Some users have been disgusted with the 3d rendering time on a knurl. I have found the best way to keep rendering times down is, after selecting helical cut, enter only the height needed to pass the sketch through the part and no more. If the part is only .5 inch wide and you leave the extrude height at 9 inches the computer will figure for the entire 9 inches. This should save lots of time on shorter knurls. Long knurls will still take a long time. The feature pattern in the included part file was rendered in 1 minute on a cheap home computer. Download it and see how long it takes to regenerate the pattern.
Modeling A Knurl
- Thread starter TJI
- Start date
OTE_TheMissile
Alibre Super User
:shock: Wow, my hat's off to you, ya figured it out. I've tried to model a knurl a bunch of times before and could never pull it off; the complexity either locked up the computer or the features failed. I'm gonna hafta fiddle with this example you posted & see exactly how you did it.
Yes, seems a good technique :wink: :
viewtopic.php?f=9&t=4075&p=22345
viewtopic.php?f=9&t=4075&p=22345
OTE_TheMissile
Alibre Super User
I never thought about using a feature pattern though, I just did a helical sweep cut of a bunch of triangles all in a line next to each other. Made a copy of the sketch in the same place, did the same sweep cut but in the other direction, and voila...or, not. I think the intersection of so many angular edges at once is what did me in, by using a feature pattern I imagine Alibre models each pair of cuts in the pattern one at a time and can deal with the intersections as they occur. But as I've said before I'm no programmer, it's just my hunch.
The regeneration time of TJI's model is reasonable. Strangely though it loaded almost instantly, but when I rolled the "dogbone" back to check out the features then rolled the model forward again, that's when it took about 30 seconds to finish working.
The regeneration time of TJI's model is reasonable. Strangely though it loaded almost instantly, but when I rolled the "dogbone" back to check out the features then rolled the model forward again, that's when it took about 30 seconds to finish working.
MilesH, after clicking on your link I see that I have " re-invented the wheel " so to speak. 
However, there might be some value in this post as it stresses the importance of keeping the helical extrude height as short as possible. By the way, your pattern regenerates faster than mine does! :mrgreen:
However, there might be some value in this post as it stresses the importance of keeping the helical extrude height as short as possible. By the way, your pattern regenerates faster than mine does! :mrgreen:TJI said:MilesH, after clicking on your link I see that I have " re-invented the wheel " so to speak.
The more times these techniques are posted, the more people take them onboard
Yes, minimising the height of Helical features is a good point.
Not sure why my pattern regenerates faster... :mrgreen:
OTE_TheMissile
Alibre Super User
OK so I'm trying to apply this technique to the ø.875 foot pedal on the '09 Harley Davidson centerstand we're working on, but when I adjust the sweep's pitch to where the diamonds run parallel to the centerline, the triangle turns into a narrow slit. Not quite sure which dimensions affect what in making this feature, probably doesn't help either that I'm not knurling this rod all the way to the end.
I wonder...could Alibre model the helical sweep if the triangle sketch was drawn on a plane 90° to where it is now? i.e., if in Sketch view the axis you'd be using as the centerline went into the screen of the monitor and out the back, rather than side to side or top to bottom?
I wonder...could Alibre model the helical sweep if the triangle sketch was drawn on a plane 90° to where it is now? i.e., if in Sketch view the axis you'd be using as the centerline went into the screen of the monitor and out the back, rather than side to side or top to bottom?
OTE_TheMissile, make sure in the helical extrude dialogue you click the advanced tab and select "normal" for profile orientation. Even though it won't show on the screen it will force your sketch to turn and face the helix angle you input. If you select orientation as parallel the sketch will remain as you see it on the screen and will be dragged sideways through the part and cut the slit you were talking about. As to drawing the sketch 90 deg. to the axis of rotation, so the axis line comes out of your screen as you said, it would make some helical work much easier if we could pick either an axis ( like the rotate tool ) or a reference line. This would be a good program improvement. I hope I understood you right, I got and error when trying to open your part file.
Found it: viewtopic.php?f=6&t=1880
