Utility Arm Hybrid Part 1

Frank Pirz' Utility Arm box + Automated Mechanical Utility Arm kit

The utility arm box was ordered from Frank on one of my last orders, he sends a flat pack for creating of a utility arm box. 

• This kit allows through use of spacers and pins to install free swinging utility arms to the frame. 
• The kit comes with spacers to align the height of the arm box to the skin (because there are various skin alignment issues.

Here is a photo of the utility arm box that Frank designed for us.

 

Here is a photo of the automated mechanical utility arm configuration

 

I started pulling the pieces out and seeing how they fit together, dry fitting.

 

Installed the motor on 1 of the arm mechanical pieces so I can see clearance if I try to fit it into Frank's utility arm box.

 

Started gluing the sides together which connects the box

 

The upper and lower parts of the box looks similar, once side has a large hole where you install a bearing piece into and the other is a small hole. 

 

Using weld-on #3 began gluing the pieces.

 

Ran one of the shafts through the 3D printed utility arms.

 

Dry fitting the arm box to see clearance issues with the mechanical arm metal pieces in the center.

 

Traced and cut clearance to fit the mechanical utility arm center piece snug.

 

this is how the center mechanical center piece will fit 1 on each side of the plastic center piece.

 

I layed them onto the center plastic piece and taped them tightly together using the existing holes between both and the center plastic piece.  Once taped and aligned, I was able to drill through box to install screws to hold them together.

 

 

I then traced the sections where we needed to cut out to allow for the hitec motors to be installed on each side.

 

I pulled out my tiny handy dandy styrene table saw made specifically for cutting plastic.

 

 

Here is a great view of the blade exposed.

 

I slowly ran the pieces through the saw cutting each out.

 

Here is the other side cutting the piece out.

 

Once complete, I verified alignment of the metal pieces to the center plastic piece.

 

I then set some screws (8/32" through the holes to see how it will align correctly.  Also verified that the metal center pieces fit correctly inside the box.

 

 

Here is a top down view of the utility arm box showing the two metal mechanical arm pieces hanging out the back.

 

Removing the metal arm holders, made sure that the box was glued and allowed to dry and harden.

After drying you can clearly see the nice aligned pieces, Weld-On #3 dries very fast and merges the surfaces together well.

 

Here is a view with the mechanical arm piece installed.

 

With the mechanical Arm piece in, everything aligns up nicely.

I counter sunk the holes in the upper mechanical arm metal piece allowing the 3/4" 8/32" screws to sit flush into the metal.

 

Installed 3 8/32" X 3/4" screws and fasted on the other side with nuts.

 

here is a view showing the bottom of the 3 pieces connected.

 

better view

 

Here is the utility arms manually connected and the inner skin attached to the frame to see alignment issues.

 

The alignment looks very good, infact the 3 pieces allow the center arms to sit perfectly to their holder cutouts.

 

Here is the test fitting of the mechanical arms to the hybrid utility arm box.  I will have to attach the gears and belts as well as the hitec armature motors to turn them.

 

yet another view.

Here is a closeup of the right arm and the gear and axle that will allow the arm to rotate and swing in/out.