Chopper Design Documents
& Design Changes/Issues.
This page is a list of the design documents that I've found and used in creating the CNC version of Chopper presented here. There are a small number of design issues that I'm also posting here. First, to make others who may not have stumbled across them aware of potential problems. Second in an attempt to get a concensus if what an acceptable solution might be. Third to draw attention to design changes I've made to make building Chopper easier.
This page is a work in progress and is very incomplete as of 04/09/19.
|Cleofett's AutoCad Drawings|
source for Chopper's design has been an AutoCAD drawing file created by
Cleofett. A portion is shown to the left.
See his Astromech forum blog entry here.
You can download the drawing from: dropbox.com
AutoCAD, by AUTODESK, is a relatively easy to use 3D drawing format. It is easy to apply dimensions to Design components. That's necessary when you are converting to a different CAD format.
Dassult Systems offers a free download of it's Draftsight software an AutoCAD "work-alike" [it's a free trial which continues to work after you decline to purchase it. Some of Dassult's extensions to basic AutoCAD are disabled but you don't need them.]
You can download it from the Dassult website.
|Joymonkey's Skin Drawings|
|Battery Box Crash|
Battery Box was derived
from Cleofett's .dwg drawing files. However, as noted
TinyP the original 6.625 in tall battery box hits the body in 3-leg
See TinyP's build log, page 8, scroll down to post #74
to quote him: "One compromise that I already anticipated was the battery box hitting the body when in 3-leg mode so I had to adjust the height of the box closer to 6" instead of 6.5".
Picture Left & text above from TinyP's Build log
|Outer Edge of Leg Crash|
|After I posted my
preliminary CNC design for the legs, Matthew Zwarts warned me that
a problem with the Leg design crashing into the foot shell. The pictures below illustrate the
problem and the fix that I'm proposing.
The image below links to a .dwg file if you need more detail. The left drawing is the Cleofett original. My first thought was to simply shorten the offending section keeping the angle the same (shown in the center drawing). That however would leave the detail part hanging over the edge. My second choice, illustrated in the 3d model above, and in the right hand drawing, is to change the angle of the leg part so the outside edge matches the inside edge.
|This is a 3d model of the revised leg profile shown at the same angle as the image above.|
|Space inside the Foot Shell|
Chopper Home Page