Tree vs normal supports: filament, print time and finish
The support type changes three things on the same part: how much plastic ends up in the trash, how long the printer is busy and what the supported surface looks like.
How each type holds the part up
The slicer adds support under every surface that hangs in the air at a slope below the Threshold angle, which is 30° by default in Bambu Studio. From there:
- Normal supports project the overhang straight down to the bed and fill that volume with lines. The Grid style squares the area off into rectangles; Snug follows the outline of the overhang.
- Tree supports pick points under the overhang and grow branches down that merge into trunks on the bed. Branches can steer around the part, so they land on it less often.
Bambu Studio has four tree styles: Tree Slim (thin branches, little volume), Tree Strong (thick branches, harder to remove), Tree Hybrid (normal grid under large flat areas, tree everywhere else) and Tree Organic (curved branches). The Default style picks among them.
What each one costs: two example parts
The table shows only what the supports add, compared with the same part sliced without supports.
| Type and style | T part: support filament | T part: extra time | Coat rack: support filament | Coat rack: extra time |
|---|---|---|---|---|
| Normal, Grid | 28 g | +26 min | 12 g | +12 min |
| Normal, Snug | 27 g | +24 min | 7 g | +7 min |
| Tree, Tree Hybrid | 27 g | +25 min | 5 g | +9 min |
| Tree, Tree Slim | 10 g | +30 min | 5 g | +9 min |
| Tree, Default (organic) | 15 g | +70 min | 5 g | +13 min |
Illustrative example. T part: a 60 × 60 × 4 mm top on a 15 × 15 mm column, with the top 40 mm above the bed. Coat rack: a 12 × 12 × 70 mm column with four 22 mm arms at different heights. Estimates from OrcaSlicer 2.4.2 with the Bambu Lab X1 Carbon 0.20mm Standard profile (0.4 mm nozzle), PLA Basic and every other support setting at default. These are slicer predictions, not measurements: another part or profile gives other numbers.
- Material: tree won on both parts. On the coat rack it used about 60% less than normal grid supports; on the T part, 45% to 65% less, depending on the style.
- Time: tree was not faster. On the coat rack it was close to normal. On the T part, the organic style nearly tripled the extra time, because thin branches turn into many small loops printed slowly.
- Under a large flat top, Tree Hybrid turns into normal supports, as Bambu Lab describes.
In money, the 28 g of normal supports cost $0.56 at $0.02 a gram, and the 10 g of Tree Slim cost $0.20. Cleanup usually matters more: 5 minutes removing supports and sanding, at $30 an hour, is $2.50. The material math is in the guide to cost per gram.
Surface finish: the side that was supported
According to Bambu Lab's support wiki page (checked November 2026), normal supports usually give a better finish under large flat overhangs, while tree supports use less material with a similar finish on small, curved overhangs. Three settings decide the result:
- Top Z distance: the gap between support and part, 0.2 mm by default. Larger peels off more easily and leaves a rougher surface; smaller improves the surface and sticks harder. With the same material for part and support, Bambu Lab does not recommend 0.
- Top interface layers: a denser "tabletop" at the top of the support. The default profile uses 2; at 0, the part's lines sag between the support lines.
- Top interface spacing: 0.5 mm by default. Smaller gives a smoother surface and a support that holds on tighter.
Which one to use for which part
- Figures, miniatures and organic shapes: tree, Default or Tree Slim.
- Arms, hooks and scattered details: tree, which steers around the part itself.
- A wide flat top, shelf or bridge: normal (Grid or Snug) or Tree Hybrid, so the underside comes out flat.
- Overhangs only near the base: either type with On build plate only, so no support starts on top of the part.
- A part you can rotate: none. Flipped upside down, with the top on the bed, the T part needs no support at all.
Where it is in the slicer
- Bambu Studio and OrcaSlicer: the Support tab. Turn on Enable support and pick a Type: normal(auto) or tree(auto); the "manual" versions only add support where you paint it. The style is under Style, and Z distance and interface are in the Advanced group (switch on advanced mode if you don't see them). In OrcaSlicer the organic style is called Organic.
- PrusaSlicer: Print Settings > Support material, Style: Grid, Snug or Organic. The gap is Top contact Z distance.
- Cura: the Support section, Generate Support and Support Structure: Normal or Tree. The gap is Support Z Distance.
How to remove supports without ruining the part
- Rotate the part before touching any setting. A large flat face goes on the bed; that saves more than switching support types.
- Paint where you want support and where you don't. Support painting marks enforced and blocked areas (enforcer and blocker).
- Use a different material only for the interface. PLA and PETG bond poorly to each other, and Bambu Lab published a PLA Basic and PETG mutual support guide (checked November 2026). Under Support/raft interface, pick the other filament, with top Z distance 0 and interface spacing 0, as the slicer suggests for support filament. You need an AMS or a dual nozzle, and every swap costs purge. How the two materials differ is in the guide to PLA vs PETG.
- Pull tree supports by the trunk and normal supports from the side, with flush cutters.
Common mistakes
- Raising the threshold angle "to be safe": more surfaces get support, and you get more cleanup.
- Top Z distance 0 with the same material: the support fuses into the part.
- Turning on variable layer height while counting on organic trees: Bambu Studio won't combine them, and Default switches to Tree Hybrid.
- Leaving cleanup out of the quote: it is labor. More slips like this are in beginner mistakes.
Frequently asked questions
Do tree supports work on printers that aren't Bambu Lab?
Yes. The support type belongs to the slicer, not the printer: OrcaSlicer, PrusaSlicer (Organic style) and Cura (Tree) generate tree supports for any printer they have a profile for.
Why didn't the slicer add support where it was needed?
Usually the surface is above the threshold angle, Remove small overhangs dropped the area or, with tree supports, the span was treated as a bridge. Paint the area with the enforcer or lower Max bridge length.
Can I use less support material without changing the type?
Yes. On normal supports, increase Base pattern spacing. On tree supports, the Lightning base pattern is the leanest. Independent support layer height prints the support with its own, thicker layers, and it is on in Bambu's profiles.
How soon after printing should I remove supports?
With PLA there is no rush. For nylon and moisture-sensitive supports such as PVA, Bambu Lab recommends removing them within 2 hours: after that the material softens with humidity and comes off worse.