cnc newby

[buggman]

Hi mine name is bugsy from indian river, Ontario just east of Peterborough. New to the cnc would appreciate any help any one has to offer.
Thanks

[robertspark]

welcome

the technical tips section is a good place to start out understanding plasma CNC and what can make a good setup.

also this webpage which was done a short while ago is very informative
http://linuxcnc.org/docs/devel/html/pla ... rimer.html

[Rodw]

also this webpage which was done a short while ago is very informative
http://linuxcnc.org/docs/devel/html/pla ... rimer.html

Robert thanks for the endorsement of the article I wrote. There was input from a lot of others. Hopefully it might help some newbies avoid some of the things I learnt the really hard way.

[acourtjester]

one simple way to look at CNC is it is like GPS, movements are to move to new location from the current location. These movements have the information as to distance and direction built in.
Nearly all CNC machine uses a Cartesian coordinate system based on an X, Y, and Z axis

axis direction.jpg (21.1 KiB) Viewed 474 times

axis corrdinate.jpg (23.54 KiB) Viewed 474 times

[robertspark]

also this webpage which was done a short while ago is very informative
http://linuxcnc.org/docs/devel/html/pla ... rimer.html

Robert thanks for the endorsement of the article I wrote. There was input from a lot of others. Hopefully it might help some newbies avoid some of the things I learnt the really hard way.

Rod,

It is a very good article that has substance and not just waffle, you back it up with numbers such as the torch height voltage and many other bits. and can be read by anyone who would gain something from it in some way and it also acts as an aide memoir for some of us that (I've genuinely forgot the word!!!) short term memory loss seems to be creeping in....

I try to always link it to new users who state they are starting out as if they read it a few times you wouldn't get half the basic questions that sometimes popup on the various cnc forums (cnczone + plasmaspider + uccncforum + mach forum)..... just people sometimes don't want to read

[Rodw]

It is a very good article that has substance and not just waffle, you back it up with numbers such as the torch height voltage and many other bits. and can be read by anyone who would gain something from it in some way and it also acts as an aide memoir for some of us that (I've genuinely forgot the word!!!) short term memory loss seems to be creeping in....

I try to always link it to new users who state they are starting out as if they read it a few times you wouldn't get half the basic questions that sometimes popup on the various cnc forums (cnczone + plasmaspider + uccncforum + mach forum)..... just people sometimes don't want to read

Yes I know the feeling. You actually prompted me to read it again. There is some additional content I could add to include the more sophisticated model of ohmic sensing developed in conjunction with Mesa. Now I'm wondering if there should not be a section about XYZ coordinates.

The diagram of a gantry machine posted here earlier in this thread seems wrong to me. A machine builder can choose any of the four corners of his machine to be X,Y origin but the positive directions follow the conventions we learnt in school about cartesian geometry except we are only interested in the top right quadrant where both X & Y are positive. This then places the origin at the front left of the machine when viewed at the front. What is the front? Well that is your choice but when you stand facing the machine on that side, the origin is the corner on the side closest to you on the left. The diagram is placing the origin on the right.

I did try an alternative corner, but I found that the least confusing layout was to make the X axis be the axis along the gantry and the Y be the "joint" axis that carries the gantry assembly up and down the bed. That way, the front of the machine is when you stand with the gantry rail parallel to your chest and the positive Y direction moves the gantry assembly away from you. ie. in that diagram, I would swap the X and Y axes.

It was really misinformation like this that I was trying to demystify and shield the new user from. Perhaps its becasue the image has been used out of context from its original intended use.

[Rodw]

This is my preferred layout. with the front being at the dotted line for the X axis

[buggman]

hey I am looking for cut ready dxf files I am getting frustrated just wood like to see and cut a design thanks for the welcome

[acourtjester]

Buggman are you looking for a cut ready file for cutting metal or wood/plastic. The reason I ask is for plasma cutting metal you ID the surface and operate above that surface. I you are cutting wood/plastic/aluminum after you ID the surface you operate below that position. The DFX file is the same and the planning function you select a tools and the Post Processor and this creates the G-code which operate the correct functions on the CNC table.
Also give some size considerations in the file you would like.