Sweep 2 Bulge vs Sweep 1

Hi -

I’m a newb finding a small inconsistency in the difference between Sweep 1 and Sweep 2. I’d like to have round tops and flat bottoms on this part for machining, but when I do Sweep 2 and get the flat bottom, the sides bulge out. I’m happy with the tops and sides of the Sweep 1 version.

Any help or suggestions would be appreciated.


Sweep1:Sweep2 Bulge.3dm (161.9 KB)

Software information

Software versions
Rhinoceros version: 5.0.2 (5A865)
IronPython version: 5.1.2015.131
Language: en (MacOS default)
OS X version: Version 10.10.5 (Build 14F27)


Third party kernel extensions
com.m-audio.driver.firewire (1.10.5)

Hardware information

Computer hardware
Hardware model: iMac12,2
Processor: Intel Core i7-2600 CPU @ 3.40GHz
Memory: 8 GB
Architecture: Intel 64 bit

Video hardware
Graphics: AMD Radeon HD 6970M 2048 MB
Memory: 2048 MB
Screen size: 2560 x 1440
Displays: iMac (109dpi 1x)

USB devices
Apple Inc.: FaceTime HD Camera (Built-in)
Apple Inc.: Apple Keyboard
Cypress Semiconductor: USB to Serial
Apple Inc.: Bluetooth USB Host Controller
Canon: MX470 series
Mitsumi Electric: Apple Optical USB Mouse
Apple Computer, Inc.: IR Receiver
Apple: Internal Memory Card Reader

Bluetooth devices
Apple: Apple Magic Mouse

OpenGL information

OpenGL software
OpenGL version: 2.1 ATI-1.32.25
Render version: 2.1
Shading language: 1.20
Maximum texture size: 16384 x 16384
Z-buffer depth: 24 bits
Maximum viewport size: 16384 x 16384

Implementation settings
Use texture compression: No

Appearance settings
Antialiasing: 4x
Mip map filtering: None
Anisotropic filtering: None

Model Name: iMac
Model Identifier: iMac12,2
Processor Name: Intel Core i7
Processor Speed: 3.4 GHz
Number of Processors: 1
Total Number of Cores: 4
L2 Cache (per Core): 256 KB
L3 Cache: 8 MB
Memory: 8 GB
Boot ROM Version: IM121.0047.B21
SMC Version (system): 1.72f2

If you tick maintain height with sweep 2 that will get rid of side bulges. However with a shape of this complexity you might be better off doing it in more than one command operation. Sweep one the top, loft the planar bottom then loft the sides. The top one in the image was made with three commands.

1 Like

Excellent. Many thanks! A better response that I had hoped for.

I probably should have done more trial and error with the options, but the term “height” didn’t seem particularly relevant or appropriate. Now, if it had said “Preserve weight…”