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.

Tuesday 1 April 2014

Cutting water on the Router!

Our next, short run gig, is a small job for an associate I used to work with years ago on Zoom.
He has an install in a museum in Japan I believe.

Basically he just needs 3, 18"X18" sections of clear plastic that will represent the waters surface in a display.
This will be vac-formed for sure, and MDF fits the bill perfectly!

The water surface is a total of .4" from peak to valley, but I'm going to machine from 2 layers of 3/4" MDF to discourage any warping that would occur at a smaller thickness. 100 lbs of weight, and some clamps to prevent sliding, was all it took to get my slab.

The file was supplied to us, and we cut it in under 20 minutes with a 1/2" ballnose cutter.
A couple of light coats of water based urethane was used to stop the MDF furries from rearing their ugly little heads, followed by a quick sanding. The mold was made oversized, and will get put back on our Techno to trim the pull to the right size.
We have been using a "new to us" primer, that I absolutely love! It's a polyester primer, that gets catalyzed with fiberglass resin hardener. Smells terrible, and you MUST use a respirator when spraying it. But man-O-man, I love this stuff! Sprays on nice and thick, covers small seams, and is sand-able in less than an hour! I sprayed around 300ml onto the surface so it would be nice and thick, and eliminate any tooling marks. The whole thing was then finish sanded, and buffed with wax.

I picked up the .125" PET-G that were going to use, so were ready to pull first thing in the AM. We don't have to do any scenic to the panels either, the client will do that part.

I'll do a test pull tomorrow morning, just to make sure I don't need any suction holes drilled through the low spots. But I think it'll be good!
8)
JWO




5 comments:

  1. Thanks for the update. It's looking good.

    ReplyDelete
    Replies
    1. what?! Who's this?!...........Mom...................?

      Delete
  2. Hi Jamie. What ratio do you mix the polyester primer and fiberglass resin using?

    ReplyDelete
    Replies
    1. Hey Mal!
      It's actually a product called Slick Sand. It's a cross between Bondo and fiberglass resin, so it's got the consistency of latex house paint. The gallon comes with 4 tubes of hardener, so 1 tube per litre approximately. I mix it a bit hot, cause it would suck if it didn't harden :)

      Delete
  3. Thanks Jamie. Just soaking up info.

    ReplyDelete