Video summary
LAYER ADHESION TESTED: Bambu Stock vs TZ 3.0 vs E3D HF ObXidian hotends (220C vs 240C)
Main summary
Key takeaways
Summary of product test (hotends): Bambu Stock vs Bambu TZ 3.0 vs E3D High-Flow ObXidian (CHT)
Test setup / method (key details)
- Compared three hotends on the Bambu Lab P1S, using stock heater + thermistor for an “apples-to-apples” comparison.
- Stock Bambu Lab hotend (tested at 220°C and 240°C)
- TZ 3.0 (tested with a hardened steel nozzle + copper insert, including Boron Nitride paste for best case)
- E3D High-Flow ObXidian (CHT-style design that splits flow to heat faster)
- Material: Bambu Basic PLA (purple)
- Layer adhesion measurement:
- Custom test print cut into 20 pieces per flow rate
- Broken with a tensile strength testing machine
- Additional samples printed vertically to assess strength loss from layer-by-layer construction
- Test accuracy improvements:
- Reinforced the tensile tester to reduce flexing (custom stiff holders; sponsor-machined steel holders mentioned)
Main results by hotend
1) Stock Bambu Lab hotend
Core findings
- At 220°C: “very unimpressive”
- Layer adhesion drops quickly as flow rate and speed increase.
- At 240°C:
- Significant improvement, even at slow printing
- Maintains up to about 200 mm/s (with “regular settings”) with almost no loss in layer adhesion (within the tested range).
Numerical comparisons
- With 15 mm³/s flow rate:
- About 3% under extrusion
- Layer adhesion drops about 35% in strength as flow increases
- Interpretation: max flow / extrusion stats are misleading for predicting adhesion.
Verdict (stock)
- Stronger at higher temps (240°C), but still not competitive with the E3D High-Flow in adhesion at high throughput.
2) E3D High-Flow ObXidian (CHT design)
Core findings
- Completely outperforms stock Bambu hotend in layer adhesion at high flow/speed.
- Adhesion curve behavior:
- Noted strange flattening at higher speeds/flow (interpreted as less time to cool down, enabling better bonding).
- Testing was capped to avoid misleading interpretation (without the cap, the drop-off might look steeper).
- At 240°C:
- Adhesion curve is described as nearly a perfectly flat line.
Claim validation
- E3D’s “60% flow rate improvement” claim is described as spot on.
- Review emphasis: flow rate alone doesn’t explain the advantage—hotend design drives the adhesion gains.
Numerical/relative performance
- Maintains comparable layer adhesion while printing at about twice the speed/flow rate versus stock (as described).
- Reinforces the “max flow tells so little” conclusion: stock loses adhesion badly even when flow metrics look okay.
Verdict (E3D)
- Best overall for maintaining/boosting layer adhesion under high throughput.
- Pricing around ~$75 (before shipping/taxes) is framed as reasonable relative to performance.
3) Bambu TZ 3.0 hotend
Core findings
- Tested with a hardened steel nozzle + copper insert plus Boron Nitride paste.
- Main result:
- Barely higher adhesion at 240°C compared to stock Bambu at 220°C.
- At 25 mm³/s, the stock heater lacked power:
- Had to drop temperature by ~4°C to stay within power limits
- Swapping in the included 60W heater fixed the temperature issue
- After fixing temperature:
- Adhesion was reported as identical, around 12 MPa.
Insert/nozzle material conclusion
- Concern raised about cooling/hotend design compatibility (possible heatsink fan impact).
- Further testing suggested copper inserts are generally bad for adhesion when measured directly.
- The only nozzle option mentioned as improving adhesion:
- Nickel-plated copper insert (better than hardened steel + copper insert approach)
Vertical strength test
- Vertical orientation samples (PLA): all around ~67 MPa consistently.
- Suggested baseline print strength despite stacking effects.
- Maintaining around ~60% of original material strength even with layer-by-layer printing.
Verdict (TZ 3.0)
- Underwhelming for layer adhesion, especially with the tested copper insert combinations.
- Hardware/thermals can limit real performance, and insert choice matters a lot.
Comparisons made (explicitly emphasized)
- Max flow rate / under-extrusion numbers do not predict layer adhesion.
- Example: stock hotend showed low under-extrusion at 15 mm³/s, yet lost ~35% adhesion strength.
- E3D High-Flow vs Stock Bambu
- Stock improves with higher temperature (220°C → 240°C), but
- E3D’s CHT heating approach provides the largest adhesion gains at high flow/speed with an almost flat adhesion curve at 240°C.
- E3D vs TZ 3.0
- TZ 3.0 (with copper insert) shows little to no meaningful adhesion advantage over stock at lower temp.
- E3D maintains adhesion as throughput increases far more.
Pros / Cons (as reflected in the video)
E3D High-Flow ObXidian
Pros
- Much higher layer adhesion at high flow/speeds
- Near-flat adhesion curve at 240°C
- Matches the 60% flow improvement claim
- Design credited as the real reason performance is strong (CHT, split-flow heating)
Cons
- Not discussed as major drawbacks; the main “con” is framed more as an observation/measurement behavior (flattening explained), not a negative outcome.
Stock Bambu Lab hotend
Pros
- At 240°C, adhesion holds up well enough for higher speeds (up to ~200 mm/s described)
- Simpler/standard setup
Cons
- At 220°C, layer adhesion falls off rapidly with increased flow/speed
- Flow metrics can be misleading about adhesion performance
Bambu TZ 3.0
Pros
- Even “best case” testing (with the chosen copper insert + BN paste) performed poorly for adhesion
Cons
- Copper insert + hardened steel showed barely improved adhesion
- Needed 60W heater to reach target conditions at high flow; otherwise power/temperature constraints occur
- Cooling/heatsink interaction suspected
- Copper insert choice appears to be a bad idea for adhesion (except nickel-plated copper insert)
Overall verdict / recommendation
- Best recommendation: E3D High-Flow ObXidian (CHT design)
- Best for maximum layer adhesion at higher flow rates/speeds
- Delivers the most dramatic improvement and maintains adhesion far better than the others.
- Stock Bambu hotend: can work well if you print hotter (around 240°C), but it still loses adhesion as throughput increases—especially vs E3D.
- TZ 3.0: with the tested copper insert approach, it is not a strong adhesion performer in tensile testing; insert/nozzle material selection appears critical.
Unique points mentioned about the product(s) (consolidated)
- Layer adhesion testing via tensile strength machine (more reliable than max flow rate tests).
- Tested on Bambu P1S with stock heater/thermistor for fairness.
- Stock Bambu hotend: poor adhesion at 220°C, improved at 240°C.
- Stock hotend: flow/under-extrusion stats are misleading (3% under-extrusion can coincide with ~35% adhesion strength loss).
- E3D High-Flow ObXidian (CHT): dramatically better adhesion; adhesion curve flattens at high flow/speed.
- E3D claim of ~60% flow improvement aligns with results; focus is on adhesion, not flow alone.
- E3D likely improves because split-flow heating increases melt-zone effectiveness (faster heating/surface area).
- TZ 3.0: copper insert with BN paste yielded barely better adhesion at 240°C vs stock at 220°C.
- TZ 3.0: stock heater insufficient at high flow; needed 60W heater.
- TZ 3.0 adhesion reported around ~12 MPa in the cited comparison after fixes.
- Thermals/cooling interaction suspected (heatsink fan possibly reducing active melt zone).
- TZ 3.0 nozzle insert material conclusion: copper inserts generally hurt adhesion, except nickel-plated copper insert.
- Vertical print strength: consistent around ~67 MPa, with ~60% of original strength retained despite layer-by-layer construction.
- Thermistor location differences: measured with thermocouples on a TZ 2.0; idle temps same; small differences under heating/extrusion; potential up to ~5°C difference hypothesized with deeper measurement.
- Final guidance: don’t assume “plastic flows” means “good layer adhesion”; improve melt effectiveness (melt zone length / designs like CHT) rather than just cranking temperature.
Speakers
- Single primary speaker (reviewer/host) provides all test commentary and conclusions.
- Sponsor mention: PCBWAY (for machining holders) — not a separate technical viewpoint, just contribution/support.