INTRO

The assembly of the space frame around the upper crank mechanism was shown in the previous page (2). This page shows the attachment of the middle braces and the lower crank assembly.

This is located approximately where the arrow is indicating below.

Location of middle braces (approximately)

Once completed it will look like this:

Middle braces attached*

(* Nb., please ignore the ‘Y-frame LHS’ component to the right of the image for now [yellow arrows above] – this is to be added on the next page).

PARTS

List of components presented in this post:

  • Middle brace 1 (#12) “MB1”
  • Middle brace 2 (#13) “MB2”
  • Middle brace 3 (#14) “MB3”
  • M3 csnk socket screws, 10mm (x4)
  • M3 socket screws, 16mm (x2)
  • M3 nuts (6)
  • M3 washers (4)
Exploded view of the new components

The image below shows the new 3D printed parts labelled…

New components in wireframe view & labelled

These parts are shown below:

Middle brace 1 design

This is shown 3D printed (black PLA) below.

Middle brace 1, 3D printed and with captive M3 nuts inserted

Middle brace 2 is shown below

Middle brace 2 design
Middle brace 2
Middle brace 3 design

This is shown 3D printed below with captive nuts inserted.

Middle brace 3 with captive M3 nuts

It is now necessary to join MB1 & MB2 using countersunk M3 screws x 10mm, plus nuts and washers as shown:

MB1 & MB2 joined

Nb in the above image hex-head machine screws are shown this was later changed* and countersunk M3 socket screws were used (10mm long) to provide more space for the parts above it. This is shown below.

(* Website photos to be updated).

Middle brace 1 & 2 joined with M3 csnk socket screws

The Middle Brace 3 part can now be attached but do not yet fully secure the screws and nuts to MB 2 (orange arrows below) as it needs to be attached to other parts first.

MB3 attached to MB2 but screws should be left finger-tight for now

Middle brace 1 attaches to the left and right L-shaped braces using M3 csnk screws, 10mm long (yellow arrows below).

Note that in the image below hex-head screws are used to secure MB1 to MB2 but these have been changed (orange arrows below; website to be updated).

Middle brace 3 attached but not yet secured

(Nb ignore the attachment of the left Y-frame (to right in picture above; purple arrows) which is explained on the next page).

Next is to attach the two Y-frames (left, right) and the central torso brace. This will be done on page 4