[wedge]

Hey, I am waiting on some plans to build a cnc hobby mill, and wondering when I design a part in CAD, then convert it to G-Code, after that do I just stick it in the CNC control program and tell it to cut, or is ther anything that has to be added into the G-Code to make it cut out the part correctly????

Thanks allot

Will

[Rekd]

It will depend on your post and the complexity of the part. Generally, I don't make edits, but many peeps do.

'Rekd

[Mr.Chips]

Welcome

Here's a link that will anser some of your questions:
http://www.cuttingedgecnc.com/makingpart.htm

Check out the rest of the site lots of good information.

Good luck.
Hager

[Rekd]

Hager, that's a pretty old link isn't it?

Step 3- Offset the Part


The milling machine does not know what size cutter your using until you tell it. It will "trace" the CAD lines and the toolpath must be offset 1/2 of the cutter diameter. You will need to figure out if your converting program will do this for you. If not, which way will the offset be placed so the finished part comes out correct. Notice in the picture, I moved the "offset" path to 0,0 (origin) so I know where to line up the machine for the part later. Also note one of the toolpaths is not offset.

I haven't seen a program in eons that doesn't do this almost automatically.

'Rekd

[Mr.Chips]

I'm still building, hung up on a part to my Z axis.

I saw this and thought there was a lot of good information. Sorry if it's out dated.

I plan on using TurboCNC to start, hope it has all of this.
Hager

[Rekd]

Just because it's outdated doesn't mean it's useless. There's good info there that still applies. I just thought it was funny about offsetting geometry to the tool's radius.

'Rekd

[dherbman]

I once replaced a programmer I was contracted to train at a board shop. He had no CAD tho and was trigging everything out to create the GCODE. He was actually calculating the cutter path. No software used, all input into the controller one charcter at a time.

Worst part was when I introduced him to G41/G42 and cutter comp tables, he defended his method as being superior because he knew exactly what he'd get. It took all his 1/8" bits away and asked how he'd get the job out with 1/16" bits. "Reprogram" was his reply. That was enough for me. I can tolerate ignorance, but stupidity is too much for me to handle.

Originally posted by Rekd
Just because it's outdated doesn't mean it's useless. There's good info there that still applies. I just thought it was funny about offsetting geometry to the tool's radius.

'Rekd

[buscht]

Rekd, As far as I know you have to offset the geometry when you use TurboCNC because it doesn't have cutter comp available, just tool length offsets.

So the information on the website would be valid.
T

[Rekd]

Originally posted by buscht
Rekd, As far as I know you have to offset the geometry when you use TurboCNC because it doesn't have cutter comp available, just tool length offsets.

So the information on the website would be valid.
T

Note to self: don't EVER take a job that uses TurrboCNC!

'Rekd