Note:
Stiff ness of nut:
Stiff ness values listed above are derived from theoretical formula to the elastic deformation between thread grooves and balls while axial load is
30% dynamic load rating.

Unit:mm
Screw size Ball DIA.

Effeftive turns
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 BASIC RATE LOAD(kgf) BALLNUT DIMENSION Nut Model No.
O.D. Length Flange Assembly
Hole		 Oil Hole STIFFNESS
O.D. Lead Dynamic
(1×106 REV.)
Ca

Static

Co

 D

L

 A T W G H X Y Z Q kgf/μm
14 4 2.381 4 400 890 26 47 46 10 36 20 40 4.5 8 4.5 M6x1P 19 FSIW1404A-4.0P
16 4 2.381 3 320 760 28 42 48.5 10 39 20 40 4.5 8 4.5 M6x1P 13 FSIW1604A-3.0P
5 3.175 3 570 1030 30 42 49 10 39 20 40 4.5 8 4.5 M6x1P 17 FSIW1605B-3.0P
20 4 2.381 4 450 1270 34 44 60 12 48 22 44 5.5 9.5 5.5 M6x1P 19 FSIW2004A-4.0P
5 3.175 4 830 1890 34 53 57 12 45 20 40 5.5 9.5 5.5 M6x1P 21 FSIW2005B-4.0P
25 4 2.381 3 380 1195 40 40 63 12 51 22 44 5.5 9.5 5.5 M8x1P 17 FSIW2504A-3.0P
5 3.175 4 940 2420 40 53 63.5 12 51 22 44 5.5 9.5 5.5 M8x1P 26 FSIW2505B-4.0P
10 4.762 4 1550 3540 42 85 68.5 15 55 26 52 6.6 11 6.5 M8x1P 28 FSIW2510D-4.0P
28 6 3.175 3 770 2180 43 50 68 12 55 26 52 6.6 11 6.5 M8x1P 22 FSIW2806B-3.0P
32 5 3.175 4 1050 3390 48 53 73.5 12 60 30 60 6.6 11 6.5 M8x1P 32 FSIW3205B-4.0P
10 6.35 4 2510 5880 54 90 88 16 70 34 68 9 14 8.5 M8x1P< 34 FSIW3210F-4.0P
36 10 6.35 4 2570 6870 58 89 98 18 77 36 72 11 17.5 11 M8x1P 39 FSIW3610F-4.0P
40 5 3.175 4 1180 4390 55 56 88.5 16 72 29 58 15 9 14 M8x1P 38 FSIW4005B-4.0P
10 6.35 4 2630 7860 64 93 106 18 84 43 86 11 17.5 11 M8x1P 41 FSIW4010F-4.0P
50 10 6.35 4 2770 10290 74 93 116 18 94 42 84 11 17.5 11 M8x1P 50 FSIW5010F-4.0P
63 10 6.35 4 3760 13700 85 98 132 22 107 48 96 14 20 13 M8x1P 60 FSIW6310F-4.0P
80 10 6.35 4 4130 17660 105 98 151 22 127 57 114 14 20 13 M8x1P 73 FSIW8010F-4.0P