Quote Originally Posted by HipoPapi View Post
This hopefully gives you a better idea of what forces are needed for Ice
To be honest I would imagine the forces are a bit less than cutting soft woods so your design is well upto the job.
Personally given your relatively light needs then I would use HD Aluminium profile for the gantry beams and make life very easy for your self. The profile makes fitting rails very easy and accurate, if combined with Aluminium plate for the gantry sides that is manipulated in a certain way then it's very accurate and strong.
Steel is great when mass strength is needed but there is alot of work involved in building with it and getting accurecy. The combination of steel for the base for cost saving and strength but with the ease of building an accurate but still strong gantry with profile/plate is the route I would be taking.