End-Grain Balsa Core SB.50
Grade
also 4088, Baltek
SB.50 = low density end-grain balsa, ~96 kg/m³
Lightest structural grade — pick for weight-critical decks, interior panels and non-highly-loaded blade panels.
Values for the SB.50 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 datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
SB.50This page Low density end-grain balsa, ~96 kg/m³ | Lightest structural grade — pick for weight-critical decks, interior panels and non-highly-loaded blade panels. | — | 9 | 1.2 | — |
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. | — | 13 | 1.1 | — |
High density end-grain balsa, ~220 kg/m³ | Highest-density grade for hard points, keel/engine bearers, blade root inserts and locally crushed zones. | — | 20 | 1 | — |
What is End-Grain Balsa Core SB.50?
End-Grain Balsa Core SB.50 is End-Grain Balsa Core in the SB.50 grade — lightest structural grade — pick for weight-critical decks, interior panels and non-highly-loaded blade panels. End-Grain Balsa Core SB.50 has a tensile strength of 9 MPa (1.28 ksi), weaker than 84% of composite grades. Elongation at break is 1.2% and the elastic modulus is 2.5 GPa (0.363 Msi). End-Grain Balsa Core SB.50 has a density of 0.1 g/cm³ (0.0035 lb/in³), lighter than 87% of composite grades. SB.100 is the default condition FabDigit quotes; SB.50 is available on request or by drawing note.
Advantages
- Easy to machine — 95/100, better than 101% of composite grades
- Low embodied carbon — 0.6 kg CO₂/kg, better than 99% of composite grades
- Lightweight — 0.1 g/cm³ (0.0035 lb/in³), better than 87% of composite grades
Limitations
- Low fracture toughness — 0.12 MPa·√m (0.109 ksi·√in), worse than 100% of composite grades
- Degrades in UV without stabilisers — 15/100, worse than 98% of composite grades
- Needs corrosion protection — 40/100, worse than 96% of composite grades
- Limited service temperature — 100°C (212 °F), worse than 92% of composite grades
- Poor heat conductor — 0.05 W/m·K (0.0277 BTU/hr·ft·°F), worse than 90% of composite grades
End-Grain Balsa Core SB.50 properties
Typical room-temperature values for End-Grain Balsa Core SB.50; 14 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.50 has a density of 0.1 g/cm³ (0.0035 lb/in³), lighter than 87% of composite grades.
Mechanical8
End-Grain Balsa Core SB.50 has a tensile strength of 9 MPa (1.28 ksi), weaker than 84% of composite grades. Elongation at break is 1.2% and the elastic modulus is 2.5 GPa (0.363 Msi).
Thermal8
End-Grain Balsa Core SB.50 is rated for continuous service to 100°C (212 °F). It conducts heat at 0.05 W/m·K (0.0277 BTU/hr·ft·°F), worse than 90% of composite grades. Thermal expansion is 4 µm/m·K (2.22 µin/in·°F).
Electrical1
End-Grain Balsa Core SB.50 has an electrical resistivity of 1×10⁹ Ω·m.
Chemical & Environmental3
Corrosion resistance is fair (40/100), worse than 96% of composite grades. UV resistance is poor.
Sustainability3
Producing a kilogram of End-Grain Balsa Core SB.50 takes about 12 MJ of energy and emits 0.6 kg of CO₂ — less than 99% of composite grades. Typical recycled content is 0%.
Manufacturability1
End-Grain Balsa Core SB.50's machinability is excellent (95/100, better than 101% of composite grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with End-Grain Balsa Core SB.50
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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| cellulosestructural cell-wall polymer | 55 – 65 | 60 |
| hemicellulose | 15 – 25 | 20 |
| lignin | 12 – 20 | 15 |
| extractives + ash | 1 – 5 | 3 |
| moisture (as supplied, kiln dried)typically specified ≤12 % for core stock | 6 – 12 | 9 |
| adhesive (block edge-glue, PVA/urea) | 0.5 – 2 | 1 |
End-Grain Balsa Core SB.50 — frequently asked
What is End-Grain Balsa Core SB.50 used for?
End-Grain Balsa Core SB.50 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.50?
End-Grain Balsa Core SB.50 has a typical tensile strength of 9 MPa (1.28 ksi) — weaker than 84% of composite grades. Strength varies by condition: see the 3 listed tempers.
Is End-Grain Balsa Core SB.50 easy to machine?
Yes — machinability is rated excellent (95/100, better than 101% 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.50 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.50?
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.50 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.50?
End-Grain Balsa Core SB.50 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
- BALTEK SB / SBC end-grain balsa core data sheets — Airex AG / Gurit (2022)
- CoreLite / ProBalsa end-grain balsa core technical data — CoreLite Inc. / Grupo Rey (2021)
- ASTM C365 — Flatwise Compressive Properties of Sandwich Cores — ASTM (2016)
- ASTM C273 — Shear Properties of Sandwich Core Materials — ASTM (2020)
- 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.