Mp5 v2 gearbox motor height

[Sewdhull]

I need tips for setting motor height in the v2 box. 

The mp5 grip extends way up so I can't see the bevel gear to even start the process.

Any tips, do I need to make a jig? Guess?

[Pseudotectonic]

you can figure out the ball park height of the bevel gear by just inserting the motor without the grip, and as long as the motor tower is centralised and perpendicular to the hole and has just about right wiggle room when it is engaged with bevel at the depth you want, then it should be in the right ball park, and then afterwards use sound to do the final adjustments

 

or use another spare m4 grip to shim it, and then use sound with the final grip

[Sewdhull]

It's the centralising bit, I'll probs need to use a jig, just some tube to align the motor.

[Pseudotectonic]

Or wrap some tape around the motor tower? (Or brass tube it) which you will want to do anyway?

 

The alignment does not really matter at this stage because the grip will align it afterwards, you just need to worry about the height for the shimming (as in how deep the motor is going into the gearbox when it is more or less centered in the hole)

 

Once you are centered in the hole, the bottom of the motor will sit at the bottom of the grip, and these two points should automatically align the motor correctly

[Sewdhull]

The height of the bevel gear is what I want to sort first, too low and the motor pinion will be too far up the gear, too high and the pinion will be too far down.

In a v3 you can see this relationship in this v2 ya can't.

[Pseudotectonic]

yeah when you centralise the motor tower and insert the motor to the right depth ("motor height") you will have the reference for how high the bevel gear should be shimmed at

 

i suppose this is a simplified half-shell method, you don't install the motor grip but just shim the motor tower until it sits more or less centralised to the gearbox shell motor hole (or half of it)