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Standard crank

When a standard crank is created can you please leave the length to be chosen and not frozen?

Standard cranks

In version 9.15, there were four cranks included in the standard cranks library which did not have any length designation in their names.  Of course, each of these cranks were of some specific length.  As you noticed, that length could not be changed for that specific crank model.  Under those circumstances, I think your suggestion to leave the crank length editable is a good one.

However, the alternative would be to ensure that cranks in the library are stored with a specific length in their name.  This was the precedent I tried to set when standard cranks were first introduced, and I think I'd like to stick with that.

In version 9.16, the four standard cranks that were added in 9.15 turned into 8 standard cranks in 9.16.  Each crank has been renamed with the length in millimeters being the first part of the name.  You will now find a 170mm and a 175mm version of each crank.  If you'd like to create another variation on any of these cranks, for example a 172.5mm version, you can do that as follows:

  • Pull up the 170mm version of whatever crank you like.
  • Switch to the Custom menu.  Doing this will retain all the same values contained in the standard crank, but the fields will now be editable.
  • Change the 170 length value to 172.5
  • Click the Add to library button
  • Give the new crank a name.  Ideally, use the same naming convention employed by the original crank.

Please use caution when using any standard component.  I cannot guarantee that all dimensions perfectly reflect the dimensions of the real component being modeled.

Also, when looking at standard cranks, be aware that the Q factor dimension is included among stored dimensions.  However, Q factor is not always strictly a function of the crankset.  Q factor can also depend on the length of bottom bracket spindle.

All owners of BikeCAD Pro will find the latest version of BikeCAD available for download in their Files tab as described at: bikecad.ca/downloading_bikecadpro.

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