FAQs Roller Measurement-Axle

FAQs Part 4: Measuring the Conveyor Roller Axle

To Begin: Please fill out our Conveyor Roller Quote Form and a Heinrich Brothers representative will contact you.
For more immediate help, call us at 724-969-1188.

How do I Measure Roller Axle Length?

Place angles or straight edges against the ends of the axle. Use a tape measure to measure between the angles. Measure to the nearest 1/32″.


How do I Measure Conveyor Roller Axle Extensions?

Use the tape measure to measure from the front face of each bearing to the end of the axle. Measure to the nearest 1/32″. This must be done for both sides of the roller as the axle extension might be different on each side.


How do I Measure Roller Axle Size?

You must use Calipers to measure the axle size. Measure to the nearest 0.001″. For round axles,measure the diameter. For hex axles,measure the distance across the flats.


Use our Fractions to Decimals Conversion Chart to convert fractions of an inch to decimals to assist in converting axle size measurements.

How do I Determine Roller Axle Material?

Steel Axles: Use a magnet on the axle to identify if the material is steel. If the axle is magnetic is is steel. High quality 420 Stainless Steel can sometimes have magnetic properties but this is not a common stainless steel grade used to make roller axles. Keep in mind we do not provide axles in aluminum or galvanized steel.

Stainless Steel Axles: Stainless Steel has a bright,silver,usually smooth finish. Most stainless tube will have a weld seam.

What is Axle Machining?

Identify if the axle has been machined. Use the calipers to measure any of the machined dimensions. Measure to the nearest 0.001″.

Tip: Draw the dimensions at the same time as taking the measurements to ensure every dimension is recorded. It is critical to record every dimension to measure the axle correctly. In addition to the dimensions of the axle,measure from the end of the axle to the machined feature.

Reference the drawing below to identify some common machining options:


How do I Measure Drilled and Tapped or Threaded Axles?

You must use a thread gauge to match the pitch of the screw heads (screw pitch)

The thread gauge contains two sets of gauges,metric and English.

-The metric gauges are labeled .5 through 6 threads per millimeter,all decimals.

-The English gauges are labeled 4 through 56 threads per inch,all whole numbers.

Use the appropriate set of thread blades to measure the screw pitch.


You must use the calipers to measure the outer diameter of the bolt for a drilled and tapped axle or the machined section of the threaded axle to determine if it is metric or English. Using a Metric Conversion Chart,find the closest measurement. Measure to the nearest .001″. If a bolt is not included with the drilled and tapped axle use the calipers to measure the inner diameter of the machined axle. Use the thread gauge measurement to match the numbers to the right of the hyphen of the tap size.

Example: Thread gauge measurement is 1.25mm.

Use the outer diameter measurement to match the numbers to the left of the hyphen of the tap size.

Example: OD is .385″,converts to approximately 10mm

The two numbers combined 10 & 1.25 match up with the tap size M10-1.25.

If the measurements do not match exactly find the closest one to give a general size.