Dialing In Ironing Settings for Flawless Board Game Insert Trays
If your 3D-printed board game insert trays keep coming out with that rough, wavy top surface instead of a smooth, injection-molded look, there’s usually one culprit: you’re not using ironing. Or you’re using it wrong. Here’s how to actually dial it in so your trays get that silky, glass-like top layer.
What Ironing Actually Does
Ironing is a post-processing pass your slicer tacks on after the top layer finishes printing. The nozzle glides back over the surface at a much lower flow rate, melting and flattening the tiny ridges left by the standard top layer pattern. It’s basically running a warm iron over a wrinkled shirt: no new fabric added, just smoothing what’s already there.
For board game insert trays specifically, this matters more than you’d think:
- Large flat surfaces (tray bottoms, dividers, card slot floors) show every single print line under normal lighting.
- Smooth surfaces stop cards, dice, and miniatures from snagging or picking up scratches over time.
- A glossy finish is what separates “custom organizer” from “obviously printed in someone’s garage.”
Where to Find Ironing Settings
Most modern slicers support this natively, you just have to go looking for it:
- PrusaSlicer/SuperSlicer: Expert mode → Advanced → Ironing (under Layers and Perimeters)
- Cura: Search “Ironing” in the settings bar, enable “Enable Ironing,” then expand the sub-options
- Bambu Studio: Quality → Ironing pattern
Can’t find any of this? Your profile is probably still set to Simple or Basic mode. Switch to Expert or Advanced first.
The Settings That Actually Matter
1. Ironing Type
Go with “Top surfaces” for insert trays. There’s rarely a reason to iron solid infill or every top-most region unless your model has weird stepped geometry. Speaking of which, “All top surfaces” is the better call if your tray has multiple levels, say a two-tier dice tray with a raised lip.
2. Ironing Flow (or Flow Rate)
Stick to 10-15%. This is how much extra plastic gets pushed out during the ironing pass. Go too low and gaps never fill in. Go too high and you’ll end up with blobbing or stringy edges along the tray walls, the exact opposite of what you wanted.
3. Ironing Speed
Slow it way down: 15-20 mm/s is a sensible starting point. At normal print speeds, the plastic doesn’t get enough dwell time to relax and settle flat. It just skims past too fast to do its job.
4. Ironing Spacing (Line Distance)
This is the gap between each ironing pass line. 0.1mm gets you the closest thing to a mirror finish, but it adds real time to your print, sometimes 20-30 extra minutes on a big tray. 0.15-0.2mm is a fair trade for most trays where “nearly perfect” is good enough.
5. Top Layer Count Before Ironing
Ironing can only work with what’s underneath it. If your top surface isn’t fully solid, ironing will just expose every pinhole instead of hiding it. Bump top solid layers up to 4-5 for PLA or PETG trays.
A Reliable Starting Profile
For a standard PLA insert tray at 0.2mm layer height, try this:
- Ironing type: Top surfaces
- Flow: 12%
- Speed: 18 mm/s
- Spacing: 0.15mm
- Top solid layers: 5
- Top layer print speed (non-ironing pass): drop to 80% of normal so the base layer lays flatter to begin with
Common Problems and Fixes
Surface still looks slightly rippled: Don’t blame the ironing pass yet. Add more top solid layers first, ironing can’t smooth over a surface that still has gaps underneath.
Small blobs or “pimples” showing up: Drop ironing flow in 2-3% steps until they stop appearing. Usually 2 rounds of testing is enough.
Ironing is eating all your print time on big trays: Widen spacing to 0.2-0.25mm, or better yet, use a modifier mesh to limit ironing to just the visible card and dice compartments instead of the whole tray footprint.
Edges of the ironed section look sloppy: Nine times out of ten this is a retraction issue happening during travel moves between passes. Try enabling “avoid crossing perimeters” or tightening your retraction settings a touch.
Material Considerations
PETG irons up beautifully thanks to its natural glossiness, but it strings more easily, so pull your flow down a bit compared to PLA. PLA, meanwhile, is the most forgiving material for dialing in ironing settings and the one you should test with first if you’ve never touched these settings before. ABS can iron well too, but you’ll want minimal enclosure airflow during that pass, otherwise large flat sections of the tray can warp on you.
Final Thoughts
Getting flawless top layers on your insert trays has nothing to do with owning a fancier printer. It comes down to giving the ironing pass the right flow, speed, and spacing, on top of a solid, gap-free base layer. Start with moderate flow (10-15%), slow speed (15-20 mm/s), and tight spacing (0.1-0.15mm), then nudge things in small increments based on what your test prints tell you. Get it dialed in once, and every insert tray after that comes out looking like something you’d find in a retail box, not a garage.