Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Nails and Spikes - Withdrawal Force

Allowable withdrawal load for nail and spikes.

Allowable withdrawal load or force for a common nail or spike driven into side grain perpendicular to the fibers of seasoned wood (or wet unseasoned wood) can be estimated as

F = 1380 SG5/2 D                       (1)

where

F = allowable withdrawal load or force per inch of penetration (lb/in)

SG = specific gravity of oven dry wood

D = diameter of nail or spike (inches)

Note that the allowable load is 1/5 of the ultimate withdrawal resistance (USDA document FPL-0100).

Example - Nail Withdrawal Load

The specific gravity of Canadian Spruce is 0.45. The diameter of 20D nail is 0.203 inches. The allowable withdrawal force per inch of penetration can be estimated as

F = 1380 (0.45)5/2 (0.203 in)

   =  38 lb/in (lb per inch penetration)  

spike nail

Nail Withdrawal Force Calculator

Imperial Units

Metric Units

Allowable Withdrawal Forces for some Common US Wire Nails

- for Spruce with specific gravity 0.5

Nails and Spikes - Withdrawal Force - US Wire Nails
SizeLength
(in)
Allowable Withdrawal Force
(lb)
2d 1 17.6
3d 25.3
4d 39.9
5d 46.5
6d 2 58.5
8d 81.7
10d 3 108
12d 117
16d 141
20d 4 198
30d 242
40d 5 290
60d 6 348

Allowable Withdrawal Forces for some Common Metric  Wire Nails

- for Spruce with specific gravity 0.5

Nails and Spikes - Withdrawal Forcecaption - Metric  Wire Nails
Length
(mm)
Diameter
(mm)
Allowable Withdrawal Force
(N)
20 1.2 40.4 (4.12 kg)
25 1.4 58.9 (6 kg)
30 1.6 80.8 (8.23 kg)
35 1.6 94.2 (9.61 kg)
35 1.8 106 (10.8 kg)
40 2.0 135 (13.7 kg)
45 2.2 167 (17 kg)
50 2.2 185 (18.9 kg)
55 2.2 204 (20.8 kg)
55 2.5 231 (23.6 kg)
60 2.5 252 (25.7 kg)
60 2.8 283 (28.8 kg)
65 2.8 306 (31.2 kg)
65 3.1 339 (34.6 kg)
70 3.1 365 (37.2 kg)
80 3.1 417 (42.5 kg)
80 3.4 458 (46.7 kg)
90 3.4 515 (52.5 kg)
90 3.8 575 (58.7 kg)
100 3.8 639 (65.2 kg)
100 4.2 707 (72 kg)

Metric Nails Withdrawal Force Chart

Download and print Metric Nails Withdrawal Force Chart

3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Unit Converter


















































6.6.11

.