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ptjw7uk
11-06-2009, 03:41 PM
Hi,
As my conversion gets nearer to being usable I now realise I have no idea of how to go from a drawing to g-code to input to the controller.
The controller I have is the cnc2 by conquerer design and uses their easycnc2. The software can to engraving directly but has very limited drawing facilities their newer version can inport dxf drawings etc but that costs more and as I have so much invested I would like to actually machine something rather than spend even more cash.
So how does one produce useful code of the g-code variety or does one do it by hand as you could with the old HPgl code.

Also can g-code be looped or does it have to be line after line of code!

Peter

Robin Hewitt
11-06-2009, 07:13 PM
There is way too much software out there to do this, and even more opinions about which is best.

What kind of shapes are you wanting to cut?

Can you stand a learning curve or do you want it easy?

ptjw7uk
11-06-2009, 07:26 PM
I'm not really sure waht shapes I want to cut but would like to cut parts for model boats or a model cannon that I have been making for years.
Its just at the moment I do not see how to get from a drawing or scanned image to the gcode.

Peter

BillTodd
11-06-2009, 07:41 PM
ts just at the moment I do not see how to get from a drawing or scanned image to the gcode.
Have a look at SheetCam (http://www.sheetcam.com/) It's a simple 2d program that'll take a .dxf file and allow you to choose what to do with various parts (i.e. pocketing, drilling profiling etc.etc.)

John S
11-06-2009, 10:42 PM
Peter,
A lot depends on what your controller expects. I downloaded the demo of easycnc2 and to be honest I wasn't very impressed. There are three types of people putting these packages together, Techies, Graphics Artists and machinists.........it wasn't the latter.

http://www.stevenson-engineers.co.uk/files/easycnc2.jpg

17 million fonts in windows and some twonk has to get all artistic ? A machinist wants something that can be read 4 shops away.
First screen has an instruction at the bottom that says click on file and select new, we have Edit, Machine, Emulate, Settings and Help.

No file, file should be next to Edit, [ standard windows layout ] aahh wait click green icon of a milling machine and you get file.

Silly me why didn't I think that one green icon and 5 standard windows tabs are normal ?

Anyway to get back to your question how to get G Code.

There are three stages in getting code, one you draw your part in CAD, plenty of free or cheap cad programs out there, been covered many times, go a google.

Second is getting a drawing file to code and this entails using a CAM package. Again plenty out here from simple to mega complex and expensive.
Unfortunately not many free ones and not many good cheap ones.
Kip mentioned using Lazycam that is built into Mach, it's one of those programs that either [a] you can use it straight off or [b] you never get the hang of it, the free one is limited, pro version is a paid upgrade.
Sheetcam is good, Vectric 2D is good, both have a similar price tag and from there on it's chequebook out time.

However [ big drum roll ] there is a simple free way with no strings attached.
Go to http://www.flashcutcnc.com and look at there controller.
It's a stand alone controller that used the usb port and outputs to a set of drivers.
It also has a $1,000 price tag.

However the software on the site isn't crippled as you need the USB box to make it run.
Download the demo version, not live version and under File [ which is in the correct place :whistle: ] select import DXF and find your DXF, note here the drawing will have to be drawn offset as the program can't work out offsets.

Load the dxf and the first thing it wants to do is save it as drawingxxx.fgc in C:\FlashcutData|DXF, let it do this.
then you get a menu box up where you put depths, cutc per pass, feeds etc and press OK and it writes the code and you can see it run on screen but you can't cut it as you don't have the USB Box.

BUT the code is now residing in C:\Flashcutdata|DXF\drawingxxx.fgc
Open this in notepad and you now have a valid G Code to use in your controller of choice.

.

ptjw7uk
12-06-2009, 09:50 AM
Thank you John, a very clear decription of what I need to know. I looked at the new version of easycnc3 but could not decide if the extra £100 was worth the expense. So I will try the route that you have outlined and see where it gets me. My conversion of my x1 is almost running but I have now getting problems with the connector nut on the ballscrew coming undone. I have made a couple of locknuts and now have to disassemble tofit them. Main problem with the nuts is the thread is not normal m8 x 0.75 so I have had to make my own lock nuts.

Another thing that is worrying me is how to lubricate the ways, either oil or grease vis oilers or nipple, I think I must have spent more that buying a ready made kx1 by now.

peter

ptjw7uk
20-06-2009, 08:48 AM
Just had a quick play with the free version on Cambam, seems to be easy to use and imports dxf files so I may go this route.

Peter

John S
20-06-2009, 10:51 AM
Strange thing with Cambum is you get charged to be a beta tester....not even RC yet.

Free version is free but it's dated and won't move in time.
Pro version is actually a release version, works for many.
It's just Andy's way of saying he's still working on it but without an income it can't move forward.

At least he's honest about the program unlike many of the snake salesmen out there who promise you anything just to get the sale. I have had Turbocad from V3 onwards, every new version has promised a command line, still no command line in V16

If you have ever worked a CAD system with a command line you will never go back, virtually a full drawing screen, no stupid toolbars and icons you can't understand, no drop down boxes you have to type into and move to the next box etc.

Want to draw a 20mm circle ? type C,20 and place it where needed.
Keyway 8 x 45 along a shaft ? KY,8,45,0 and place it.

Anyway to get back to Cambam, it does work, it has a good following and a nice user base as regards support and it's enough to get you do do most things in a home shop until you need to move onwards if ever.
3D is nice but 90% of all manufactured parts are still done in 2 1/2D.

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John S
20-06-2009, 11:56 AM
Right then how to fix the cockup on my latest part................

Weld a lump on and machine 'nearly' all of it off again. :biggrin:

BillTodd
20-06-2009, 04:03 PM
I saw the strangest thing ever on Wednesday...Aluminium welded with steel.
!
My brother has a small sample of brass welded to aluminium (i.e. no glue). Apparently he got it from a firm specialising in 'explosive' welding ????

ptjw7uk
20-06-2009, 04:51 PM
Not new, some years ago there was interest in steel sheet with a copper (or may have been nickel)layer explosively weled for ships hulls not heard of it lately supposed to make the ships cheaper to run by reducing marine growths.

peter

John S
21-06-2009, 12:17 AM
I saw the strangest thing ever on Wednesday...Aluminium welded with steel....I'll take a photo of it for posterity....Incredible!



Do a search on Fluxless Laser Brazing, I think Corus may have the patent on it, remember reading something about it in one of the trade mags.

.

John S
21-06-2009, 12:49 AM
For a bet once I stick welded two pieces of 10 thou steel shim together. Perfect weld.

Good for a pint in the pub because no one will believe you but it's a doddle to do once you know the method.

No I'm not divulging for less than a pint, real not virtual.:yahoo:

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