CNC router tools for hydrofoil board and wings

General Discussion
1

I kitefoil and ran into someone that is making efoil boards in town and he asked for some help with the toolpaths and possibly looking into cutting some wings out of foam.

I only have experience cutting metals on a cnc so all my speeds, feeds, and 3d machining stepovers are much different than a cnc router cutting foam. If someone could help me with what some industry standards are for a home cnc router type machine speeds and feeds are that would be appreciated. My biggest question would be on the tools that people cutting surfboards are using. Are they starting with a bull nose type end mill and changing to a ball nose or is the amount of time involved in manually changing tools and measuring offsets not worth it. Perhaps only use a ball nose?  My mind is programmed for really nice metal surface finished using 3d maching toolpaths so I have no idea the size of the scallops acceptable in this environment. In my ignorance I’m willing to leave sizable scallops on the boards, but if he is cutting a wing I’d like to really reduce the stepovers to get as close to the geometry of the wing as possible. I’ve also never cut foam so I’m sure there is a point where the accuracy benefit of smaller stepovers goes out the door due to the foam not cutting as accurate as metal cuts.

I’m also wondering what size cutters you all are using. I threw in a 1" ball nose on the below finishing toolpath on this race hydrofoil board with 10mm stepover which should leave a .04" or 1mm scallop height and got a 10 minute toolpath. Wondering if boards take this long for operations.

Thank you.

 

 

2

Here is the link to the toolpath I mentioned above at a 10mm stepover and 1mm scallop height

https://imgur.com/a/QX5vBv8

3

Cool!  Exactly what I needed.

4

This is a tough crowd for CNC shaping questions. You’d be better off asking a local board cutter or look up some information on the web pages of CNC surfboard cutting machine manufacturers. You will probably find they leave the native 1.25"  ballnose or large perpendicular wheel in the machine and accept a level of ‘scrubbing’ on the cut product. 10 mintues seem really fast for a ‘chunky monkey’ foil board but I am used to a smaller CNC machine and smaller cutters. You will need to experiment with your foam, machine, and cutters to see what works best. For a foil or fin from wood I would use a flat end cutter with a very small stepover.

 

 

5

Way over my head, but if you are located in North San Diego County, the industrial area across from the airport is home to quite a few CNC Machines.  You will most likely find though that a Pro- Cutter is not going to give up much in the way of “secrets”.  AKU and Shape 3D are primary and may get you going in a direction.  There are cutters who are already doing what you are talking about. But they’re not going to give up much.  Try contacting “Blue Shed” in Washington State.