With six sided heads, Hex bolts boast of being the industry standard as far as fasteners with forged heads are concerned. ASTM A307 grade A bolts, SAE hex bolts, and numerous other common specifications demand a standard hex head. When it comes to specifications like A307 grade B, A325 & A490 which demand a heavy hex pattern, it is ideal to refer dimensional tolerances for structural bolts or heavy hex bolts.

Applications

Hex bolts are primarily used for fastening steel, wood and various other construction materials with regards to projects including bridges, docks, buildings and highway structures. Hex bolts that come with forged heads are generally used as headed anchor bolts as well.

Manufacturing

Baseline Bolt manufactures high quality hex bolts of diameter 1/2″ - 2-1/2″ fulfilling most of the ASTM, AASHTO & SAE specifications. What’s more, it is possible to create special tooling so as to produce nonstandard head dimensions / bolt heads with the name and/or logo of your company or business.

Stock

Diameters: 1/2 – 1″
Grade: ASTM A307, F1554 Grade 36
Lengths: 30″ maximum
Origin: Domestic and import
Finish: Plain and hot dip galvanized

Standard Thread Length

Bolt lengths ≤ 6″: Thread length = (2 X diameter) + 1/4″
Bolt lengths > 6″: Thread length = (2 X diameter) + 1/2″
Note: Most stock hex bolts 10″ and longer will have 6″ of thread.

Hex Bolt Dimensions

Click to show drawing
Bolt Diameter D F C H
Body Diameter Width Across Flats Width Across Corners Height
Max Basic Max Min Max Min Basic Max Min
1⁄2 0.515 3⁄4 0.750 0.725 0.866 0.826 11⁄32 0.364 0.302
5⁄8 0.642 15⁄16 0.938 0.906 1.083 1.033 27⁄64 0.444 0.378
3⁄4 0.768 11⁄8 1.125 1.088 1.299 1.240 1⁄2 0.524 0.455
7⁄8 0.895 15⁄16 1.312 1.269 1.516 1.447 37⁄64 0.604 0.531
1 1.022 11⁄2 1.500 1.450 1.732 1.653 43⁄64 0.700 0.591
11⁄8 1.149 111⁄16 1.688 1.631 1.949 1.859 3⁄4 0.780 0.658
11⁄4 1.277 17⁄8 1.875 1.812 2.165 2.066 27⁄32 0.876 0.749
13⁄8 1.404 21⁄16 2.062 1.994 2.382 2.273 29⁄32 0.940 0.810
11⁄2 1.531 21⁄4 2.250 2.175 2.598 2.480 1 1.036 0.902
15⁄8 1.658 27⁄16 2.438 2.356 2.815 2.616 13⁄32 1.116 0.978
13⁄4 1.785 2-5/8 2.625 2.538 3.031 2.893 15⁄32 1.196 1.054
17⁄8 1.912 213⁄16 2.812 2.719 3.248 3.099 11⁄4 1.276 1.130
2 2.039 3 3.000 2.900 3.464 3.306 111⁄32 1.388 1.175
21⁄4 2.305 33⁄8 3.375 3.262 3.897 3.719 11⁄2 1.548 1.327
21⁄2 2.559 33⁄4 3.750 3.625 4.330 4.133 121⁄32 1.708 1.479
Dimensions per ASME B18.2.1 2010

Stock Domestic Hex Bolts

Length Diameter
1/2" 5/8" 3/4" 7/8" 1"
Plain Galv. Plain Galv. Plain Galv. Plain Galv. Plain Galv.
8 - 17490 - 17997 18035 18036 - - - -
10 - 17492 - 17999 18007 18008 - - - -
12 - 17494 1800 18001 18009 18010 - - - -
14 - - - - 18013 18014 - - 18051 -
16 - - - - 18017 18018 - 18040 - 18054
18 - 17496 18002 18003 18021 18022 18045 18041 18055 18056
20 - - - - 18023 18024 - 18042 - 18058
22 - - - - - 18026 - - - -
24 - - - 18005 18027 18028 18047 18043 18061 18062
26 - - - - 18029 18030 - - - -
30 - - - - - 18034 - 18045 18871 18872
36 - - - - - - - - 18876 18877
These hex bolts meet the requirements of both F1554 Grade 36 and A307 Grade A.
Other sizes and finishes available on request.

Stock Import Hex Bolts

Length (in.) Diameter
1/2" 5/8" 3/4" 7/8" 1"
Plain Galv. Plain Galv. Plain Galv. Plain Galv. Plain Galv.
1 10235 10236 - - 10477 10478 - - - -
11⁄2 10239 10240 10339 10340 - - - - - -
2 10243 10244 10343 10344 10481 10482 10619 10620 10729 10730
21⁄2 10247 10248 10347 10348 - - 10623 10624 10733 10734
3 10251 10252 10351 10352 10489 10490 10627 10628 10737 10738
31⁄2 10253 10254 10355 10356 10493 10494 10631 10632 10741 10742
4 10255 10256 10354 10360 10497 10498 10635 10636 10745 10746
41⁄2 10257 10258 10361 10362 10499 10500 10639 10640 10749 10750
5 10259 10260 10363 10364 10501 10502 10641 10642 10751 10752
51⁄2 10261 10270 10365 10366 10503 10504 - - 10753 10754
6 10263 10264 10367 10368 10505 10506 10645 10646 10755 10756
61⁄2 10265 10266 10369 10370 10507 10508 10647 10648 10757 10758
7 10267 10268 10371 10372 10509 10510 10649 10650 10759 10760
71⁄2 10269 10270 10373 10374 10511 10512 10651 10652 10761 10762
8 10271 10272 10375 10376 10513 10514 10653 10654 10763 10764
81⁄2 10273 10274 10377 10378 10515 10516 - - 10765 10766
9 10275 10276 10379 10380 10517 10518 10657 10658 10767 10768
10 10279 10280 10383 10384 18320 18321 18328 18329 18805 18806
11 10283 10284 10387 10388 18324 18325 19489 19490 18809 18810
12 10287 10288 18310 18311 18326 18327 18799 18800 18811 18812
13 10295 18772 18822 18823 18409 19223 18850 18851 19250 19251
14 10295 10296 18312 18313 19227 19228 19246 19247 19252 19253
15 18193 18194 18824 18825 19229 19230 18852 18553 19256 19157
16 18773 18774 18314 18315 18410 19231 19248 19249 19254 19255
18 18777 18778 18316 18317 19234 19235 18854 18855 19260 19261
20 18781 18782 18318 18319 19238 19239 18857 18858 19262 19263
24 19503 - 18833 18834 19244 19245 18862 18863 - -
These sizes are readily available in the marketplace and Baseline Bolt stocks many of them in varying quantities. If you require a size that is not listed, Baseline Bolt will manufacture them.