Symmetric revolve 359.75 degrees

[SYNDAKIT]

I'm pretty sure I could do a symmetric revolve up to 359.9 degrees in previous versions of Creo. 

Could someone let me know if that is true? 

I am using Creo 8 right now and it's maxing out at 359.5.

[StephenW]

I'm on Creo 4 M130 and I max at 359.5.

[SYNDAKIT]

The reason this came up is because I thought I could do it before but when I just tried today it wouldn't let me.

I decided to grab some older models to see and yeah I could do 359.9.

Furthermore, I can copy that feature into other parts and it works okay, I just can't create a new revolve feature and rotate it symmetrically 359.9 degrees...... weird.

Here is the part I'm talking about:

[Chris3]

Have you tried changing the accuracy?

[Chris3]

I can do 359.9

[SYNDAKIT]

Change it to symmetric and let me know.

[Chris3]

It works fine for me as a symmetric as well. I am using Creo 7 with a relative accuracy of .0012. My revolve was ~1" dia

[SYNDAKIT]

I think Creo 7 is where I had it working. 

Just to make sure, would you mind confirming that your revolve is symmetric and greater than 359.5 degrees?

[Chris3]

I went back and double checked and I am now seeing the behavior you described. I first created the revolve using the one direction default with 359.9. I then redefined the feature to be symmetric and I checked the preview and result to see that it still create the feature before I posted.

I now see that when I changed the feature to be symmetric Creo changed the value of the revolve to be 359.5 without notifying me which is very disconcerting.

[SYNDAKIT]

I was afraid of that. 
Thank you for taking the time to go back and check on that for me. 

-J

[Patriot_1776]

Yup, the accuracy is probably the factor limiting the OP.  OR, you could do 360deg, and then use a very narrow cut to finish it.  BUT, as thin as the cut is, you may very well run into the accuracy issue there too, so, I'd try tweaking the ABSOLUTE Accuracy first and save a feature.  OR, maybe do half of the revolve, then mirror the geometry.

[SYNDAKIT]

I tried messing with the accuracy but I didn't have any luck. 
Could you recommend an accuracy value to try out?

[Patriot_1776]

I'd start at .0001" and play from there.  That's my default setting.  You may actually have to try going smaller (.00005") or larger (.0005") to get it to work.  Larger values increase the "fudge factor", and sometimes that is what will allow something to regenerate.  Sometimes it needs more accuracy (lower number).  She's a fickle one, she is...

If none of that works, I'd try doing it in 2 halves as suggested.  This way Creo is trying to create something close to 180deg with over 180deg "missing", rather than something ALMOST 360deg with only a sliver missing.  Creo doesn't like slivers.

Best of luck!

[SYNDAKIT]

I know there are #ProWorkArounds but that's not what I'm trying to figure out here. It's specifically about if we can symmetrically revolve greater than 359.5 degrees. 

[MartinHanak]

INFO:

In Creo 3.0 M190 I can create 359.99 symmetric revolve using PTC solid_part_mmks.prt template (attached)

In Creo 8.0.0.0 I can create 359.5 symmetric revolve (only) using  the same template.

Please ask PTC Support to explain Creo behavior.

[SYNDAKIT]

Martin,

Your're the man!
thank you.

[StephenW]

It's an odd thing, like it is hard-coded in as a limitation. It's not like a regen failure due to accuracy issues.

But I do think Frank is right, Creo doesn't like itty bitty slivers.

[kdirth]

The only thing I can offer is a work around.  Sketch an arc and use a sweep.  I have been able to create a 359.998 degree surface with this method.

[MartinHanak]

https://www.ptc.com/en/support/article/CS277888

[Chris3]

Sounds like one of those cases (I have run into a few) where the programmers were like well this is too complex of a math problem to solve so we are just going to make an arbitrary limit that we know will work.

[SYNDAKIT]

Yeah that article was modified after I contacted PTC. It used to say that you could do 359.9 degrees. 
They are going with the "works to product specification" - of which they just updated from 359.9 to 359.5 degrees. 

[StephenW]

🤣 Well, that's the much easier fix for them!!!

I can see the point of the limit but seems to me it should be based on the geometry overlap failure instead of some seemingly random max limit.

[Patriot_1776]

Agreed.  It is not up to a code-monkey to determine OUR limitations.  There may be a perfectly legitimate reason we NEED to have a sliver like that.  I'm still annoyed that Creo STILL splits circles/cylinders into 2 pieces, that has caused me TONS of grief over the years.

[Patriot_1776]

I agree 100%.  Making things easier for the programmer should NOT be OUR limit.