Theres at least one forum I know thats dedicated to making scale helis.
There's lots of choices for heli mechanics around.. To some extent it depends on the heli you are modelling and if you are using a premade fuse.
For example all the scale heli fuses I offer are based around align 400,500,600 etc or a clone.. THough the have parts to also fit them to logo16, swift etc in many cases.
Have a look at
http://www.scalerchelis.com/phpBB2/portal.php