Can't create a simple dome in mm's
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Hello Sketchupers,
for the last week or two I have been struggling to create a bathtub shape. My intention was to create a flat rounded oblong add an thin arc profile at 90 degrees and use the follow-me tool to run it around the outer path of the oblong.
Hours later I am no further as the outcome is so unpredictable it never seems to be the same twice.I have gone back to basics and have just gone through Gaieus' excellent "Dome" tutorial to see if I had missed something. I cannot even produce a closed dome, the centre segments always seem to be missing. However after downloading some of the examples from the tutorial they seemed to work fine and produced "closed" domes. When I started from scratch and did exactly as in the tutorial... no joy. The only difference was that I was using a "mm" template and the tutorial was done in inches. When I switched to inches.. IT WORKED!!
I have attached 2 files which are identical (I think) except that one is done in mm (circle/arc dia. 12mm and 15mm) and the other is in inches (12" and 15" diam). The only obvious difference is that the "inch" dome is complete and the "mm" one has a hole at the top. Can someone check these and provide an explanation why the dome is not closed?Thanks in advance
Tim
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Hi Tim,
You realize that 12" are about 25 times bigger than 12 mm?
The reason for your failure is that SU cannot handle (more exactly create) very small faces - ones that have around (or smaller than) 1 mm (1/16"). This is a limitation of the OpenGL engine and there is nothing we can do - except to model at a larger scale.
Now as it seems that you are working in metric, simply use a template with (or change your units to) centimetres (that would be enough I guess) and continue "pretending" to count in millimetres. Of course, you will end up with a model 10 times bigger than what you need but at the end, you can easily rescale it to 0.1 and the small faces will remain there.
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Hi Gaieus,
I have just been experimenting and had also come to the conclusion that it may be better to work in some other (larger) unit. I only want to produce an illustration where the scale is not really an issue so I'll carry on down the route you suggested. But don't worry I'll be back with other questions I am sure
regards
Tim
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