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End-Grain Balsa Core SB.150

Grade

also 4088, Baltek

SB.150 = high density end-grain balsa, ~220 kg/m³

Highest-density grade for hard points, keel/engine bearers, blade root inserts and locally crushed zones.

High cost $$$$

Values for the SB.150 condition

Other End-Grain Balsa Core grades and fills

End-Grain Balsa Core is listed in 3 conditions; see the grade overview at End-Grain Balsa Core.

Compare all 3 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
Low density end-grain balsa, ~96 kg/m³
Lightest structural grade — pick for weight-critical decks, interior panels and non-highly-loaded blade panels.—91.2—
SB.100Default
Standard density end-grain balsa, ~150 kg/m³
The workhorse marine and wind-blade grade — best balance of compressive/shear capacity, resin uptake and cost.—131.1—
SB.150This page
High density end-grain balsa, ~220 kg/m³
Highest-density grade for hard points, keel/engine bearers, blade root inserts and locally crushed zones.—201—

What is End-Grain Balsa Core SB.150?

End-Grain Balsa Core SB.150 is End-Grain Balsa Core in the SB.150 grade — highest-density grade for hard points, keel/engine bearers, blade root inserts and locally crushed zones. End-Grain Balsa Core SB.150 has a tensile strength of 20 MPa (2.9 ksi), weaker than 82% of composite grades. Elongation at break is 1% and the elastic modulus is 6.2 GPa (0.899 Msi). End-Grain Balsa Core SB.150 has a density of 0.22 g/cm³ (0.0079 lb/in³), lighter than 83% of composite grades. SB.100 is the default condition FabDigit quotes; SB.150 is available on request or by drawing note.

Advantages

  • Low embodied carbon — 0.6 kg CO₂/kg, better than 99% of composite grades
  • Easy to machine — 88/100, better than 93% of composite grades
  • Lightweight — 0.22 g/cm³ (0.0079 lb/in³), better than 83% of composite grades

Limitations

  • Low fracture toughness — 0.18 MPa·√m (0.164 ksi·√in), worse than 98% of composite grades
  • Degrades in UV without stabilisers — 15/100, worse than 98% of composite grades
  • Needs corrosion protection — 42/100, worse than 94% of composite grades
  • Limited service temperature — 100°C (212 °F), worse than 92% of composite grades
  • Poor heat conductor — 0.07 W/m·K (0.0404 BTU/hr·ft·°F), worse than 81% of composite grades

End-Grain Balsa Core SB.150 properties

Typical room-temperature values for End-Grain Balsa Core SB.150; 15 are specific to this condition. Other listed values are End-Grain Balsa Core reference data and may not represent this condition. Bars are the position among composite grades.

Physical1

End-Grain Balsa Core SB.150 has a density of 0.22 g/cm³ (0.0079 lb/in³), lighter than 83% of composite grades.

Density0.22 g/cm³0.01 lb/in³

Mechanical8

End-Grain Balsa Core SB.150 has a tensile strength of 20 MPa (2.9 ksi), weaker than 82% of composite grades. Elongation at break is 1% and the elastic modulus is 6.2 GPa (0.899 Msi).

Elastic (Young's) Modulus6.2 GPa0.9 Msi
Shear Modulus0.21 GPa0.03 Msi
Tensile Strength (Ultimate)20 MPa2.9 ksi
Elongation at Break1%
Compressive Strength21 MPa3 ksi
Compressive Modulus6.2 GPa0.9 Msi
Shear Strength4 MPa0.62 ksi
Fracture Toughness (K_IC)0.18 MPa·√m0.16 ksi·√in

Thermal8

End-Grain Balsa Core SB.150 is rated for continuous service to 100°C (212 °F). It conducts heat at 0.07 W/m·K (0.0404 BTU/hr·ft·°F), worse than 81% of composite grades. Thermal expansion is 4 µm/m·K (2.22 µin/in·°F).

Thermal Conductivity0.07 W/m·K0.04 BTU/hr·ft·°F
Specific Heat Capacity1,600 J/kg·K0.38 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)4 µm/m·K2.2 µin/in·°F
Max Service Temperature (continuous)100°C212 °F
Min Service Temperature-196°C-321 °F
Flammability (UL 94)Not UL 94 rated — combustible natural wood; fire performance is set by the laminate skins and any FR resin/gelcoat
Limiting Oxygen Index22%
Max Service Temperature (short-term)163°C325 °F

Electrical1

End-Grain Balsa Core SB.150 has an electrical resistivity of 1×10⁹ Ω·m.

Electrical Resistivity1×10⁹ Ω·m3.94×10¹⁶ µΩ·in

Chemical & Environmental3

Corrosion resistance is fair (42/100), worse than 94% of composite grades. UV resistance is poor.

Corrosion ResistanceFair42/100
UV / Weathering ResistancePoor15/100
Chemical Resistance SummaryInert to styrene, epoxy, vinylester and polyester resins and to most solvents; hygroscopic — absorbs water and resin readily (uptake can add 0.5–2 kg/m² at the bond line), and is attacked by rot fungi, marine borers and freeze–thaw cycling once the skin is breached.

Sustainability3

Producing a kilogram of End-Grain Balsa Core SB.150 takes about 12 MJ of energy and emits 0.6 kg of CO₂ — less than 99% of composite grades. Typical recycled content is 0%.

Embodied Energy (primary production)12 MJ/kg5,159 BTU/lb
Embodied Carbon (primary production)0.6 kg CO₂/kg
Typical Recycled Content0%

Manufacturability1

End-Grain Balsa Core SB.150's machinability is excellent (88/100, better than 93% of composite grades).

MachinabilityExcellent88/100

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with End-Grain Balsa Core SB.150

Is End-Grain Balsa Core easy to machine?

Cuts and routs effortlessly with sharp carbide tooling or knife; use vacuum hold-down and dust extraction, and avoid crushing the end-grain cells when clamping.

Can End-Grain Balsa Core be welded?

Not applicable — panels are joined by scarf/butt bonding with thickened epoxy or by scrim-backed block joints.

Can End-Grain Balsa Core be formed, bent or molded?

Flat blocks for single curvature; contour-cut scrim-backed sheet drapes over compound curves; wet-out and grooves must be planned because balsa absorbs 0.5–2 kg/m² of resin at the bond faces.

What surface finishes work on End-Grain Balsa Core?

Seal all cut edges, fastener holes and skin penetrations with neat/thickened epoxy — unsealed core wicks water and rots; no painting or plating of the core itself.

End-Grain Balsa Core chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
cellulosestructural cell-wall polymer55 – 6560
hemicellulose15 – 2520
lignin12 – 2015
extractives + ash1 – 53
moisture (as supplied, kiln dried)typically specified ≤12 % for core stock6 – 129
adhesive (block edge-glue, PVA/urea)0.5 – 21

End-Grain Balsa Core SB.150 — frequently asked

What is End-Grain Balsa Core SB.150 used for?

End-Grain Balsa Core SB.150 is typically used for boat hulls and decks, wind turbine blade cores, rail car floors and aircraft interior panels. In short: highest compressive strength per weight; renewable natural core; must be fully sealed.

What is the tensile strength of End-Grain Balsa Core SB.150?

End-Grain Balsa Core SB.150 has a typical tensile strength of 20 MPa (2.9 ksi) — weaker than 82% of composite grades. Strength varies by condition: see the 3 listed tempers.

Is End-Grain Balsa Core SB.150 easy to machine?

Yes — machinability is rated excellent (88/100, better than 93% of composite grades). Cuts and routs effortlessly with sharp carbide tooling or knife; use vacuum hold-down and dust extraction, and avoid crushing the end-grain cells when clamping.

Can End-Grain Balsa Core SB.150 be welded?

Not applicable — panels are joined by scarf/butt bonding with thickened epoxy or by scrim-backed block joints.

What surface finishes work on End-Grain Balsa Core SB.150?

Seal all cut edges, fastener holes and skin penetrations with neat/thickened epoxy — unsealed core wicks water and rots; no painting or plating of the core itself.

Can End-Grain Balsa Core SB.150 be formed, bent or molded?

Flat blocks for single curvature; contour-cut scrim-backed sheet drapes over compound curves; wet-out and grooves must be planned because balsa absorbs 0.5–2 kg/m² of resin at the bond faces.

What is the maximum service temperature of End-Grain Balsa Core SB.150?

End-Grain Balsa Core SB.150 is rated for continuous use to about 100°C (212 °F), and briefly to 163°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. BALTEK SB / SBC end-grain balsa core data sheets — Airex AG / Gurit (2022)
  2. CoreLite / ProBalsa end-grain balsa core technical data — CoreLite Inc. / Grupo Rey (2021)
  3. ASTM C365 — Flatwise Compressive Properties of Sandwich Cores — ASTM (2016)
  4. ASTM C273 — Shear Properties of Sandwich Core Materials — ASTM (2020)
  5. Wood Handbook — Wood as an Engineering Material (FPL-GTR-282) — USDA Forest Products Laboratory (2021)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.