[Pplug]

This post was originally in the teachers hang out, but I have been asked to post it here as well.

Last year our technology department built this monster of a CNC machine.

X travel: 44.8"
Y travel: 44.8"
Z travel: 9"

The frame is made from 6x3" 3/8" cold rolled tube steel welded to 2" tube legs and 2" angle iron for the supports and table. The gantry is formed from 7x2" .25" tube steel and weighs approximately 150 lbs with the z axis attached. All axis have 20mm supported linear rails, 5mm pitch ballscrews, 387 oz/in motors. The motor controller is the awesome Gecko G540 and a 12 amp regulated power supply. The spindle package is a typical 2.2kw Chinese spindle with Huanyang inverter. Tying the whole package together is an old Dell gx270 workstation running xp and mach3.

So far after working out a few kinks, the router is running like a champ! We have cut several different projects including a large sign using a 120 degree 1.5" diameter V bit. it bogged through the material incredibly well. As soon as we straiten out some software usability issues with Mach 3, we would be able to have students run and produce their own projects!

For more pictures and to see some of the build progression of this machine check out: http://www.minisink.com/~rbudd/

[PaulRowntree]

This is a fantastic opportunity. My son's shop class (high school) has a commercial unit, but the expertise has been lost through lack of use. Do you know how the students will be taught to use this tool? The learning curve is steep, with a lot of aspects. I can imagine that some students would fall in love with the idea, while others would fall by the wayside. The tough part is managing both groups.

Bravo!

[Pplug]

This is a fantastic opportunity. My son's shop class (high school) has a commercial unit, but the expertise has been lost through lack of use. Do you know how the students will be taught to use this tool? The learning curve is steep, with a lot of aspects. I can imagine that some students would fall in love with the idea, while others would fall by the wayside. The tough part is managing both groups.

Bravo!

We actually have 3 cNC milling machines in the shop. The trick with teaching any kids especially middle school kids is to break each part of the project down small steps. Students these days need instant gratification so we start using CNC on a simple engraving project using a Roland M DX – 40.

The next project we do are marble mazes. The students make their maze in AutoSketch then import a DXF in to go Galaad. Galaad creates the toolpaths and actually runs our small techno router. We can now also use Galaad to generate toolpaths for our large CNC the "green machine."

One of the drawbacks and also the strengths in our program is that we have three different routers with three different interfaces. It's difficult because we have to teach how to use three different machines but it's also useful because it teaches kids more of the concepts than more of just the steps. By teaching the concepts kids can adapt to different cNC controllers.

We are in the process of purchasing 10 licenses for vectric's aspire software and we will probably be using that software more than Galaad to generate toolpaths for all three machines. The interface is much much easier so the complexity and scope of our projects can increase.


Keeping students interested in the project is really difficult it's usually either hit or miss. If we can keep around 80 to 90% of our students interested in the project then we will keep that project. if the students don't like the project, well, then there's always next quarter.

This is just a side note but this entire message was dictated using my iPhone 4S pretty cool huh?

[Pplug]

Here are the archived posts from the technology departments website that are no longer easily found. They show some of the build progress for our "Green Machine". There are pictures but the videos are hit or miss.

cnc Update!

CNC Assembly

CNC near completion!

Manufacturing Technologies

CNC Machine Fully Functional!

Completed Signs

LeCroy CNC Donation

CNC signs cont.

[LazyMan]

Nice job!

How fast can your machine rapid before ball screws start to whip?

[Pplug]

Thanks, we can ramp it up to 280 ipm. We could push it higher but then we would have to slow the acceleration. Screw whip is not really a problem until we get over 300 ipm. We have done quite a bit of cheap crappy pine and the router blows through it with a 1/4" bit .25 deep per pass at 150 ipm. It impresses the hell out of the kids!