Implicit Hydrogens at 90°, fixed bond length

I would like to know if there is an option of aligning ALL implicit hydrogens on a hydrocarbon at 90° (seems to be impossible with the rotating function). And is there any way of setting the bond length to a fixed value? I can just simply drag the hydrogens in the position I want them to be in, but then the bondy length doesn't stay fixed like in ISIS Draw, which is then incredibly tedious. 

 

Thanks very much for any hints/pointers. The help function has been of no use so far.

Hi,

Holding the SHIFT key switches off the "15 degree" feature during the rotation.

The default bond length cannot be changed currently, but we plan to implement this feature in the future (together with chemical object resize). 

Best regards,

Akos