Before Assembly

 Please to read "How to work with 3D printed parts" and to clean and trim parts.

Gun Recoil

Smooth inner surface of A7 for barrel movement.

Smooth surface of gun barrel extension too

Push metal gun barrel to extension with force, no glue is need.

Bolt gear rock to barrel extension with MA1

Insert barrel assemble to cradle

Bolt servo with MA1 screw

Connect servo to TK22 to set servo to normal position then bolt servo gear with the black screw in servo accessory bag

Note the angle of servo gear

Bolt elevation gear with MA3 screw

Insert mantlet

Bolt mantlet with MA9 screw

Completed recoil assembly

Remove some internal structure in upper turret

Insert recoil assembly

Insert MA6 screw to Tunnion L and R

Fit tunnion on both side,  note the direction of tunnion

Bolt tunnion

Now the gun can elevate and depress correctly

(Optional)Fit TBU base to elevation servo stand with MA3*4

Fit to upper turret

Bolt it with MA6*4

Fit elevation servo fixture with MA1

Bolt servo gear with the black screw in servo accessory bag

Insert MA4 screw to the slot on servo fixture

Fit elevation gear assembly to the stand

Connect servo to TK22 to set servo to normal position then tight the screw to fix

Put lower cover back and bolt it

Open the hatch, can see the TBU base, done!