29 November 2012

Melonchopper Build Pt. 1: Initial assembly

The Parts Came In!

It's like Chrsitmas!

So I ordered almost all the frame materials for Melonchopper off McMaster. Two days and $320.00 later, these arrived at my place. 

Inside were all the goodies: 8020 1010 extrusions, .25" and .125" plates for waterjettng the framing materials, aluminum tube for steering column, threaded rods and ball joints for the steering, 30 four-packs of 8020 T-nuts, steering FR-10 bearings, shaft collars, and some additional tidbits. Time to start building!

First, I roughly cut the 6" rear frame cap and steering column support, both made out of 8020. I used a horizontal bandsaw for the first time, only to find out it's terribly inaccurate. 

To clean up the crappy job the horizontal bandsaw did, I faced the rough end of the extrusion on a mill. 

Already looking good! I temporarily used the steering column support 8020 as a spacer for the front bumper (They're both 6") and placed the seat roughly where it was in the CAD model to determine if my feet would reach the bumper comfortably. 

They didn't. 
As didn't other tiny aspects of Melonchopper's geometry when it came to seating a person. I'll just modify them as needed, but one thing I'm sticking with til death do we part is the steering. I spent hours tweaking the geometry to make its behavior as ideal as possible. 

Speaking of steering, let's cut the shaft down with the bandsaw, shall we?

I also cut the steering rods to the appropriate length with a hacksaw, and cleaned the edges with an abrasive grinding wheel. 

And here's one of the nifty 1/4"-28 ball joints. They have two rotational degrees of freedom and allow 70 degrees of play in each direction. 

I've done all I can do today. Off to sleep until I can waterjet things...

No comments:

Post a Comment