First Project: Portal Ornaments


(John Clark) #1

Just a quick first project to get things rolling. This is a pair of ornaments with the Aperture logo from the Portal video games. They are made out of bloodwood with a thin maple veneer glued over the top to provide contrast. I am pleased with the results for a first project. I am still getting the hang of the software and the machine itself. Lots of ideas.

Any hints on getting a more consistent cut with Vcarve?

John


(Clifford Land) #2

general ideas, hope these help. these two ornaments seem to have the same irregularities in the same places. i would check your source art work for extra nodes or jogs. check that straight lines are not replaced with some weird curves or arcs. make sure you have a good sharp bit. you will also find over time that some woods are better for fine details than others.

good luck and happy chip making.


(Tchad Rogers) #3

Can you add some more details about how you cut these, and what irregularities you see that you’re trying to fix?

I see minor tear-out, probably caused by an up-cut bit, and slightly imperfect lines, which could have lots of causes.

What bit did you use, and what were your feeds and speeds?

Was the veneer applied before cutting (I assume…), or were the two pieces cut separately?

It sounds like this was a first cut on a new machine… have you performed the usual checks, like squaring the machine, checking set screw tightness, and cutting a circle-square-diamond to verify everything is working correctly?


(Tchad Rogers) #4

btw: very nice job, that’s a pretty awesome first project, and welcome!


(Adam X) #5

So here we are again, it’s always such a pleasure.

In addition to what the other two folks mentioned, validate with an angle gauge your vbit’s real angle. Keep in mind that if you’re using carbide-create to make the toolpaths, it reverses the angle, so a 60degree vbit needs to be specified as 30 degree bit.

When it comes to fine detail in wood, an old trick I’ve used it to soak the parks in thin CA as you’re gluing the veneer to the base wood. CA once hardened has a much finer “grain” structure than wood and can take better detail. However, be aware too that if you do that, you’re now cutting a mix of acrylic (essentially) and wood, so you’ll need to slow down your feeds and speeds vs what you’d use with wood.

Remember when you tried to kill me, twice…


(John Clark) #6

I used the default feeds from Carbide when I set up the bit:
DepthPerPass: 3.838 mm
Stepover: 5.715 mm
Feedrate: 582.126 mm
Plungerate 145.531 mm
RPM 7639 mm

The logo design was from an SVG I grabbed online, so there are probably some imperfections here and there. The veneer was glued on prior to cutting (24 hours drying time). All bits are new from Carbide.

My quibble with the cut was that the V-carve “sounds” like it is aggressive (if that makes sense). I wasn’t sure if this was plunge or feed or a combination of both. As I said, this is my first CNC project so I figured I would ask.

John


(Craig) #7

Look at your vectors in node editor and see if it reflects your end result. You can clean up the vectors in node editor.

If it sounds too aggressive slow down plunge and feed rates.

You can create two toolpaths by duplicating it in VCP and editing one to do a light finish pass full depth. To clean up the vcarve.


(Tchad Rogers) #8

Can you post the SVG here? We could look at it and see if the wandering lines are in the SVG or have something to do with your machine. If you still have it, post the VCarve file as well.

I assume you loaded the SVG into VCarve, then created an outside profile path (with a .25 or .125 square end mill) to cut them out, and a V-carve path for the triangle sections? Assuming that is correct, did you cut the v-carve first, or the profile (cut-out) first? Did you create holding tabs in the profile path, and if so, what were your settings?) I ask because if you profiled first, and the tabs were insufficient, you could have the ornament wiggling a little during the v-carve tool path, causing the wandering lines… if you v-carved first, then it’s a moot point…

One point that I noticed today that I didn’t notice previously, is that the circle cut outs are pretty good… it seems less likely to me now that your machine has a configuration problem (loose pulley set screw or belts).

The V-bit that you used was a 60-degree, right?