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.

Wednesday, 28 August 2013

Lot's of R/C!

With the Zerby Derby kids show well underway at the shop, things are starting to pile up quickly!
 There's new cars to be made, old ones fixed, paint to touch up..............
One of the newer vehicles is this utility truck with an r-c robotic arm. We didn't make the arm, but who-ever did, did a great job. It has a total of 6 degrees of freedom, so it will serve them well on set!
We got the ferry hull de-molded, it was still a bit of work to get the foam off, even with the release agent applied, but the form was great! There were some little spots, but no big deal.
 It pressured washed up pretty easily.
We mixed up a thick batch of epoxy and cabosil and spread it thinly over the hull portions that are above the waterline. This filled all the small pinholes that get left over from casting into styrofoam.
Tomorrow we'll sand it down, put a rubberized texture on it, then this part should be ready for paint.
Due to the size of the ferry, versus the water depth on location, they've decided to puppeteer the ferry around, instead of adding motors and propellers. The loading ramp will also be puppeteer-ed. We were going to install a 12v linear actuator, but the time to move the piston 12 inches, is around 30 seconds, WAAAAY to long for television!

While that was being tackled, I finished the small changes to the pickup truck file, and got it on the Techno. We're cutting the final mold from some pretty dense tooling board. Same stuff as last year.
By the end of the day, the first 2" layer of the truck was rough and finish cut, and the 2nd and 3rd layers got rough cut. I'll run the finishing pass first thing in the A.M.
And while all that was happening, Jody was able to cast up, and base coat another order of 30 beer tap handles. These will get a streaky dark "grain' applied by a rough paint brush, then sprayed with a wood color tinted clear-coat.
Man, were running out of room..........again!


Monday, 26 August 2013

Waiting For The Ferry Is Always Slow!

I got quite a bit done on the ferry character for the television show were working on. Most of it was done over the weekend. The first step was to nail down a basic design for what the ferry was supposed to look like, and how it needs to function.

The plan and side elevation were quickly drawn to size in Corel, allowing for the space they need for 2 vehicles to be carried around on the water. The control tower will get the standard rc eye-balls that all the vehicles have. I also wanted to add a Sou'Wester hat to the ferry boat, for a bit of whimsy. I don't know if it will actually get added though.

The vectors were exported out into Hexagon, for extruding the hull section into a 3d object.
It really took no time at all to build the 3d hull form, working from the imported vectors. And as they were drawn to size in Corel, The hull was to size in Hexagon.
The last step in Hexagon was to split the model out into sections for machining in Aspire

 Our Techno milled away the styrofoam, while I vacuum formed a test pull of the new mold for the pickup truck.
Perfect clearance for the eyes to move freely! Woo-Hoo!
After messing around with the truck for a little while, the styrofoam hull was ready for cleanup and assembly.

Finally, a boat shape! As usual, it was followed by the phrase "That's a little bigger than I thought :)"

This morning I picked up the epoxy resin we'll be using to fiberglass the final shape.
The styrofoam mold got brushed with 3 liberal coats of resin. The more the better when making a 1 off mold this way. As we'll have to sand the entire finished piece to get rid of the styro texture, the thicker gel-coat will give is a buffer so as not to sand into the cloth. The tight inside corners were filled with epoxy and cabosil as a thickener, to aid in the 1 1/2 oz. fiberglass mat rolling the edges better.
Hand layup of fiberglass can be painfully s-l-o-w! But by the end of the day, the mold has 3 layers of cloth in it, and two 1x3's for additional strength. I ended up throwing my shirt out at the shop as it was covered in resin and glass, and I became Tarzan for the drive home. However Jody refused to join me in my shirtless adventure, leaving me as the only topless driver on the road.

Friday, 23 August 2013

Can I get a Light....House

The show were currently working on, Zerby Derby, requires a new lighthouse for the townsfolk cars and trucks.

Phil, the director and series creator, sent me over a couple of images of his idea for the lighthouse.
Nothing complicated, a pretty straightforward design.

The drawings were all done as 2d vectors, that would eventually get cut on our Techno, from 1/4" PVC. PVC is the first choice for this. It holds up well outside, is light and easy to cut, and a dream to paint!
The main tower was pretty simple, especially with our angle jig for routing miters. And as always, I use masking tape as a hinge to hold the pieces together, and evenly. I always tack the seams with CA glue to hold them together while I flood them with VC1. The CA works great, as I can't leave the tape on when I flood the joints, or it wicks under the tape and makes a crazy mess!
As in the reference photo, I added a thicker base portion to the lighthouse as well. Most lighthouses have doors at the bottom for the lighthouse keeper to get into the building. As the townsfolk in this show are cars and trucks, they don't really need to get into the lighthouse. So this door will actually be a hatch that holds a fake joystick to "move" the light around at the top. The joystick will be operated by one of the construction vehicles that has a robotic arm. In reality, the light will be rotated by hand, out of frame, from the back of the lighthouse.
I went with a chromed-out 4x4 offroad light for this. Simple, industrial, and weatherproof!
While I was working on the lighthouse, I also had the new truck mold machining on our little Techno.
This was laminated the exact same way as I did last year. Normally I glue my layers up after they're cut, and off the cnc. But for these molds, I want the cnc to over-cut the seam, milling off any glue that squeezed out during the lay-up.
This mold is being done from 18lb HDU. Once we pull one test piece for approval, we'll re-cut the mold from 60lb tooling board.

It was nice to have both machines cutting away! The little tabletop Techno was an amazing purchase, as it frees up our big machine for 4X8 sheet stuff like the lighthouse!


Tuesday, 20 August 2013

No Sign Competition for Me :(

I have tried to stick to the "A little here, a little there" adage on our Institute sign for the competition we're involved in, but sadly there isn't any time left in the day for me anymore. And I'm a huge believer in doing what you love, and I know that if I'm not enjoying doing the Institute sign, then I shouldn't be doing it. I will finish the sign, but the competition will be long over. It kind of stinks a little, but I really am running out of time, on all of our projects! The vacuum former was a bit of an unplanned event, I was hoping to tackle it in the slower winter months.

The last little bits that got done to the octopus was the body paint job. I base coated the body with the MM copper paint.
I decided not to use the MM copper patina at this point, as I don't like the uncontrolled way it gets applied, especially because I want varying degrees of patina. So I went with a verdigris paint/glaze mixture.
A lot of the vents, and other small sections got picked out with varying tones of Rustoleum Metallic Accent paints.

I wanted the bottom of the octopus to be very patina-d. The hull shape, and prop guard keel were based loosely on the very early transoms of steam ships, and I wanted the texture to match. This was iron paint, dusted with iron powder. The powder goes almost black and rough like very old rusty metal. The overspray from the rusting solution really pushed the copper paints age that I used on the main body, so the whole underside looks in pretty rough shape, absolutely perfect for this!

So sadly I have to shelf our sign for the time being, but I will start it again soon, as it's way too cool no to finish!!!

Thursday, 15 August 2013

No time to Breathe!

Things are a little hectic right now. There is lots happening, most of which occupies all of my work and spare time. So essentially there is no spare time!

Last year at this time,we worked on the children's show "Turbo Town" That was the working title of the show. It has been changed now to "Zerby Derby" I do believe the stuff shot last fall will air this fall, while they shoot season 2.

We don't have near the amount of work as last year on this, but there is still a lot to do, and in a relatively short amount of time.

This was one of the casualties of last years filming! Pretty rough job being a remote control car!

Last year we machined the mold for the trucks, but in a last second, production design change, we had to scrap our mold and finished trucks and use the hand made body filler mold that they already had.
This year, everything has been better thought out, and we will again machine a new truck mold. I can salvage some existing geometry from last year, but it's ultimately a complete re-do.
There will be some new characters this year, including this "body donor". This kit will be modified to suit the needs of production, as well as a complete color scheme re-do. In fact, I think we are doing 2 planes. One with animatronic eyes for the close up, and one with fixed eyes for flying.

There is also a utility truck, and a ferry to design, machine and build.

In order to meet the production requirements, we needed a vacuum former. Last year we were supplied a very under-powered little guy, that was pretty much done by the time we were finished the job. This year, we needed something a little more rugged and powerful. Believe it or not, there is a huge gap in the vacuum forming machine market. It's either hobby grade, or serious industrial grade, with next to nothing in between. We found a suitable machine on line, but their turn around was at least 6 weeks. I didn't really want another "project", but I wanted a vac-former. One of my guys that works for me occasionally is a bit of an engineering genius, and volunteered to build it for us, so I didn't have to. He drew most of the files for me, and I just ran them on the cnc, around other stuff. The above picture is our 22"X22" vac-table being riddled with 1/8" holes on our little Techno.

It didn't take very long to get the parts assembled for the table at all.

As the steel frame was starting to get quite heavy, we decided to add linear actuators to raise and lower the clamp frame. As it most probably will be Jody or Anna forming, it can't be too heavy.
So far, it seems pretty slick! Tomorrow the final wiring will get done, then it'll get a coat of paint!


Thursday, 8 August 2013

A little more body is all I need.

There hasn't been very much building at the shop this week, I'm doing a fair amount of 3d work, but our vacuum former is almost done! Just kinda waiting on heaters.

I did manage to get the octopus body built, but it's little tiny bits here and there.
As our big Techno was cutting Vacuum former pieces, I cut the octopus on our tabletop machine. I really like this machine, probably because it doesn't take as long to clear the crap of it when I need to router something!

I didn't get any progress pics of the assembly steps to the octopus, stupidly enough, but I did get pictures after it was all put together:

Most of the final finishing was done at home, between emails, and such.

Soon, soon there might be a finished contest entry from us!

Friday, 2 August 2013

Stupid Octopus!

A lot has happened in bits and pieces on the octopus over the last little bit. My time to work on it gets smaller and smaller as other projects come into the shop. Our next job has us building a vacuum former to pull a bunch of parts for that.
All 160 pulleys got their patina paint job on them. As well as the bronzed sections that hold them together.
I was really hoping not to have to run the pulleys through the lathe, but it quickly became apparent that it needed to be done :(
It's a little hard to see, but every pulley assembly got a little guide pin installed. I hope I get to use it, but the time is quickly running out on the deadline, but it's there if I need it.
The tips of the tentacles got cut as well. I have no idea how I only cut 71/2 of them, but I did. So one more to cut for that tomorrow. I also need to add a bit more to it to make it look a little bit better, so I'll cut that as well while I'm at it.
The turret gear plate that all the tentacles mount to also got machined. 3/4" pvc for this bad boy! The holes around it are for screwing and LED lighting.

I also built the mounting arm assembly for it as well.

As the pulleys don't actually turn, and are strictly decorative, I used hair elastics for the belts. They hold the tension really well, and look nice and beefy.
This was the single most frustrating assembly job ever, in the history of frustrating jobs ever. Each pully assembly alternates all the way down the line, and the belts have to go on in a certain order. I actually had to make miniature belt pullers to assemble this stupid contraption. As it usually goes, the first arm took about an hour to assemble properly(on goes the belts, off goes the belts, on goes the belts in a different order!) The last tentacle took around 6 minutes. Another job I'm a skilled craftsman at now, and another skill I'll never use again!

But in the end the assembly looks crazy awesome. A ton of detail to look at. I have to stain the white of the pulley grooves, but other than that these guys are almost done! I'm going to work on them on Saturday, and hopefully get to machining the rest of the body!