We are using a V-carve bit to make stars in an American flag and trying to do it in a number of different sizes. Once we get to the larger sizes, we are having a weird issue…when the bit carves from the middle of the star out, the stars look great! But when it carves from the top of the point of the star, it puts a minor bend into the star, which makes it look bad.
Why is it doing this? Is there anyway to make the Shapeoko carve from the middle of the star every time?
Also worth noting that the board doesn’t move and not all stars do this…it’s just a handful and they aren’t in any particular grouping (not at the same time, in the same area, etc)
Please post the file you are having difficulty with.
Possibilities include:
feeds and speed rates and depth per pass setting — please check these
trying to cut a star which is larger than the diameter of the V endmill you are using — use a less acute V endmill with a larger diameter or model the star as a 3D shape
That smells like a mechanical issue - x-y.
Regarding “the other flags” - for some reason it seems like about 20% of the universe makes a flag as one of their first v-carves . Problems usually show up with all sorts of things trying to do so.
Obviously you need to look at your F&S, it may not be the entire problem but you cannot get a spindle speed of 7639 with a router on the Shapeoko, the minimum is 10K on the Makita, 12K on the Carbide and 16K on the Dewalt. This is probably the default in Carbide but it is only applicable to the Nomad, it is a well-known issue for Shapeoko. If the router speed is double, your feed rate would need to double too. I also agree that the depth per pass is probably twice what you should use for detail work like your stars. What is the speed setting on your router?
. Problems usually show up with all sorts of things trying to do so.