Designer 2 change in behavior Draft and Feather

[DickB]

I've attached a portion of an mpc that I designed with Designer 1 for my Synchronicity clock project. A customer running designer 2 ran into a problem. The gist of the issue is that Designer 1 and 2 behave differently regarding Feather and Draft as illustrated by the pattern "face recess". Let me describe what is going on.

To make the face of the clock Synchronicity, I use the carve region "face recess" to carve .25" deep. As we all know, the carving bit has a taper. I desire a 90 degree cut for this region. So, I follow up with an offset vector cut "recess cleanup" with the 1/8" bit to get the desired 90 degree angle. (I have set the cut path to "No bit" in the mpc to better illustrate the issue.) As you may know, applying no draft or no feather plunges the bit faster than using feather or draft, and is harder on the machine. So I used small draft. I also applied 1/8" feather, (I'm not sure why - was it the default?) which in Designer 1 has no effect. This yielded the desired result. An offset cut using the 1/8" cutting bit cleaned up the small draft as desired. Again, the takeaway here is that in Designer 1, Feather has no effect, Draft does. Load the mpc in Designer 1 and play with both Feather and Draft settings to see for yourself.

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However, in Designer 2, the opposite is true.

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Feather is effective, but Draft is not. Again, load the mpc in Designer 2 and play with this for yourself. Unfortunately, Feather is "flipped" the wrong way, and cannot be flipped the other way (the Flipping button is in gray). If you compare the two screenshots that I captured, you can see that with Designer 2 the feathered carve region extends past the cleanup cut path. This ruins the final part. So Feather and Draft are not really interchangeable here.

I think this change in behavior between Designer 1 and 2 is not good. It messed up my project for my customer.

[bergerud]

Draft works from the top down. The pattern has to have an edge above the bottom. In 1.187, your pattern is like an upside down bottle cap with the edge at the top and so draft works. Feather works from the bottom up. The pattern edge has to be below the surface. In 2.0 your pattern edge is on the bottom and so feather works.

This behavior is backwards from what I would have expected since 1.187 automatically floors patterns. I was confused until I realized the patterns were inverted. The pattern in 1.187 converted the floor edge to a vertical edge. It looks like you turned a bug (I think of the floor thing as a bug) into a feature. It allowed you to use draft in 1.187. In 2.0 the problem is fixed and the unfloored pattern gets inverted without the ridge popping up. Now draft does not work and feather goes the wrong way.

The flip feather cannot save you because it only works with carve regions. If, however, you outline your pattern and use the outline, you can be saved by flip feather. Quality does not matter since you have the clean up pass.

I hope that all made some sense! (The top picture is 1.187 and the bottom is 2)

[DickB]

Draft works from the top down. The pattern has to have an edge above the bottom. In 1.187, your pattern is like an upside down bottle cap with the edge at the top and so draft works. Feather works from the bottom up. The pattern edge has to be below the surface. In 2.0 your pattern edge is on the bottom and so feather works.Dan, I'm not following this. It is the same pattern and the same mpc.


This behavior is backwards from what I would have expected since 1.187 automatically floors patterns. Are you saying that in 1.187 my inverted pattern has and edge on top because of automatic floor feather? One would expect to be able to duplicate results in Designer 2 by applying Floor Feather, but that is not the case. There must be some other difference in behavior that I can't put my finger on.

[bergerud]

I agree that the floor feather in 1.187 and in 2 are somehow different. I do not really know what the difference is. The effect is, however, reproducible in 2.0. See the attached screen capture. Original pattern on the left. Bottom right - saved with floor feather off and then inverted. Top right - saved with floor feather on and then inverted. (Bit optimization best was required to see the ridge. But draft works on the ridge with or without bit optimization.)

It is true the mpc is the same but the pattern (which is also the same) is inverted. The pattern is not saved inverted. The inversion must be a different process in the two versions of Designer.

[DickB]

The issue is that a project that worked in Designer 1 does not work without modification in Designer 2. I guess I will need to add a caveat emptor with my projects from now on.