View Full Version : RCAD by me

Robin Hewitt
26-10-2011, 08:45 PM
Not commercially available but after typing in nearly 4000 lines of C# I thought I might crow a bit :beer:

My program theme is "Instant gratification" on a flat learning curve. I do all the hard work in the AutoCAD drawing. By keeping it simple, someone else can open my .dxf file and cuts appear on the screen in the blink of the eye. There in no G-Code or any other kind of confusing code, it identifies and talks to either of my mills directly.

I use a .txt file to define the various machine and tool settings. See the pic. If I tell it "Cut outlines" it doesn't cut pockets. If I tell it "finish blue pockets" it will only trim pockets drawn in blue. The ultra simple tool path algorythm is not fast but it seems robust and caters for any dxf/txt file combination.

Best of all, I can use a USB2.0->Serial adaptor on a Windows 7 laptop. No more antique computers with paralel ports left in a cold dusty workshop for me. 'tis a liberation :dance:

blackburn mark
26-10-2011, 10:35 PM
Not commercially available

why ? .... is it machine specific ?
i dont understand the catch, maybe im reading it wrong but you seem to have circumvented a couple of the major ball aches of diy cnc :eek: and its not commercially available ? are you looking at developing it ?

Robin Hewitt
27-10-2011, 12:00 AM
are you looking at developing it ?

Hi Mark

An excuse to gloat a bit more :naughty: Thanks :smile: I wasn't actually expecting any replies :whistling:

I spent a lot of time and money looking for CNC software that was right for me. I couldn't find it so I wrote my own. The chances of this being right for anyone else seems somehow remote.

The AutoCAD end is easy if you know AutoCAD. But who uses AutoCAD these days? I am a bit of a dinosaur. I use a cheap AutoCAD clone called ProgeCAD which has the required AutoCAD structure to make a pukka dxf output.

Here's a pic of the drawing that created the cut file shown above...

Draw each cut level with lines, arcs and circles. Bulges have a positive thickness, pockets have a negative thickness. Bulges inside pockets not a problem, nest as many as you like.

It stitches everything together for you, I've never understood why some software makes you do that manually, it is so easy.

Anything with a zero thickness draws on screen but doesn't cut.

Zero thickness circles create location points, handy for drilling holes on a mill drill.

If you want a block outline to control waste removal you stick it on a seperate layer called "Block". If you don't draw a block it creates one that is a snug fit to the lowest outline.

I wanted it to cut injection tooling so f you put things on a layer called "draft_2.0" you impose a 2 degree draft angle on it.

Rounded sides similarly. It compensate for a ball nose cutter, "Tool 1.5 ball", but that really slows it down because the Z advances to keep the tool overlap constant on the arc circumference. Surface finish is paramount.

I do plan to allow blocks so I can tell it, "Cut fred" and it will go looking for blocks called fred.



blackburn mark
27-10-2011, 01:16 AM
I spent a lot of time and money looking for CNC software that was right for me. I couldn't find it so I wrote my own.

smart arse :smile: ... makes me feel a little less than clever

But who uses AutoCAD these days?

iv pretty much got my work flow squared away now but im pretty sure in the early stages of trying to crack the CAD to CAM issue i would have twisted your arm for a beta of your RCNC and id have learned AutoCad/ProgeCAD and given the thing a go given how simple you make it sound to use and how expensive and complex software can get

if your making molds with it its obvously working well

im gessing that drawing paths for thread milling might be tedious and the lack of a 4th axis would put some off but im kind of hoping somone who is just starting out and isnt after those functions WILL twist your arm and give it a go

nice one robin xxx
fingers crossed and good luck with it :)

Web Goblin
27-10-2011, 08:05 AM
I still use Autocad. I like it. Its the only thing I use for any 2D work to get cut on plasma or laser machines.


27-10-2011, 09:03 AM
I still use Autocad. I like it. Its the only thing I use for any 2D work to get cut on plasma or laser machines.

I used Autocad for 2D work until my old 2000 copy stopped working in Virtualbox on Linux. Tried ProgeCAD and couldn't get on with it. Now use DraftSight which is just like 2D autocad.

As for RCAD it sounds great. Much CAM software is just too complicated for us amateurs!


P.S. Is the sea in Seaford still as cold and rough as I remember it?

Robin Hewitt
28-10-2011, 10:07 AM
Is the sea in Seaford still as cold and rough as I remember it?

Hi Russell

I've lived by the sea for so long I only look at it if it is doing something truly spectacular.

I don't know if Rcad is user friendly because it really depends on me to get the drawing right. One outline that doesn't connect end to end to end +- 0.002mm will get you a terse response with only the XY co-ordinate as a hint.

You also need the USB to mill adaptor and the pendant to make it cut.

OTOH, it might be fun to find out. I'll put something together this weekend. You can unzip it into directory c:\rcad then feed it some dxf's and tell me if it is friendly or downright hostile :naughty:



28-10-2011, 01:47 PM
Looks like a nifty program Robin, good luck with it

Robin Hewitt
29-10-2011, 05:49 PM
Me again

I think you can probably try my program without installing anything that needs to be uninstalled if we are picky about where the files go. If this bitches about missing dll's etc., tell me so I can add them....

Find a 64 bit machine running XP or later.

Make a new folder c:\robin it will look there for all it's bits and pieces

Copy these files to c:\robin http://www.robinhewitt.net/robin.zip

Run rcad.exe

I have included a couple of .dxf's and some .txt files

al1.txt is a 1.5mm tool
al3.txt is a 3mm tool

To get rid of it, delete the directory.

I use the paid for version of AVG and it says I am clean.

If you do try it, let me know if it works :tup:



blackburn mark
30-10-2011, 10:41 AM
You also need the USB to mill adaptor and the pendant to make it cut.

whats this ? i couldnt find anything on google

Robin Hewitt
30-10-2011, 12:03 PM
whats this ? i couldnt find anything on google

Did you try it? I didn't think anyone would bother :heehee:

I've found a couple of bugs since posting...

1: If I open the gc.dxf with the al8.txt cut it chops the blooming thing in half :naughty:

2: Windows XP doesn't take you back to c:\robin when you change files like Windows 7 does :rolleyes:

I'm on it.

I only have the pendant in prototype right now. It has to be ultra simple to keep with the program 'zero learning curve' philosophy.

When cutting Red pauses it, Green un-pauses it.

When tool setting the XYZ Up Down buttons come into play. Green speeds it up, Red slows it down. The selected jog speed shows large on the screen because my eyesight is fading. It does 0.1, 1, 5 and 10 mm/s.

For large moves you use the PC mouse. Left button the drawing and it moves there in XY. Right button the drawing and it asks before relocating the tool to that position in XY.

For precise locations points you add circles to your drawing which show as red boxes on screen. Picking a red box picks the centre of the circle that created it.

To set Z you get 2 buttons on screen. "Set Z" asks before relocating Z to the highest object in the drawing. "Lift" moves the tool vertically to 10mm above that. If 10mm is wrong, you can change it in the .txt file.

I like my .txt files, they make it so simple to change the cut. Press "TXT File", right button the file then pick "Edit".

If anyone has ideas to make this simpler I am open to suggestions.



blackburn mark
30-10-2011, 01:18 PM
Did you try it? I didn't think anyone would bother :heehee:
strange boy !

iv downloaded it but my win7 64bit sytem is at home (im out at the mo)
it might not be usfull to me but im intruiged and i cant help thinking you might be onto somthing exciting

maybe if you get it all squared away you could make it pay by selling the pendants

Robin Hewitt
30-10-2011, 01:48 PM
I just fixed the extra cut bug. A tiny trig rounding error meant an intersection at the end of an arc could be missed. Told it to accept plus minus 0.0001 radians and the extra cut evaporated like morning mist. Uploading a new zip is a pain, I'll wait 'til I find a really good un'. :naughty: