I am trying to create a flute with spherical ends. I used the 2 point arc to make a 5/8 diameter half circle and closed the bottom. I then made a 1/4 circle with 5/16 radius at 90 degrees to the first arc. When I used follow me to rotate the 1/2 circle as a cutter it kicked the bottom edge off the axis line lifting off of my surface. I’m sure screen captures would explain it better but I dont see where i can attach them.
Drag them to the reply window.
And also do that with your model.
Follow me will always start and finish perpendicular to the first and last segments of a curve.
By the sounds of it you have non right angles at both ends of your path. If you correct that your shape will work.
Carrying on from what Box wrote, set up your profile and path like this so that the start and end of the Follow Me path is perpendicular to the profile.
Due to the tiny size I would suggest creating a component of that profile and path before running Follow Me. Then make a copy of the component and scale it up by a factor of 100 or 1000. Open the large one for editing, select the path and run Follow Me. After it’s complete and you’ve done any required cleanup so it is identified as a solid, exit edit mode and delete the giant copy. Return to the original and it should be in could shape to use as a cutter.
Did you follow the directions I gave you and scale up the component before running Follow Me?
As for your last two screenshots, read what Box wrote about the path starting perpendicular to the profile. When you set up for Follow Me as you have, the profile gets projected, not rotated, to perpendicular to the first segment and the extrusion ends perpendicular to the last segment just as your last screenshot shows.
The missing faces in the extrusions is due to the “tiny face” issue. That’s why I suggested the workflow I did.
If you must create the flute cutter starting with the end half circle profile, create the path so its first segment is perpendicular to the profile. One way to do that is to start with a circle and rotate it so an edge segment is parallel to the axes instead of having a vertex on the axis.
Divide the edge of the circle at the midpoints of the segments and erase what you don’t need.
Make the component and scale a copy up before running Follow Me.
Another way to do it would be to add edge segments off the ends of the arcs at each end. This will require some additional cleanup work but it can be used for creating the cutter.
One thing you might find helpful for modeling cutters is to think of the volume of space a router bit or shaper cutter would pass through in the real wood. In many cases it’s easier to model the cutter longer than the cut. For example, I modeled cutter volumes for the stopped chamfers on the undercarriage of this hay ray table. The cutter shapes extended well off the component they were cutting. Think turning on the router before you make contact with the wood and pulling the router way from the work before turning it off.
Another example here. I drew cutters for the radius top and bottom of the side frames for this shelf unit. The cutters started a little before the back component and ended a little beyond the front end. I used Trim to cut the roundovers on one component and Subtract for the second.
That won’t help the OP.
You’re right. I wasn’t suggesting it as a solution for the OP’s current workflow. I just thought it was interesting that I had recently implemented the same geometry parametrically.
You cannot run plugins on the iPad version.
If it helps, I can also share a simple .skp file of the geometry.
Well I may be giving away part of my 3D Basecamp talk for November, but anyone can make themselves a number of primitives as starting shapes and save them out as components to be brought in later. On the iPad, there isn’t a component palette to do that with like desktop, but you can drag one in from the Outliner by clicking on the three … and choosing “Insert.”
Yes, that comes from doing a partial circle without a first and last segment to establish the right perpendicular condition. (I remember in college there being at least a text book if not whole course on “Initial Conditions and Boundary Value Problems,” meaning - what happens at the boundaries is crucial.). @DaveR describes methods to make partial circles that start and end straight, but I used a different approach: I made a full sphere, and then just deleted the half I didn’t want.
Switching to orthographic view temporarily helps with making a precise selection:
From there I made a cylinder extrusion of one radius so that the whole component has a cube as a bounding box for scaling purposes (I had to use the Dave method for small faces as well). I positioned the cutter end component at one end and used mirror to establish the other end, edited the component and extended the cylinder ends till they met in the middle, then exploded and combined them into one whole cutter.
Sorry I didn’t document every step as I fumbled along myself, but it was an interesting exercise to force myself to do the whole thing from scratch just on iPad.
The finished file:
Rond bit flute WS v1,0.skp (215.0 KB)
Another method that will work with Ipad, assuming you understand tiny faces.
Simply in the interest of avoiding what I should be doing.
