Part I of this build can be found here. At this step I started following the manual and proceeded to build the arm parts. Some metal shafts will be used to hinge the shoulder joints so at this step I used my trusty 6 inch metal ruler that has a millimeter scale.
The shoulder joints call for a 13mm length shaft with 1.5 mm diameter. I measure the length by placing the shaft horizontally on the ruler then raise it vertically to measure the diameter.
The shaft should fit right in with a little bit of tightness, I use a pair of pliers to insert the shaft in. The grooved part of the end of the shaft is what eats into the plastic to lock it. Here in lies the importance of being right the first time, as with that locking groove at the end, it will be hard to lock it into place again if ever you have to remove the shaft because of the mistake of having chosen the wrong one. The plastic is a bit soft so take care to not break the plastic with excessive force.
Here's both shoulder joints fully assembled
Next step is to insert the ball joint of the shoulder joint into the upper arm block. In that step there is a rubber polycap like block inserted first into the upper arm block. It works like those polycaps in Gundam model kits.
Here's a shot of that polycap like block inserted into the upper arm block
At this step, to put the arms together a small precision screw driver will be required.
To fasten the arms together, the flat head screw will be used, as indicated in the manual
Here's a shot of the shoulder joints assembled together already with the upper arm block.
Next is connecting the upper arm covers that were painted on. There is a proper orientation and positioning for this so it would be good to take note of this. The upper arms covers are supposed to be able to move by sliding once its connected on to the upper arm block.
One thing I should have done was to paint fully even the inside of the upper arm covers as the unpainted inside can be clearly seen during battroid mode. The parts are supposed to be glued together, but I didn't bother to glue them since they formed a tight fight. But don't take that as a recommendation from me...hehehe
Some gaps remained when I tried to join together the upper arm covers, in order to properly seal it I wrapped the two parts in thick swath of tissue paper then gently clamped them close by means of a pair of pliers. The tissue paper is to prevent the pliers from scratching off the paint.
Next is to put the other parts of the arm together.
This is held on together by means of a flat head screw.
For the elbow joint, 7mm length shaft with 2 mm diameter is required. Once again using my ruler to make sure I get the right shaft part in
Using my pliers to put the shaft in
The elbow actually pivots in two parts, the first was in the shaft part above, the next is at a polycap jointed place. To hold the two side covers of the polycap like joint in, it is recommended to glue the two halves together.
Here's the upper arm and elbow part already pieced together
Next is to put the forearm together. The forearm also serves as a storage area for the hands during fighter mode. I myself never built the hands as I was never a fan of the default hands since they never seemed to work well for me in their purpose of holding the gunpod
This is the base of the hand, this is the part that rotates so that the hand can be stored inside the forearm. This is also the part where you stick in the optional hands. The manual calls for the two halves to be held together with glue.
Here's the two halves glued together. Take note of the orientation of the part and be sure to test fit it first in the forearm to see if it swivels well and that the forearm cover closes properly.
Time to join the forearm together with the elbows. The joint at the end of the forearm goes inside the hole of the polycap like joint. The two halves of the forearm are kept together by means of a flat head screw.
Here's a shot of the arms all built. Forearm covers are also attached and checked if they open and close smoothly and fit in tightly
After using the screws and shaft parts, I made sure to properly seal the bags by means of tape so as to make sure I don't lose any of them. Yamato gives you only the exact number of shafts and screws so you could just imagine the amount of hell breaking loose if you lose one of them!
Part III of this build can be found here.
