(Adjustable) Oxo Rapid Brewer Basket Adapter

Tweaks @italic's version to Just Work™ with a wider range of hardware. Outer diameters are slightly relaxed in the design and vertical heights are completely adjustable using 0.5mm shims.

First assembly instructions:

1. Acquire a Moka Pot gasket and 51mm espresso basket (linked below). 

2. Print the adapter model in something food-safe.

3. Print shims. Two of each should fit easily on a plate.

4. Use large shims to level the Moka Pot gasket with the outer rim of the adapter.

5. Remove the gasket but keep the large shims inserted.

6. Insert the espresso basket into the adapter. If using a shower screen, place that on the basket too.

7. If the basket/shower screen are not flush with the outer ring/large shims, remove the basket and add small shims to get level.

Fit-check tips:

• With the adapter fully assembled, check the vertical space between your basket/screen and the Moka Pot gasket. They should be gently sandwiched together. If not, add more small shims.

• As you screw the adapter into the ORB, you are creating two seals. First, the ORB's plastic shower screen should make contact with our Moka Pot gasket. You will feel some resistance here. Then, the plastic rim of the adapter seals against an O-ring built into the ORB. At the right angle you can watch daylight disappear between the brewer and adapter as this happens.

Help, it's leaking! This part screws in with force similar to the original basket. If you have to torque it on there to fix a leak then something is wrong.

• Water through the ORB threads = your rubber gasket is too tall and preventing O-ring seal. Remove large shims.

• Water around the basket = bad sandwich seal between ORB plastic shower screen and the basket. Add small shims.

Print tips:

• This part does not require tight tolerances. 0.32mm layer height with thick line widths is perfectly adequate.

• This part does not require ironing. It can help, but PETG is sticky and likes to ball up as it is ironed so it may be more trouble than it's worth. Lightly sanding surfaces is always an option too.

• Your brew is hot enough to make most filaments ductile at point-of-contact with the metal basket. This can cause the ring securing the basket to contract over time. If this happens, the interior lip is thin enough that a knife or sandpaper will open it back up. Also, consider annealing (instructions below).

• Full infill is not required but is recommended. The original post's 15% recommendation is sufficiently strong.

• It's OK if the outer threads turn out ugly. They're just there to provide clamping force.

Annealing. This part benefits from annealing. The process will protect your adapter from further deformation due to brew stress. It also tightens up layer lines that are a potential conduit for moisture to accumulate and make our food-safe filament not-so-food-safe.  This is especially simple if using the linked Comfy Materials PETG as it has excellent dimensional stability. To anneal with this material, scale the part in your slicer before printing using the following factors:

• X: 100.8%

• Y: 100.8%

• Z: 100.4%

I used 0.2mm layer height, a medium-fast print speed, and full infill. Snug supports can make for cleaner threads if that matters to you.

Example steps:

1. Select an oven-safe container that is large enough to hold the adapter.

2. Line the container with salt, sand, or another oven-safe material.

3. Place the adapter in the container and fill to cover with your sandy material.

4. We want a cycle of gently warming and gently cooling the adapter. Bake at 230F / 110C. Allow about 30 minutes for the material to warm, plus 60 minutes to anneal, for a total oven-on time of about 90 minutes.

5. When done, turn off the oven and allow the part to cool with the door closed.

6. After 30-60min of cooling the part can be removed and cleaned.

Links:

• Moka pot shower/gasket (use ~1 large shim)

• Perfectly adequate basket (use ~2 small shims)

• Fancy basket (use ~1 small shim)

• Dosing funnel model (excellent in ABS with acetone smoothing)

• Food-safe PETG (recommend black)

- Shout out LH. We're brewing something tasty today.