Garage Door Chain Drive Gear

This is a modified version of Mudfoot's chain drive gear. One design flaw in faithfully recreating the nylon gear that comes in a garage door opener is that it has stress points that printed parts cannot handle. By making the roll pin slots beefier, the gear will not shear apart after the first use. It works on MANY garage door openers, and if printed in a tough material (I use PETG) it can last quite a while.