Please welcome... "Contraption 1"

[JRoque]

...and try not to laugh.

Contraption 1

Let me try to describe it: As you can see, it's got more Home Depot in than NSK. A few pieces of wood and MDF form the temporary frame. I'll limp along like that until I fill my piggy bank again and buy the 80/20 aluminum frame which will be 40" x 40" x 15", gantry style.

The power supply, not shown, is a lab HP 60v/15A. The 3 axes drives are Applied Motion 3540m. The steppers are NEMA 23, +180oz from Slo-syn and Bodine. The rails are THK HSR25, 24". The screw/rail combination on X & Y are special order Thompson with Nook nuts, 27" travel, .2 pitch. Z axis is a Daedal 8" travel. The spindle is an old Precise 45K RPM that weighs a ton. Software control is Mach2 - awesome stuff.

That's it. It's my 1st attempt after about a 2 month spending and reading spree that made me end up collecting a bunch of old stuff from eBay that doesn't plug into each other. I had to use "Mr. Glue", my hammer, to help the pieces match.

Later,
Julio

[duluthboat]

Well done Julio, I especially like the bar clamp. Nice little basic machine.

Garyy

[JRoque]

I had that clamp in there while tightening the screws down.. I forgot to take it out. That's it, I can't be a surgeon and be leaving stuff behind.

Here's something else I've been working on.

ZZTouch

It's a way to automatically set Z to exactly 1" above the material to be cut. It works by touching the spindle tool to a sensor, which is nothing more than a piece of copper connected to a pin on the parallel port. The Mach2 macro lowers Z until it touches, slowly backs out until it lifts off the sensor, subtracts the sensor's depths and marks that as zero. It then moves back to +1".

The idea is to be able to use different material heights and tool lengths or how far they're inserted in the chuck and set all my cuts to 1" + the depth I want to cut. Am I off with this idea?

Thanks,
Julio

[duluthboat]

JR, the link isn't working.

Gary

[ynneb]

[quote]It's a way to automatically set Z to exactly 1" above the material to be cut. It works by touching the spindle tool to a sensor, which is nothing more than a piece of copper connected to a pin on the parallel port. The Mach2 macro lowers Z until it touches, slowly backs out until it lifts off the sensor, subtracts the sensor's depths and marks that as zero. It then moves back to +1".[quote]

It is true the link doesn't work, but I have a question anyway.

If you change the tool in the spindle then how can you set the Z zero, since there are different length tools?
This is something that I would love to work out. How to make an automatic Z zeroer.
How is it done on professional machines?

[buscht]

Benny, most professional CNC routers that I am familiar with are setup offline. Meaning you put your tool into a preset toolholder, measure the length and enter the dimensions into a list on the control. Normally, you don't have to setup on the table.

Others use a system like is explained here, but they have a subprogram which activates during a toolchange, the bit moves over to an out of the way place on the router bed, sets the height by the sensor and the coordinates are entered in the tool list automatically.

Trent

[ger21]

Our machine's Z zero is the bottom of the work piece, so when you home(ours has a reset button) the machine first time in the morning, it knows where Z-zero is. Like Trent says, all the tool lengths are stored in the machine and you don't have to do anything else all day. The part thickness (as well as width and length) are in the g-code file.


Julio, why not make your macro back up the 1", but set Z to +1, then you don't have to add 1" to all your cuts?

[JRoque]

Sorry about the link. Can you see if you right-click on it and "Save Target As..." works? You should end up with file zztouch.wmv which is a Micro$oft format movie.

If you change the tool in the spindle or the material on the table, you run the macro again. The length of the tool or how far sticks out of the spindle is irrelevant for this. The macro does this:

1. Moves Z down until it touches the sensor
2. Resets the Z DRO = 0.000, no movement
3. Adds height of sensor itself, 0.025" in my case
4. Resets DRO = 0.025" - no movement
5. Backs Z in exactly 1".

I'm hoping with this I won't have to worry about what chuck/tool/material I use. I will set my cuts to whatever depth I want to cut in, which will be a negative number. So even if I change the tool in the middle of the job, I can still be sure I will cut in exactly what I need.

Cheers,
Julio

[ger21]

Yes, the link works that way.

[jimbo]

nice machine, at least you can use this to make parts for the next one.

what are you using for the spindle?
edit: never mind. I reread the first post to see your spindle info.

[JRoque]

Yes, the idea is to build parts for itself for now.

The spindle is 1/2 HP and too fast for cutting aluminum - as I learned. I'll try attaching a couple of pics from the laser tachometer.

Yesterday I ordered a bunch of end mills from a place in CT. Very nice people and great prices. They're here: http://www.toolbuyers.com. After I cut a few parts and myself a couple of times, I'll concentrate on building a constant torque speed control for the spindle and see if I can make it run at 3 to 5,000 RPM with enough torque to cut Fortal aluminum.

L8er,
Julio

[InventIt]

For a "Contraption" it looks pretty good! I like your "air cleaner" is that stock?