Deflection Charts

Below we have listed physical properties for both our E-Glass/Epoxy and Carbon/Epoxy battens.

At the bottom of the chart there is a brief discussion on the EI numbers, how we derived them and how they can help you in proper and exact batten selection for your sails.

PLEASE CLICK ON EACH TAB FOR INFO!

E-Glass / Epoxy
E-Glass Epoxy
– Non Tapered -
RBS Battens Flexural Stiffness Flexural Stiffness 3 Point Deflection Weight per Meter Available Lengths
Order Code Spring Rate Beam Theory, E.I 10 Lbs – 1 m
Lbs/Inches NM^2 Inches mm Grams mm
E38540 78.12 285.1 0.128 3.3 1048 10660
E25500 41.67 152.1 0.240 6.1 592 9144
E25400 21.74 79.4 0.460 11.7 485 9144
E25350 15.04 54.9 0.665 16.9 424 6100
E25300 9.35 34.1 1.070 27.2 362 6100
E25265 6.72 24.5 1.488 37.8 323 6100
E19400 16.53 60.3 0.605 15.4 364 6100
E19350 11.48 41.9 0.871 22.1 320 6100
E19300 7.12 26.0 1.405 35.7 275 6100
E19265 4.90 17.9 2.040 51.8 239 6100
E19230 3.13 11.4 3.200 81.3 206 6100
E19200 2.31 8.4 * 2.160 54.9 185 6100
E19180 1.65 6.0 * 3.030 77.0 167 6100
E19160 1.26 4.6 ** 1.780 45.2 148 6100
E15300 5.79 21.1 1.728 43.9 215 6100
E15265 4.03 14.7 2.480 63.0 192 6100
E15230 2.67 9.7 3.750 95.3 165 6100
E15200 1.81 7.4 * 2.763 70.2 148 6100
E15180 1.31 4.8 ** 1.715 43.6 130 6100
E15160 0.95 3.5 ** 2.34 59.4 117 6100
E15140 0.58 2.1 *** 1.605 40.8 98 6100
E10300 3.99 14.6 ** 0.562 14.3 146 6100
E10265 2.65 9.7 ** 0.848 21.5 127 6100
E10230 1.85 6.8 ** 1.211 30.8 110 6100
E10200 1.18 4.3 ** 1.898 48.2 95 6100
E10180 0.86 3.1 ** 2.595 65.9 85 6100
E10160 0.62 2.3 *** 1.495 38.0 75 6100
E10140 0.46 1.7 *** 2.018 51.3 67 6100
E10120 0.33 1.2 **** 0.700 17.8 56 6100
E10100 0.26 0.9 **** 0.910 23.1 48 4191
E10090 0.23 0.8 **** 1.000 25.4 44 4191
* 5 lbs / 2.27 Kg weight used
** 2.244 lbs / 1.019 Kg weight used
*** 0.933 lbs/ 0.423 Kg weight used
**** 0.234 lbs / 0.106 Kg weight used
Carbon Epoxy
Carbon/Epoxy
–Non Tapered–
RBS Battens Flexural Stiffness Flexural Stiffness 3 Point Deflection Weight per Meter Available Lengths
Order Code Spring Rate Beam Theory, E.I 10 Lbs – 1 m
Lbs/Inches NM^2 Inches mm Grams mm
CB38400 105.26 384.21 0.095 2.4 588 9100
CB38350 70.42 257.04 0.142 3.6 507 9100
CB38300 43.86 160.09 0.228 5.8 438 9100
CB38250 24.39 89.02 0.410 10.4 365 9100
CB25400 66.67 243.33 0.150 3.8 382 6010
CB25350 43.29 158.01 0.231 5.9 329 6010
CB25300 27.03 98.65 0.370 9.4 284 6010
CB25250 15.36 56.07 0.651 16.5 240 6010
CB19400 50.76 185.28 0.197 5.0 292 6010
CB19350 33.44 122.07 0.299 7.6 253 6010
CB19300 21.74 79.35 0.460 11.7 218 6010
CB19250 11.64 42.49 0.859 21.8 182 6010
CB19200 6.88 25.12 1.453 36.9 151 6010
CB15300 14.90 54.40 0.671 17.0 168 6010
CB15250 9.80 35.78 1.020 25.9 150 6010
CB15200 5.43 19.84 1.840 46.7 122 6010
CB10250 6.51 23.76 1.536 39.0 98 6010
CB10200 3.35 12.23 *1.492 37.9 79 6010
CB10150 1.54 5.63 **1.455 37.0 61 6010
CB10120 0.78 2.85 **2.870 72.8 47 6010
* 5 lbs / 2.27 Kg weight used
** 2.244 lbs / 1.019 Kg weight used
Carbon Equivalent

Carbon Equivalent Charts

Click here for a Printable PDF of this RBS Batten Carbon Equivalent Chart

E-GLASS TO CARBON SUGGESTED/CLOSEST STIFFNESS EQUIVALENT
WEIGHT E-GLASS STIFFNESS STIFFNESS SUGGESTED
CARBON
EQUIVALENT
WEIGHT
44 E10090 0.8**** n/a n/a n/a
48 E10100 0.9**** n/a n/a n/a
56 E10120 1.2**** n/a n/a n/a
67 E10140 1.7*** n/a n/a n/a
75 E10160 2.3*** n/a n/a n/a
85 E10180 3.1** = 2.85** CB10120 47
95 E10200 4.3** = 5.63** CB10150 61
110 E10230 6.8** = 5.63** CB10150 61
127 E10265 9.7** = 12.23* CB10200 79
146 E10300 14.6** = 12.23* CB10200 79
29 E12050 n/a n/a n/a n/a
35 E12060 n/a n/a n/a n/a
41 E12070 n/a n/a n/a n/a
53 E12090 n/a n/a n/a n/a
98 E15140 2.1*** n/a n/a n/a
117 E15160 3.5** = 2.85** CB10120 47
130 E15180 4.8** = 5.63** CB10150 61
148 E15200 7.4* = 12.23* CB10200 79
165 E15230 9.7 = 12.23* CB10200 79
192 E15265 14.7 = 19.84 CB15200 122
215 E15300 21.1 = 19.84 CB15200 122
148 E19160 4.6** n/a n/a n/a
167 E19180 6* n/a n/a n/a
185 E19200 8.4* = 14.68* CB15150 92
206 E19230 11.4 = 19.84 CB15200 122
239 E19265 17.9 = 25.12 CB19200 151
275 E19300 26 = 25.12 CB19200 151
320 E19350 41.9 = 42.49 CB19250 182
364 E19400 60.3 = 79.35 CB19300 218
323 E25265 24.5 = 25.12 CB19200 151
362 E25300 34.1 = 42.49 CB19250 182
424 E25350 54.9 = 56.07 CB25250 240
485 E25400 79.4 = 98.65 CB25300 284
592 E25500 152.1 = 158.01 CB25350 329
1048 E38540 285.1 = 384.21 CB38400 588

Batten material properties above are explained in terms of weight and stiffness.

  • For weight (or mass) we use grams. (One gram equals 0.0022 lb., 1000 g or 1 Kg = 2.205 lb.)
  • For stiffness we use two expressions; Spring Rate and EI-Beam Theory numbers.
Battens are used to stabilize sail shape, and are used primarily for their rigidity or stiffness.
“Spring Rate” numbers and “EI” numbers are values used to quantify this flexural rigidity or bending stiffness property of a batten due to the material properties combined with the geometry or shape and size of the batten.
“Spring Rate” is the ratio of the weight in lb. over the deflection in inches using a constant beam span (1 m). For the same beam geometry, and when using a constant beam span of 1 meter, the correlation factor between Spring Rate and EI is 3.65 (EI = 3.65 X SR).
SR = Bending stiffness (ratio weight over deflection) (lbs/inches)
According to Beam Theory, the bending stiffness of a beam, E.I, is defined as the product of the modulus of elasticity (E) (also called Young’s Modulus) and the moment of inertia (I) (also called mass moment of inertia). Metric units are in kilograms and meters (Kgf = 9.807 N)
E = E-modulus (N/m^2 = Pa)
I = Moment of inertia (m^4)
EI = Bending stiffness (product of E and I) (Nm^2) (or more commonly Nm^2)

EI-Beam Theory values were all measured and calculated using standard engineering calculations that give a bending stiffness value in Nm^2. The deflection (d) is measured at the center of the beam length, and is related as d = PL^3/48IE. We note that it is proportional to the load P, to the cube of the span L, and inversely proportional to the flexural rigidity IE. Solving for EI = PL^3/48d. For this calculation, any span and load can be used, making sure that the deflection doesn’t excessively sag the batten and change the measured length of the batten.

Feel free to email us with any questions or discussions.

Most of the deflections were measured using a 10 lb. weight for the deflection. Values preceded with a “*” were measured at the lower weights indicated, yielding higher accuracy.
PS>
Visco-elastic properties affecting dynamic batten response are not reflected by the E.I values, as they are more material property related (E-Glass, Carbon, Epoxy, interfacial adhesion, …)