DIY 3D Printing Sink Filter Guide

• 1
  Why a printed basket beats a store-bought strainer
• 2
  Basket geometry: the numbers that decide fit and flow
• 3
  Hole and slot design for real drainage rates
• 4
  PETG, PLA, or something else: material boundaries
• 5
  The three failures you will actually hit
• 6
  When plastic is the wrong answer
• 7
  FDM plastic versus machined stainless for a sink strainer

Store baskets come in a few standard diameters. A kitchen strainer flange is usually Ø 82 to 90 mm, but bar sinks, older cast-iron drains, and utility tubs drift well outside that range. The basket either drops through the opening or sits proud and leaves a gap where food collects. Printing removes that constraint: you measure the real drain and model to it.

The second reason is the hole pattern. A stamped basket has one hole layout for every kitchen. If you cook rice, coffee grounds, or coarse vegetable scraps, you want long slots on the outer wall and a tighter grid in the base. That is a modeling decision, not a manufacturing one.

Third: iteration cost. A printed basket takes 40 to 90 minutes and a few grams of filament. You can test three flange depths in an afternoon. That is the entire argument for the DIY 3D printing sink filter approach, and it holds as long as the part stays cool and lightly loaded.

Start with the flange. Measure the drain opening with calipers at three points; cast iron and ceramic sinks are rarely round. Model the flange 0.3 to 0.5 mm under the smallest measurement. A loose basket rattles and leaks debris past the rim. A snug one is hard to lift out with wet hands, so add a 6 to 8 mm lift tab on the rim.

Depth matters more than most people expect. A shallow basket overflows and floats. Aim for 25 to 40 mm of basket depth below the flange for a kitchen sink, 18 to 25 mm for a bathroom basin. The base should sit 3 to 5 mm above the drain cross-bars so water can still pass if the basket is full.

Draft the walls at 3 to 5° inward. Vertical walls print fine but trap food in the corner radius. A slight cone lets debris slide out when you tap the basket. Keep the base fillet at 2 mm minimum; a sharp internal corner is where layer adhesion fails first.

• 1
  Flange clearance0.3–0.5 mm under the smallest measured diameter
• 2
  Wall thickness1.6 mm minimum, 2.4 mm if the basket is handled daily
• 3
  Base clearance3–5 mm above the drain cross-bars

Open area drives flow. A basket with 12 percent open area drains noticeably slower than one at 25 percent, and the difference shows up the moment you pull the plug on a full sink. Target 20 to 30 percent open area spread across the base and the lower third of the wall.

Round holes print cleanly down to Ø 2 mm with a 0.4 mm nozzle. Below that, bridge sag closes the top of the hole. If you need finer filtration, use Ø 1.5 mm holes on the base only and keep the wall slots wide. Long slots 2 mm wide by 12 to 18 mm long print with less stringing than a dense grid.

Spacing matters for strength. Leave at least 1.5 mm of material between adjacent holes. A wall perforated too densely cracks along the hole line when someone presses the basket into the drain. Stagger the rows rather than aligning them; the offset breaks the crack path.

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  Target open area20–30 percent of the wetted surface
• 2
  Minimum clean holeØ 2 mm with a 0.4 mm nozzle
• 3
  Web between holes1.5 mm minimum, staggered rows

PETG is the default for sink parts. It handles continuous hot water around 60 to 70 °C without softening, tolerates dish soap and mild bleach, and bonds well between layers. Print it at 235 to 250 °C nozzle and 80 °C bed, and dry the spool first; wet PETG foams and leaves gaps that grow into leaks.

PLA is easier to print but has a hard ceiling. It starts to soften near 55 to 60 °C, which is exactly the temperature of a hot tap running into a basin. A PLA basket may survive for weeks and then sag into the drain. Use it for a prototype to check fit, not for the final part.

ABS and ASA resist heat better than PLA and cost less than the engineering grades, but they warp on a tall thin basket and smell during printing. If you need higher temperature or chemical resistance, go to a different process entirely rather than chasing exotic filament.

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  PETGBest all-round choice for hot water and soap
• 2
  PLAFit-check prototypes only, softens near 55 °C
• 3
  ABS / ASAMore heat resistance, but warps on tall baskets

Warping at the base is the most common defect. A 3 mm base on a Ø 85 mm basket cools unevenly and lifts at the corners. Fix it with a 4 mm brim, a 60 to 80 °C bed, and a draft shield if the room is cold. Reducing base thickness below 2.5 mm makes the problem worse, not better.

Clogged holes come second. Stringing and z-seam blobs bridge small openings. Set the seam to a single aligned position on the outer wall, away from the perforated zone, and enable a small retraction. If holes still close, the nozzle is too hot or the flow is over 100 percent.

Rim cracking shows up after weeks of use. It usually means the flange is too thin or the layer direction runs across the lift tab. Thicken the rim to 2.4 mm and print the tab as part of the wall, not as a separate arm sticking outward.

• 1
  Base liftAdd brim, raise bed to 60–80 °C
• 2
  Closed holesMove the seam, check flow and nozzle temperature
• 3
  Rim crack2.4 mm rim, integrated lift tab

A printed basket is a good fit for a home kitchen, a workshop sink, or a prototype you want to test before committing to tooling. It is a poor fit for a commercial dishwasher line, a food-processing drain, or anywhere the part sees steam and heavy impact daily. Plastic creeps, stains, and eventually fails at the rim.

The switch point is usually a combination of temperature and load. If the basket sits in water above 70 °C, or holds a steady weight that presses on the rim, or has to survive a commercial cleaning cycle, move to metal. The same geometry you validated in plastic translates directly to a machined or metal-printed part.

That is where we come in. GreatLight machines stainless 304, 316, and 316L on 5-axis centers to ±0.005 mm, with fine perforations and Ra 0.8–1.6 μm finishes that wipe clean. A printed prototype plus a machined production part is a normal path: validate the fit in PETG, then cut the real basket in stainless.

• 1
  Stay with FDMHome kitchen, low volume, fit validation
• 2
  Move to metalAbove 70 °C, steady rim load, commercial cleaning
• 3
  TransitionValidate in PETG, then machine in 304 or 316L