one of many of donald judd's untitled works

This week we were asked to make something "big" using the CNC machine.

Like the cardboard from WEEK 02, I wasn't a huge fan of OSB, but then I thought of Donald Judd's work - much of wich is made from the super simple sheet material of plywood. I thought it would be cool to recreate one of his pieces with OSB to have for myself.

proposed "big" thing : djudd's piece in osb

The particular piece I was interested in measured about 4' x 4', so by scaling it down just a bit, it could fit into our 4' x 8' sheet of OSB.

However, before cutting the actual "big" thing, we were ask to make test cuts. I paired up with Morgan and Yuxuan, and we divided one full sheet into four quadrants, into which we could each test whatever we wanted according to what we were going to make.

From the image of his piece, you can see DJudd doesn't deal w highly complex joints, so I wasn't interested in using joint cuts, etc.

mastercam file :

inner shallow cut vs outer complete cut (with "onion skin") :

Instead, I made a shallow cut into both square faces, in order to more easily place the side pieces - this also means you wouldn't see the thickness of the material, just a simple square face with a circular cut out.

I basically used the test cut to make an even more scaled down version of the piece in order to test whether or not the shallow cut would work or if I would have to rethink the whole thing.

I also wanted to test an "onion" skin vs placing tabs, which are harder to get rid of / clean up post milling.

tool set up :

the tool set up for this kind of file is pretty simple / straightforward because it's really a 2D file.

I used a half inch tool to make my shallow cut, which had to be inset the thickness of the material which was just below .5". (I could have used the quarter inch tool, but then I would have had to go around the curve twice to make up the material thickness). In order to make a shallow cut, I went to cut parameters and changed bottom of cut to be .25 rather than 0.

I used the quarter inch tool to make all of my cut outs. The file took a while to cut because we used a 1/8" stepdown (rule of thumb is your stepdown is half the diameter of the tool you are using). Again, we could have used the half inch tool, but this means you cut away more material and can't cut smaller things. In my case, this wasn't an issue, but I did want to preserve as much material as possible in order to avoid moving parts.

In order to add an onion cut, you change bottom of cut to be .005" rather than 0. Before we cut all of our test pieces, we did test this onion skin. If it wasn't enough and the pieces did move, the onion skin would have been for nothing.

osb splintering :

Even though we used a downcutter, the OSB splintered, which is sort of unavoidable because OSB just isn't a super nice material. I wasn't too worried about it, you can easily clean up these edges by sanding or clipping off splintering w a box cutter.

The images below show the clean up results post milling :

before trimming edges :

after trimming edges :

before sanding :

after sanding :

easy assembly due to shallow cut:

glued and clamped:

finished "test" piece : ?

- - - - -

I actually was pretty content w my test piece, and I am excited to make an almost 1:1 OSB replica of Judd's untitled piece.

After meeting with Paloma during office hours, we discussed I should try to use this make something "big" assignment to make a prototype of my conveyor belt. To be clear, I am interested in making my conveyor belt out of some metal material, possibly aluminum, but OSB would be a cheap way to test some very basic things...

Ultimately, I decided against this. I really did want a rip off Judd piece for my apartment, but I also felt the poor quality of the OSB wouldn't be too helpful in terms of a prototype. Having said that, I do hope to start prototyping by the end of the week / beginning of next week possibly in aluminum but I am also considering acrylic.

djudd box (almost) 1:1 :

Not too much changed in scaling up Judd's piece.

I wasn't able to make a 1:1 replica because Judd's piece is exactly 4'x4'. Having only one sheet of 4'x8' meant I wouldn't have material for the edge pieces. Thus I scaled down in order for everything to fit on one sheet.

I will say the warped / curved quality of the OSB was harder to manage at this scale, but nothing a couple of clamps couldn't help remedy.

updated file included a new mitered edge :

Before making my file, I did decide to remeasure the material using calipers. I've had enough negative experiences assuming material thickness to know better! And the thickness had in fact changed from .46" to .44". Might not have been a big deal, but I did want clean edges, especially if my object was SO simple, it could at least be done as clean as possible.

Along those lines, I decided to miter the edges. I noticed my test piece didn't look as nice as it could have because the edge of the box didn't meet in any particularly special way. I was worried the pieces would move because I would be applying another toolpath after they were cut out (with onion skin). I chose to surface the mitered edges AFTER they were cut out because since the surface was so small, I needed to use a small tool and I didn't want to do this without having removed some material to be easier on the .25" toolbit. Thankfully, the onion skin was thick enough to hold the pieces in place while the final toolpath created the mitered edges.

The mitered edges and the shallow cut on both faces made for a significantly easy assembly. And because I remeasured the OSB, everything fit really well. I was pretty satisfied with the result.

tada :

I also decided not to sand the surfaces. I do actually like the darker color of the OSB. When I made the test piece, I realized the OSB got a lot lighter. I also kind of like the stamped text... In the spirit of Judd, not trying to hide what the material is.

original :

Here's Judd's piece again. Idk, I do like my rip off OSB version. Looking forward to putting it in my living room.

in my guest room :

here she is - happily decorating my guest room along w other models and nice objects :)

Files :
Dropbox