Problems With Face Draft

[DaleLloyd7569]

Hi,

I am having a problem with the face draft function and and am not sure why it is happening.
In the attached file I want to add face draft to the ends of the two half hexagons, but when I try Inventor says it does not produce any meaningful results and fails.

Before I extruded the two half hexagons I had put face draft on the two semicircles but removed it before doing the sketches for the half hexagons. But now even if I delete the two extrusions Inventor won't allow me to redo the face draft on the semicircles

Thanks

[JD Mather]

Why did you duplicate the origin planes rather than use them?
Why do you use zero length dimensions rather than coincident constraints?

In general wayyyyy too many dimensions that could be replaced with geometry constraints (primarily coincident to midpoint or symmetry constraints).

For your problem - Extrude with taper angle (but very unusual to dimension width of flat rather than flat to flat - what standard size wrench will be used).
Then use the Replace Face command and replace that one face where no draft is intended using the workplane (which should have been one of the base planes following the BORN Technique). http://home.pct.edu/~jmather/skillsusa%20university.pdf

[DaleLloyd7569]

Thanks JD.

I suppose I use dimensions rather than coincident restraints because having basically taught myself to use Inventor, if something I have done works for me then I have carried on that way, the same with work planes I usually put in a new work plane whereever I want a new sketch.

The hexagon shape is not to take a wrench it is actually a core print as I have found the most sucessful way to anchor a core in a bend pattern is to use a hexagonal shape, which resists core rotaion very well.

I know that the replace face method will work for me but I still don't understand why the face draft command won't work. I never had this problem when I was using Inventor 10, it has only happened in Inventor 11.

I will work try my next model with the BORN Technique and try using more constraints to simplify my models.

[JD Mather]

I would be intested in a significantly simplified model that demonstrates the problem (two features? one feature), to use to troubleshoot the exact cause - but not so interested that I am motivated to generate it myself...

[Zoner]

I seem to have the same problem.

When building a part using a sketch and extrusion and applying a face draft on one end, everything works fine. But if I want to add another face draft on the other end (of a U channel I built) I have to edit it in Inventor Fusion and lose all advantages of the parametric definition ... why ?

In fact why do I need to go into fusion to add the second face draft on an extrusion ?

I am new to Inventor, never used Autocad either ... but like the parametric construction of the parts ... until I wanted to add the second face draft.

[JD Mather]

I seem to have the same problem.

Obviously it is impossible to answer this question without the file.

[Zoner]

This Left U Channel, is a file done after 2 hours of free time ... first trial at Inventor ...

I am discovering parametric too, my center U Channel is quite fun, my left U Channel is less intelligent (i think lol)

I also included the Center U Channel to show evolution of understanding.

The 2 face draft is still a problem for me ...

Everything will be redone anyway since I start to get it with constraints ! Pretty cool.

[JD Mather]

Sketch1 indicates you need 1 dimension (or in this case - a vertical constraint on the line shown red here).
Also, you could simplify and remove one dimension by making those two lines equal = constraint rather than dimension both.
You should not be using Alias Edit on this part.

[JD Mather]

Depends on what face you select to take the draft from.

Also, you could do an Extrude-Cut or a Split or a Sculpt to get the same cut.

[Zoner]

Thanks for your fast reply

I understand that the sketch for the Left U Channel is not perfect, but the problem is applying the second face draft ... on the extrusion obtained from it.

I got the sketch ok (yes it could be defined more logically), I got the extrusion ok, I also got one of the face draft on the extrusion working but ... when I try to add the second face draft at the other end, it cuts the long part, not the end of the part ... removing the first face draft at the same time ... that is why I used the Alias Edit on the part ... That is my problem

I have to admit that I don't see how applying better constraints to the sketch could allow the second face draft to be applied ...