Retracting Dry Box

This is a Dry Box to go with the Universal Auto Retractor by Vincent Groenhuis. There are slot in parts to help the system stack together, so that rather than mounting to a wall you can stack the units. A wall mount option and a version with no meter MAY be forthcoming.

I designed the box, but not the retraction unit, you can find the original here:

https://www.thingiverse.com/thing:3338467

The only item designed by them that I have modified is the axle which I shrunk very slightly. There are also a couple of extra nuts and some different springs there, I have included the stiff flat (which I use) and the modular (the most recent) here for ease of download.

There are also assembly instructions for the retractor there.

All credit for the design of the retraction system has to go to Vincent Groenhuis (https://www.thingiverse.com/vincentgroenhuis/designs)

Print Settings

Printer Brand:

Prusa

Printer:

MMU2s

Rafts:

No

Supports:

No

Resolution:

Varies

Infill:

15%

Filament:
3DQF PLA Black

Notes:

When the box is facing towards you (the meter / tube are pointing in your direction) the retraction unit should be on your right. I have the clutch one of maximum for my MMU2S.

I print the box parts (Except the plug) with a 0.8 nozzle at 0.4mm for speed (the print is still 12 hours for the Compartment and another 12 for the lid) All of the retractor parts and the two slot in holders are printed with a 0.4 Nozzle at 0.2mm. I have used PLA for everything.

I print on a Prusa, and be wared there can be lifting at the edges with this size of print, I have found that glue and a brim works to minimise this to the point it does not effect the print, and am experimenting with sanding the bed.

To keep things extra airtight you can put a wrap of electrical tape round the join (it was the most efficient system I could come up with)

The base will take a 250g bag of desiccant comfortably, and will still work with two if you need it exceptionally dry (e.g. for PVA). There is a link for the bags I have used below (along with all external parts) I would make sure you have freshly dried them out before inserting - this will bring down the humidity as quickly as possible.

Not that if you weigh the system, the desiccant will change weight as it absorbs liquid. I intend to leave one out and measure it at both ends - I will include the measurements here when I have them.

I have used this with 4mm OD 3mm ID PTFE Tube, I am reliably informed that 2.5mm is best, but I was struggling to find any.

I would glue the meter in place, I used UHU glue as it is slightly rubbery so should help keep the seal, but anything that keeps it tight will do.

There is a plug to go in the nozzle what will hold a short length of filament should you choose to have extras for storage.

External Parts:

M10 OD4 Nozzle
https://smile.amazon.co.uk/gp/product/B07R77LD4G/ref=ppx\_yo\_dt\_b\_asin\_title\_o02\_s00?ie=UTF8&psc=1

Hydrometer
https://smile.amazon.co.uk/gp/product/B07JG9TFSB/ref=ppx\_yo\_dt\_b\_asin\_title\_o01\_s01?ie=UTF8&psc=1

Desiccant
https://smile.amazon.co.uk/gp/product/B089WD6F6K/ref=ppx\_yo\_dt\_b\_asin\_title\_o01\_s00?ie=UTF8&psc=1

PTFE Tubing
https://smile.amazon.co.uk/gp/product/B0915BL5XQ/ref=ppx\_yo\_dt\_b\_asin\_title\_o06\_s00?ie=UTF8&psc=1
Note that you have to select the right size, at the time of posting they did not have any 0.3 ID 0.4 OD.
https://www.ebay.co.uk/itm/121056068011
That is 0.25ID 0.4 OD but I have not tried it.

Feel free to remix, a link would be nice if you do.

Category: 3D Printer Accessories