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.

Friday 28 June 2013

Go Climb the Mountain Little Guy, I'm growing Tired of You!

While I was busy laying out the cut files for the miniature party cabin that resides at the finish line of our little game, Jody got the 2 hikers all painted up. I think she's going to do a bit more, but they're pretty much done.

I exploded the sides off the little model cabin in Hexagon. I actually used a combination of the original building, and the building that was trimmed by the surrounding geometry of the rocks on the base.

After I had the sides exploded, I exported them out as a dxf file for import into corel. I hate dxf files, I think they're antiquated and frustrating. Plus, all the curves get broken into facets.
Once the file was in corel, I quickly cleaned it up, and added the little windows. Lamina design was essential for flattening out the curved roof that rests against the jagged mountain rocks. This "should" be as close as possible to fitting against the rocks. I'll test it tomorrow!
 Once the building was scribed for wood siding, corners mitered, and glued up, I was able to test fit it. Perfect! I had to remove a tiny bit of the mountain to allow the left side of the door to fit, but I was expecting it.

 The next step was to get all the window trim , and roof pieces cut from .060" styrene. The roof will get strip shingles, so it will look thick and very coarse. I want the shingles slightly out of scale for the house, which should look great.
I was also putting off solving the drive motor assembly, but had to deal with it today! We're using power window motors for this job. These always seem be what I turn to. They're pretty cheap, have gobs of torque, and only really need about 5 amps at 12 volts, under heavy load. I was going to make a rigid pvc collar that would fit the splines on the shaft, but by milling down the mounts on the gear-box, I could use the sprocket right on the metal gear shaft.
I had to drill out the sprocket, and tap it for a set screw that will clamp it to the flat spot I ground onto the motor shaft. Way less work than my original plan!
And on top of that, we finished the cleanup of the cemetery sign we were carving for a local sign shop. They want us to paint it now as well, black and white, so we'll tackle that next week when the games are delivered.
8)
JWO






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.

8)
JWO






Tuesday 25 June 2013

Glass, glass and more fiberglass!

With the styrofoam molds ready for epoxy and fiberglass, the only thing left was to start. All 4 of us worked on getting the cloth wet out and applied. We actually started with epoxy mixed with cabosil, as a thicker gel coat. This will hopefully fillet any deep cuts, allowing the fiberglass cloth to conform a little easier.
This was the point that I realized I never sprayed the foam with a mold release! I'm sure I'm going to pay for that later. At least the epoxy will be way stronger than the foam, so it shouldn't be the end of the world. Or that's what will help me sleep tonight!
We got one mold completely finished with 3 layers of cloth, for a minimum thickness of around 1/8" thick. I ran out of epoxy on the second mold after 2 layers. So I'll head to the fiberglass place in the morning to get one more gallon. It sucks a little as I wanted to demold them both in the morning, but it's all good!

I was able to get the mdf backer boards cut for the bases as well. We also got all the 2" stove bolts installed and threadlocked. Today was a great day in terms of progress, hopefully tomorrow will run smoothly as well!

-----------------------------------------------------------


I have been receiving some friendly banter from my fellow creative friends, Dan Sawatzky and Doug Haffner about our friendly "sign build off" competition. The ribbing is well underway now, with Dan leading the charge on his rendition of our "Institute for the Study of Mechanical Marine Life" sign. I can't remember if we actually all placed a wager or not, but it will be fun.

 This is Dans render of the sign he'll be fabricating. Looks pretty nice!
However, there is something that I REALLY like about Dougs rebuttal, but I just can't seem to put my finger on it. Hmmm.........it might the composition.

 I won't be giving away any details on our entrance piece quite yet, as I would hate for Dan, and Doug, to put down their tools and find employment in a local donut shop :)
I would, however, buy my coffee from them if they did, but I would watch them like a hawk when they made it!

Let the games begin!
8)
JWO



Monday 24 June 2013

Styrofoam Mountains

Well, the complicated parts of the Coors light game didn't solve themselves at all! Which meant I had to.
The base finally got all of it's hiccups ironed out. I used the cylinders that were placed along the imported chain track to make sure the little man wasn't going to bind on the inside of the mountains.
I made the Coors logo to the right size and thickness of what I would be using in real life. Once I had the logo as a 3d model, I was able to cut it out of the mountain. This way, when I actually make the dimensional logo, it should key right into place!
The other integral portion of the base is the little party cabin. The hiker dude will enter the cabin, and it will light up with silhouettes of people having a party inside!

I also used the mountain to cut out the cabin. I don't actually need the whole cabin, just the parts outside of the mountain. I will export the building into Lamina Design and flatten it out for cutting out of sheet styrene. The door will get located once I am positive it's going to work as planned.
This is the underside of the game, and you can see the chain layout. It was imperative to have all of these parts in the computer to make sure of the clearances.

 Once imported into Aspire, I overlay-ed the original design vectors onto the 3d model.

 I recessed the X's for each checkpoint, as well as recessed the logo in the center of the game. I also used the create shape tool to add small pointed domes where all the locator bolts will go. Once we remove this from the mold, the small pointed domes will actually become small "countersunk" divots that will let us accurately drill into the game. I also added a pointy track that will become the opening for the post that drives the hiker around the game.


With the extended Z-axis travel of the geometry, as well as a pretty tight stepover, the 2 game bases were on the machine all day Saturday.
Once the layers were glued up, I was able to get the edges screwed and glued together. Were doing this as a negative mold. This way the detail like locator holes, logo holder, and the cabin foundation will get cast exactly like the original geometry. It was cheaper, and faster in the end to make 2 styrofoam molds, which will be destroyed at demold time, versus one styro form, and ripping a master mold from that.
Soon the resin will flow!!
8)
JWO



Thursday 20 June 2013

Redneck Banjo Update!

While I await materials, and the complicated parts of the Coors Light game to miraculously solve themselves, I came across the TV ad for the redneck banjo we made. Quick turn around on their part!


A little crazy, but I do love the banjo!
8)
JWO

Tuesday 18 June 2013

Lazy Hikers don't walk, they ride the chain!

Well, it's been like smashing my head against a wall on the Hiker game for Molson/ Coors. The design was based off of early sketches and collages of what it was to look like. Originally the reference was an icy, almost vertical wall, but we had to adjust the size and angle for transportation logistics. So as the 3d model was massed and ready to go...........a revised drawing came in with enough changes to head me back to the drawing board. We'll still drive the hiker with a chain, and he'll still have the same number of checkpoints, but now it's a grassy hill, with the Coors mountains in the background. They also want the "Coors Light Mountain Survival" logo on the flat portion the man will travel. This messed up the existing chain layout. So the last few days have been spent at the computer again, incorporating everything that has changed. It's one of those things that by moving one piece, just a little, it has a chain reaction to the rest of the pieces! Oh well, we do love a challenge!!
I was able to re-purpose the gear sprockets, and move them to their new location on the board. The Logo is offset to the right to allow for the mountainous hill that will hide the hikers return to the starting line.
I drew a grid plane in Hexagon that will become the base mesh of the game surface. The cylinders, and the belt shape that runs up the side and the top, represent the volume of the little vagabond hiker that will endlessly hike this hill. This is so when I mass the terrain, I can be sure he will have ample clearance to get around. I exported the logo outline from Corel as a dxf, and imported it into Hex as a position holder. The horizontal and vertical lines were used as alignment reference. It's crucial that everything be as accurate as possible at this point! The same went for the track and sprockets. All DXF's, exported and aligned to the base mesh. I will eventually do the same for the little "X"s as well.
We have been busy cutting tons of stuff for the other sign shops in the area, so I'm not as far along on this game as I would like, but we will be heavy into the fabrication come Monday when it's all drawn and the layout clearances all work together!
8)
JO




Monday 10 June 2013

Trivia Hiking!

Our current build is a table top game for one of the large brewery companies here in Canada.
Basically they wanted a cool looking system that would have people answering trivia questions.
This is a VERY basic massing model, and the real version will be quite a bit more detailed.
The concept is that a person would answer questions, and upon getting the answer correct, the host would press a button, making a little hiker man ascend to the first checkpoint. This process continues until he reaches his destination cabin at the top of the hill. Once inside the cabin, he'll track through the mountain, unseen, until he pops out the base camp cabin at the bottom of the hill, starting the game over. Each checkpoint will have a light that comes on when he gets there. The electronics are dead simple, so there will be very little to go wrong, as it travels around the country. It will also be encased in acrylic, to avoid the temptation to grab and touch elements on the hill.

We have decided to drive the hiker with a #25 roller chain, locked into a track, under the base.

I wasn't able to get any in-stock chain, but the bearing company I ordered it from was able to provide the chain and sprocket specs for me. I turned this into a 1 to 1 scale drawing so I could figure out exactly what the length and distance for the track needs to be.
Using the sprocket drawing I created, I was able to get a lock on how the track would travel around the game base. Because the chain can only flex in one direction, it's critical that the track up the mountain be as planer as possible. We'll landscape around this fact, making the base a little more interesting than in the massing model. We're running the whole thing off of a low voltage 12v system, so it will also be very safe!

This is going to be a little design intensive for the next little bit, but it should be a lot of fun, times 2 games, equals even more fun!
8)
JWO


Friday 7 June 2013

The Power of the Beaver!


 Machining of the beaver plaque took around 2 hours total on our little Techno. This included roughing with a 1/4" ballnose, finishing with a tapered 1/8" cutter, text cleanup, and finally a cutout pass.

One of the processes I taught in Indiana was the text cleanup process that removes the jagged edges around text and components. The jagged edges can be the result of the resolution settings in Aspire 4 when the model is first created. Our little Techno is moving pretty quick, considering the z axis is actually moving up and down due to the underlying texture that was applied in the model.
The cleanup pass was done with a tapered 1/16" ballnose cutter. The difference between the bottom text vs. the upper text is night and day.
Due to the beaver head being quite thick, and keeping the whole relief in a 2" thick slab of HDU, it left the rest of the plaque a little thin. Not really a problem, as I had always planned on using 3/4" MDF as a backer plate. The weight of the MDF made the plaque feel really beefy! It also allowed for easy mounting to a wall. (Hopefully they WANT it on their wall :)) We used a urethane glue and clamped it over night.

Once the glue had dried overnight, and some little parts were further cleaned up, we got a couple of good coats of exterior acrylic primer applied.
 The entire sign was then sprayed out in a very shiny brass color. When we apply the glazes, the base color can get pulled back quite a bit, so the brighter the better right now!
Most of the metallic colors we use are the Rustoleum Metallic Accents paints. Readily available, and amazing metallic for a water-based paint. The first glaze coat was done with the classic bronze, and once that was dry, the rich brown was added for the final darkening.
Once the 2 glazes has dried, the plaque looked great!

 I decided that I wanted to add the polished metal look to the text and borders, just to add some bling!
This was done in our usual way with the metal powders buffed over gloss black. And as this is in inside sign, I didn't have to clear coat any of the metal. The Pearl-ex powders are guaranteed not to tarnish, so any indoor handling wont leave finger prints. Woo-Hoo!

We presented the plaque at lunch while we were at the little restaurant, and I do believe that they loved it. It will be interesting to see where they hang it!
8)
JWO


Thursday 6 June 2013

Canadian Sign Embassy

I mentioned yesterday that we had given a plaque of sorts to Colloms General Store, crowning them as the Canadian Sign Embassy, and this was the plaque we made and presented.

The first order of things for me was to create the beaver! I did a google image search for beavers, to get a feel for what he should look like! I like to go to 3d as quick as possible. I think that it might have something to do with my weak-ish sketching skills, but massing it in 3d helps me get a feel for how the whole thing will work together.
Working in a low resolution state, and occasionally smoothing the model, lets me get an idea of how the figure is proceeding. Low res for the general shaping, and smoothing for the tweaking.
I modeled most of the beaver with symmetry applied. This keeps both sides exactly the same. Sometimes it can get out of control if I don't have both sides the same. Once I was totally happy, I turned off symmetry, and started to distort the left side of the model, so he had a bit more character.
The eyes were simple spheres, with the pupils extruded inwards a little. I was able to just build the right eye, then mirror it for the left, and distort it to fit visually.
I created a single half sphere and flew it in on the right, mirrored it over, and distorted it as well.
The teeth were then added from a simple cube primitive, shaped to fit. Both teeth are actually one single mesh, but I could have easily made a left and right tooth, and just pushed them together. Once imported into Aspire, the software treats it like one whole model. If we were 3d printing this character, we would have to try and keep the mesh as single as possible. Glad were not doing that!
I decided at the last minute to add a winter toque, as it can be stereotypically cold all year long in Canada :)

I drew up most of the vectors, and imported them into Aspire. I used the 2 rail sweep to get the outer ring to have a slight dome shape. I made a textured bit map a while ago that I use for a rough style texture. This was used to give a little texture and interest to an otherwise boring surface.
The center circle was dished out to allow a little depth for the beaver model.
Once the beaver model was imported and located, I decided to add some "sun rays" radiating outward. This helped the beaver head from looking to small in the recess.
Finally the text went on. I decided to use a casual style font for the lower portion of the sign. Almost like it was added as a last minute decision, without regard for the "official"-ness of this particular government symbol.

Next step--------------Techno cnc!
8)
JWO