Calculation of rpm and pressure to spin weld

[Adaware]

Let's say i want to spin weld to parts of the same diameter and material.

How can i calculate the initial axialpressure and the rpm needed to get e good spid weld?
Is it just trial and error or is there some tools to get it "just about" the first time?

 

[hydtools]

Here is a start:

http://www.swansonindustries.com/inertiawelding.php

Ted

 

[hydtools]

Another reference:

http://www.aws.org/wj/supplement/wj0708-178.pdf

Ted

 

[chicopee]

Since all the welding techniques to which I have been exposed to involved oxy-acetylene, MIG and TIG, I find this welding process fascinating.