Nate's FAQs

Standard Flat Washer

F436 vs F844

Are you allowed to substitute F436 hard washers when F844 cut washers are called out?

In general substituting one grade of fastener for another is a bad idea, as that substitution can open you up to liability concerns, but does this apply to washers? ASTM F844 covers standard, unhardened steel washers for general use. ASTM F436 covers hardened steel washers used with most high strength bolts and F1554 anchor bolts. F844 is... Read more


My plans specify A36M55. Is that a bolt grade?

A36M55 is an outdated call out for anchor bolts primarily used by the light pole and traffic signal industries. It was used to specify ASTM A36 steel (36 ksi yield strength) that had been chemically modified to develop a minimum 55 ksi yield strength. In 1994 the F1554 specification was introduced, and F1554 Grade 55... Read more


Why does Portland Bolt need me to provide a take-off for a specific project?

A take-off is a list of all the materials required to build a project based on the supplied plans. For example, if you had plans for building a dock, the plans might show a typical section of dock and you would use that to extrapolate how many board feet of timber and how many bolts... Read more

Bolt Blanks

What is a Bolt Blank?

From time to time our friendly estimators may mention that we are going to make your order using bolt blanks.  But what is a bolt blank? In order to help facilitate small runs of custom bolts and rush orders, Portland Bolt stocks bolt blanks. Bolt blanks are headed bolts that have not been threaded yet.... Read more

Fully Threaded ASTM A325

A325T Thread Length

How close to the underside of the head do A325T threads need to be?

Under the new F3125 and original A325 specification, fully threaded structural bolts are allowable if the length of the bolt does not exceed 4 times the diameter (for more information please refer to our article: What is an A325T bolt?). We recently had a customer ask about how close the threads need to be to... Read more


Clevis & Turnbuckle Grades

What grade are Portland Bolt’s Clevises and Turnbuckles?

For most tie rod assemblies that Portland Bolt provides, the clevises would be forged per ASTM A668 Class A, while the turnbuckles would be forged per ASTM A668 Class C. ASTM A668 is a general forging specification. An additional ASTM specification F1145 also covers turnbuckles specifically. If higher strength clevises are required to develop the strength... Read more

Shear Plate Dimensions

What are the physical dimensions of a shear plate?

The physical dimensions of shear plates are governed by ASTM D5933. Shear plates come in two sizes, 2-5/8” outside diameter and 4” outside diameter. In several cases, we have been asked the dimensions of everything other than the OD and bolt hole. All of those dimensions are listed in the diagrams below. If your project requires... Read more

Special A325 Bolts

Why are the heads of my A325 bolts marked with the letter “S”?

Under the new F3125 specification, which now governs A325 structural bolts, there is a supplementary requirement that allows A325 bolts to differ in head geometry and thread length (excluding fully threaded A325s) as required by the customer. When these alternate dimensions are required, the bolts shall be stamped “A325S”, with the “S” indicating special. Under the... Read more

Crane mat

Crane Mat Rods

Does Portland Bolt manufacture crane mat rods and bolts?

Yes, Portland Bolt manufactures crane mat rods. Crane mats (also known as timber mats, barge mats, road mats, swamp mats, pipeline mats, and floater mats) are wooden mats used for stabilizing machinery (often cranes) on unstable ground. They can also be used as a makeshift road, similar to a corduroy road. Crane mat rods are long threaded... Read more

B7 Length Tolerance

What is the length tolerance on ASTM A193 Grade B7 bolts?

The tolerances for A193-B7 are governed by section 4 of the specification, which states, “Material and fasteners supplied to this specification shall conform to the requirements of Specification A 962/A 962M. These requirements include test methods, finish, thread dimensions, marking, certification, optional supplementary requirements, and others.”   Studs (also known as All Thread Rods) would be... Read more