When I lent my services to a collegue who was working on a film about 12 years ago, I was introduced to the world of cnc. I remember watching this huge machining centre milling out a slab of mdf and turning it into a fantastic set of gears. I knew that it would have taken me hours to achieve the same thing with traditional power tools. I decided then that I would invest in a cnc router for my own business Oxenham Design. At that time I could turn on a computer, but even to check email seemed like a crazy set of operations. I persevered and learned every piece of relevant software I could get my hands on. I am now fortunate enough to be using Vectric's ASPIRE software, and Techno cnc routers, which has helped us to create some amazing projects, both in part, or in full. I thought that this blog would be a great place to share "behind the scenes" adventures with the software, materials and equipment we use, as well as the projects we build.

Thursday, 27 June 2013

Nice Knapsack Little Man!

We got all of the styrofoam cracked off the bases. It was certainly laborious! The final step was done with the pressure washer I borrowed from the amazing neighbor! This blasted off any remaining deposits fairly quickly.
 There was some air bubbles, but that was solved with some quick bodyfiller magic!
But the rest of it looks exactly like I was expecting to, Woo-Hoo!
After the edges were all trimmed off, the next course of action was to cut the slot that the little man will ride in. The underside of the base gets 3/8" mdf glued and screwed to it, so I used it as a cutting guide. The mdf won't get glued in until the end assembly, in hopes to keep all the mechanics aligned and flat.
Our Techno cnc was able to quickly churn out the 1/2" pvc base plates. These plates get mounted with spacers to the underside of the aforementioned mdf plate. This will be the base that all the lights, sprockets, motor and chain will mount to. That way it will all go inside the game at once.
The sprockets have a fairly large shoulder on them. So I pocketed out the base to have the sprocket sit in the material. This gets the chain as low as possible to the base. The sprocket will spin on the t-nut, with a 1/4 20 bolt threaded in as the post.
2 nuts for locking, and some additional thread locker should keeps this together. Even if the nuts were to spin off, the sprockets and posts are still trapped in the base assembly.
The pvc strips helps solve 2 problems for us. The chain runs through the track, with very little  clearance. This way the hiker man will travel in a perfectly straight line to each checkpoint, eliminating any binding due to a loose chain. They also become strengthening ribs for the base. I like killing 2 birds with one stone!
While I was designing the 3-d portion of the bases, I had to have a fairly accurate size for the hiker. So I went with 2 little plastic figures I got at Wal-mart. We're modifying him a bit, but not much.
Jody re-sculpted his legs in a running position using Avery's Apoxie Sculpt, a 2 part epoxy sculpting epoxy.

And she added a little back-pack. Probably for his little sandwiches and stuff! He'll obviously get a repaint, but he looks really good right now.

It feels like not alot is happening, but when I re-cap everything at the end of the day, we're doing just fine.


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