Technical Questions

Do you have a chart to help us troubleshoot bad bends?
Yes. You can download our Troubleshooting Bad Bends document to help you troubleshoot issues.


How do I assemble or disassemble a mandrel?
Read the Mandrel Assembly Instructions document for guidance.


How much material is removed on a wiper die recut?
Click here to see how complex wipers are affected.
Click here to see how simple wipers are affected.


I am bending stainless steel. What material should the mandrel and wiper die be made of?
When bending stainless steel, the mandrel and wiper die should always be made from Aluminum Bronze.


What is the difference between standard and interlock tooling?
Interlock means that the clamp and pressure dies are locked together vertically with the bend die. This ensures that the tube grooves are aligned to reduce tool marking on the tube. Interlocked tooling is highly recommended on all difficult applications where the wall factor is above forty. Interlock tooling is also simpler to setup because it either fits together correctly or not at all.
Standard tooling is more economical and can achieve desired results when setup properly on less difficult bends. It also has an advantage when the tube diameter approaches the capacity of the machine, the interlocking tabs get very thin. This increases the likelihood of the tabs breaking.


SurfAlloy™ is a special process for applying a coating, generally carbide, to the working area of a bend die insert and clamp die to prevent the tube from slipping during bending.


What is the proper setup location for a mandrel?
The tangent setting for a mandrel can vary greatly depending on the tube outside diameter and the style of the mandrel you are using. You can refer to the chart here to determine how far forward the mandrel should be beyond the tangent.


Mandrels and wipers should be made out of which materials?
In general, when bending non-ferrous materials, such as stainless steel, you should use mandrels and wipers made out of aluminum bronze.
When bending ferrous materials, such as mild stell and aluminum, a chrome plated mandrel and wiper die should be used. Other factors may also play a role in the type of surface coating to be applied to a mandrel or wiper die.
Please contact us for more information on the latest coating technologies.


What rotation is my bender?
The rotation of your bender refers to the rotation of the swing arm during rotary draw bending. The rotation will either be a left-hand rotation (counter-clockwise) or a right hand rotation (clockwise).
Looking at the machines from the top, with the swing arm in a closed position (prior to bending), begin the bending cycle. Which way is the arm moving? Clockwise or counter-clockwise? That is the rotation of your bender.


What tools do I need for bending?
To successfully execute rotary draw bending, you will need a bend die, clamp die, and pressure die, at a minimum. A mandrel and wiper may also be required, depending on the tube outside diameter, wall thickness, and the centerline radius of the bend.