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So I have made the bed. I few minor G Code mistakes when doing the slots for the T tracks. That's the learning curve factor for me.

Overall, I'm very happy with this, still a few minor adjustments to fiddle with though. Still thinking about the ball type lead screw upgrade in the near future. Also still need to add my limit switches.

Mike

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I'm outside looking in, just farther from the window than most.

It’s way cool when the machine you are building helps in the process.

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Rich S

"The inconvenience of poor quality will linger long after the thrill of a bargain has been forgotten"

you are so right . It is so cool even with typos in the gcode to have the build progress the build for you.

Now I have to figure out the vacuum/dust collection. Anyone out there please post your solutions please.


Thanks

Mike

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I'm outside looking in, just farther from the window than most.

One more thing I know many here already know Gcode and this is basic. but for me and those just learning here is the code I wrote to level my bed. Remember to adjust for your bit diameter as I used a 1/2" and also for your actual cutting area. mine was x0 to 40" y0 to19.5"
mike

(TABLE LEVEL GCode) ( 1/2" STRAIGHT BIT)
(ADJUST Y and X axis to suit cut length and width of table)
( Z zero was set for 1inch above table bed before the cut)
( G Code, by MiKro 11/19/09 )

G0 X0 Y0 Z0.050
F30
G1 X0 Y0 Z-1.020
G1 X40
G1 Y0.250
G1 X0
G1 Y0.500
G1 X40
G1 Y0.750
G1 X0
G1 Y1.000
G1 X40
G1 Y1.250
G1 X0
G1 Y1.500
G1 X40
G1 Y1.750
G1 X0
G1 Y2.000
G1 X40
G1 Y2.250
G1 X0
G1 Y2.500
G1 X40
G1 Y2.750
G1 X0
G1 Y3.000
G1 X40
G1 Y3.250
G1 X0
G1 Y3.500
G1 X40
G1 Y3.750
G1 X0
G1 Y4.000
G1 X40
G1 Y4.250
G1 X0
G1 Y4.500
G1 X40
G1 Y4.750
G1 X0
G1 Y5.000
G1 X40
G1 Y5.250
G1 X0
G1 Y5.500
G1 X40
G1 Y5.750
G1 X0
G1 Y6.000
G1 X40
G1 Y6.250
G1 X0
G1 Y6.500
G1 X40
G1 Y6.750
G1 X0
G1 Y7.000
G1 X40
G1 Y7.500
G1 X0
G1 Y7.750
G1 X40
G1 Y8.000
G1 X0
G1 Y8.250
G1 X40
G1 Y8.500
G1 X0
G1 Y8.750
G1 X40
G1 Y9.000
G1 X0
G1 Y9.250
G1 X40
G1 Y9.500
G1 X0
G1 Y9.750
G1 X40
G1 Y10.000
G1 X0
G1 Y10.250
G1 X40
G1 Y10.500
G1 X0
G1 Y10.750
G1 X40
G1 Y11.000
G1 X0
G1 Y11.250
G1 X40
G1 Y11.500
G1 X0
G1 Y11.750
G1 X40
G1 Y12.000
G1 X0
G1 Y12.250
G1 X40
G1 Y12.500
G1 X0
G1 Y12.750
G1 X40
G1 Y13.000
G1 X0
G1 Y13.250
G1 X40
G1 Y13.500
G1 X0
G1 Y13.750
G1 X40
G1 Y14.000
G1 X0
G1 Y14.250
G1 X40
G1 Y14.500
G1 X0
G1 Y14.750
G1 X40
G1 Y15.000
G1 X0
G1 Y15.250
G1 X40
G1 Y15.500
G1 X0
G1 Y15.750
G1 X40
G1 Y16.000
G1 X0
G1 Y16.250
G1 X40
G1 Y16.500
G1 X0
G1 Y16.750
G1 X40
G1 Y17.000
G1 X0
G1 Y17.250
G1 X40
G1 Y17.500
G1 X0
G1 Y17.750
G1 X40
G1 Y18.000
G1 X0
G1 Y18.250
G1 X40
G1 Y18.500
G1 X0
G1 Y18.750
G1 X40
G1 Y19.000
G1 X0
G1 Y19.250
G1 X40
G1 Y19.500
G1 X0
G1 Z0

G0 X0 Y0 Z0
M30

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I'm outside looking in, just farther from the window than most.

SO I have upgraded to ballscrews. OMG what a difference. Night and day difference.

I do have some issues with mid range resonance that I must deal with but I think that it is manageable. if I can't isolate it, then I'll make some harmonic dampers. otherwise I gained 4 to 5 times in speed. The harmonics are in the 60, 120, 180 IPM range, think i see a pattern here

MK

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I'm outside looking in, just farther from the window than most.

Sounds like the steppers might be in cahoots with the fluorescent lights, Mike.

I had the same problem with such drives.
After trying LOTS of things, I finally installed Geckodrives (the red ones, can't remember the type of drive right now, I think they are called 203V or something) and the problem was solved. I guess they have some sort of resonance damping stuff inside or something... I could also double the speed at the same time, without stalling the motors (both the feedrate while cutting and offcourse also the rapid movements).

you might wanna give this a try (try one axis first)

Mike,

just for fun, here is an example of making your code a little bit shorter, by looping a subprogram inside your program.
This was sort of the way I wrote such G-code programs when I just got into CNC programming, before I learned to use CAMsoftware, writing scripts/macro's, parametric programming, making wizards, etc...

There are offcourse many more ways of doing this, it's just an example of how you can make it easier for yourself.

WARNING: I left out a lot of initial G-codes that I normally include at the start of a program (G17 G40 G80, etc...) + it might not work on every machine. some machines use other codes and parameters for the subprogram call and for indicating the loop value.
it should work in mach3.

for this example I used your dimensions and Z-values

(leveling surface)
G90 (set absolute)
G00 Z0.05
G00 X0Y0
G00 Z0.01 (rapid to just above material)
G01 Z-1.020 F30
G01 X40 F30
M98 P0001 L39 (loop subprogram 39 times)
G90 (set absolute again, just to be sure)
G00 Z0.05
G00 X0Y0
M30 (end program and rewind)

o001 (subprogram)
G91 (set incremental)
G01 Y0.250
G90 (set absolute)
G01 X0
G91 (set incremental)
G01 Y0.250
G90 (set absolute)
G01 X40
M99 (end subprogram)
%

Thanks,
yep I figured there was an easier way later down the road. By using incremental mode and loops as well

Gcode is a new thing for me so I am absorbing it as I go Each day learn something new and different ways of doing it. Sometimes they mix sometimes they don't.

Funny how it works, Someone in another thread was talking about and angled neck pocket and angling the body to the bed? Depending on where you put the Z command in a G1 with constant velocity will
++++++++++++++++++
G1 X2 Y2 Z0
Two different things going on from here depending on which set you use Ignore the (( ))
(((
G1 X0 Y0 Z-1
)))

)))))
G1 X0 Y0
G1 Z-1
(((((
++++++++++++++++++++++++++
determine if it plunges then moves x or y or slowly tapers to the new X or Y coordinates. Thus the angle? Very simple if you see it. I tried different things along the edge of a board just to see the diff in what the code does. Interesting when you see it happen vs what you think it will do?..

MK

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I'm outside looking in, just farther from the window than most.

sometimes programming is much faster with G-codes than with CAD/CAM, so it is indeed a good plan to learn g-code programming.

one more tip:
if you noticed I used G00 Z0 and then on the next line G00 X0Y0 at the end of the G-code I posted, instead of putting them on the same line like you did before (G00 X0 Y0 Z0)

unless you need the "3D motion", it is much safer to do your X0Y0 moves with Z all the way up (Z0 on my machine)

don't ask how I learned this

You only 'learned' it once? Lucky guy!

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

I agree, I still make that mistake and it's only been a month + now

It's, I get in a hurry and don't think.

Merry Christmas all.
Mike

_________________
I'm outside looking in, just farther from the window than most.

Another way to save some key strokes:
The G codes don't need to be repeated on every line, it keeps the last G01/G00 until it sees a different G code.

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Jim Watts
http://jameswattsguitars.com

Looks good Mike. Do you have an estimate of what it cost you to build this? I have a shop full of woodworking tools, no metal working tools. Did you need metal working tools (specialized)?

Mike

Around $1500, that included the PC. I spent more but they were my mistakes. So it can be done for around $1200. Thats without the PC. also does not include any software.

As far as tools, I used my Chop saw with a 60tooth finish blade in it from Homedepot. It costs about $20. Just have to take the cuts slow and steady. I did have access to a friends machine shop for some of the parts but most can be purchased already milled.

Things I have learned from this build are. Use ball screws, not lead screws. Use good quality couplers between motor and screw shafts. I have been fighting mid band resonance issues that have not allowed me the IPM I would like. My rapids are 100 IPM anything over and I get a stall from the resonance. I did a test today and made some couplers out of UHMW and low and behold the Resonance issue is gone. I can get 300IPM no problem. Now these won't last long, so I'll order some Buna N style couplers as soon as I can find some. Probotix had some on Monday, now they are sold out. I knew I should have ordered them

Have A Merry Christmas Everyone

Mike

_________________
I'm outside looking in, just farther from the window than most.