Hi All,

I am getting into fairly complex casting and pattern work - currently working out the bugs of a 4 cylinder head for a car http://www.cnczone.com/forums/castin...ml#post1888208

I have been using Alibre for all my CAD work. Its got me by mostly but I can't do non-planar parting lines, and it can't really do surface modeling. I used Blender and did some mesh modeling for some patterns but its too time consuming and mesh models are not the best for machining. I have played around with Fusion 360 using its T-Spline surfacing functions but its not very robust (partly because of user error).

I am looking for advice on a budget minded software/workflow where I can take a preliminary solids model and reverse engineer a surface model so as to get smoother free-flowing shapes. One specific example of a need as follows. When I design castings that have complex cores they are the result of leftover space after getting all the structural design modeled as a solid. The internal cavity (sand core) is the leftover space. But its not good to have sharp edges like you get from prismatic solids modelers like Alibre and everything needs a draft angle about a parting line. Due to the complex shapes, solids modelers can not always compute draft and fillets, hence I am trying to solve the problem by re-designing the sand core with a surface modeler. A very important feature I must have is the ability to split molds/patterns that have a non-planar parting line, does not have to be automatic one button press solution but a software/workflow that does not take hours to do would be sufficient. Here is a screen shot of the initial design of sand core shape.



This is a screenshot of what I wold want to redesign it as.



I downloaded a demo of Rhino and the T-Splines plugin and am in the process of learning it. It seems a lot more robust than Fusion 360 as far as T-Splines are concerned when I draft less than ideal topology which I am working at improving. I would like to avoid spending the extra bucks on the T-Splines plug in if I can help it, I downloaded it to fix a surface I screwed up in Fusion. Anyways, my real question is do you think Rhino would be a good ticket for me and what other software should I consider?

Thanks,
Adam











I



would love to learn a work flow in Fusion 360 where I can take a preliminary solids model and reverse engineer a surface model so as to get smoother free-flowing shapes. The application of this is sand core box/patterns (molds) used for sand casting. When I design castings that have complex cores they are the result of leftover space after getting all the structural design modeled as a solid. The internal cavity (sand core) is the leftover space. But its not good to have sharp edges like you get from prismatic solids modeling and everything needs a draft angle about a parting line. Due to the complex shapes, solids modelers can not always compute draft and fillets, hence I am trying to solve the problem by re-designing the sand core with a surface modeler.I would love to learn a work flow in Fusion 360 where I can take a preliminary solids model and reverse engineer a surface model so as to get smoother free-flowing shapes. The application of this is sand core box/patterns (molds) used for sand casting. When I design castings that have complex cores they are the result of leftover space after getting all the structural design modeled as a solid. The internal cavity (sand core) is the leftover space. But its not good to have sharp edges like you get from prismatic solids modeling and everything needs a draft angle about a parting line. Due to the complex shapes, solids modelers can not always compute draft and fillets, hence I am trying to solve the problem by re-designing the sand core with a surface modeler.I would love to learn a work flow in Fusion 360 where I can take a preliminary solids model and reverse engineer a surface model so as to get smoother free-flowing shapes. The application of this is sand core box/patterns (molds) used for sand casting. When I design castings that have complex cores they are the result of leftover space after getting all the structural design modeled as a solid. The internal cavity (sand core) is the leftover space. But its not good to have sharp edges like you get from prismatic solids modeling and everything needs a draft angle about a parting line. Due to the complex shapes, solids modelers can not always compute draft and fillets, hence I am trying to solve the problem by re-designing the sand core with a surface modeler.