-passthrough-with-cap

Spool Hub Desiccant Holder:

So the whole point of these things are to keep your filament dry, and for that I use desiccant holders in the spool hub, both in and out of these dryboxes.   For non dry box storage, I put one of the holders in the spool hub, stick the spool back in the ziplock bag an suck the excess air out with an oversized straw before at the end of the zip and put em back in the box for storage.  I've got rolls I've stored this way for 4 years with no issues, provided you check the desiccant every 6-9 months in case you've inadvertently opened the zip up.  

For the Dry boxes I each of these gets it's own dedicated desiccant holder.

You can find the desiccant holder here:

https://www.printables.com/model/789915-easy-open-spool-hub-desiccant-holder-r3

Usage notes:

I used the labels that come with the boxes to keep 2 bits of data:

The overall dry weight:  Box, Holder w/ Hydrometer and all the Fittings.   

That way I can toss the whole thing on a scale with the filament, and knowing the dry box weight and the desiccant holder weight I can subtract that from the total to know the Spool + Filament weight to know if there's enough left on the spool for whatever print I'm going to do.

The Date and Weight of the Desiccant holder when put in service.

Once I get a firm feel over time as to just how much weight in water the desiccant can take on, I'll have a good basis of knowing when it's time to change, regardless of the color.   I keep a running log on a sticky note inside the box as to the weight changes over time, as I hadn't bothered doing this initially but found I'd managed to forget to check some of the spools and ended up with some pretty soggy filament on a few rolls.