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Gasgasbones
28-12-2014, 12:06 PM
Hi guys

Couple off questions if I may, I hope this is the right section for this.

I've engraved the steel buckle as shown from the DXF of the logo but the curves are not true curves but made up from smaller straight lines. The DXF is curved so unsure what's going on here ?

I'm presuming at larger scale it would be ok ?

I know the engraving is a bit of a mess, partly because of the size ( it's in a tight spot ) but I also need to use a smaller cutter tip and shallower depth. I'm happy sorting that out but is there anything that can be done about the angular curves or at this scale
am I fighting a losing battle?

To the naked eye it actually looks acceptable but a closer look it starts to look nasty !!

The DXF is made from an on old auto cad 2000 file, I'm running a boxford vmc190 with boxford software if that helps !
A friend did the original drawing for me years ago and I have little clue on what to do to fix!

Cheers guys

Carl

http://i956.photobucket.com/albums/ae44/ggbones/107f5fd76ef8a4729929cfac30ae2b9e.jpg

http://i956.photobucket.com/albums/ae44/ggbones/7521fe67f60791e1878238e9d93ceb62.jpg

cropwell
28-12-2014, 12:17 PM
Hi Carl,
How do you get from DXF to Gcode ? It would also be good if you could post your Gcode file to see what is generated to cut those arcs. I presume you are running Mach3, but to help you we would need to know the chain of software from DXF.

Gasgasbones
28-12-2014, 12:34 PM
I popped the file into draft sight and saved it as a DXF from a DWG.
I didn't do anything to it though. I really haven't got a clue with regards to programming etc and am just winging it at the mo with what I have got ! :-)

I have the program R unning now on larger scale and it's still angular curves so I'm presuming it's the G codes need sorting ?

how would I save a Gcode ?

Im running the boxford software that they issue now with no Mach 3 involved.

carl

Gasgasbones
28-12-2014, 12:50 PM
Trying to attach DXF, i think it worked ?

EddyCurrent
28-12-2014, 03:15 PM
It doesn't look like a dxf file to me

Gasgasbones
28-12-2014, 03:23 PM
Im lost Eddie.

Trying to generate a Gcode in Cambam. I thought I had sussed it but it wont save to DFX only as .CB and my boxford wont recognise the file !

cropwell
28-12-2014, 03:24 PM
Sorry Carl,

But I can't open the DXF file. I don't know the boxford software, so someone else would have to contribute towards a solution.

You are seeing the arcs as a series of straight lines because somewhere in the chain of events from drawing to machine movements, the code to move the miller has been reduced to a low resolution.

Does the boxford software take in the dxf file ?

It is frustrating but I have to pass on this one.

Rob.

Web Goblin
28-12-2014, 03:32 PM
I cant open that one in autocad either.
Sometimes long curves get broken up into smaller lines or if they are splines or so and they don't come out right when saved as a dxf I think.
Try loading the file back into cad then save it as a R12 or older version. Then reload it and save as a newer version dxf and try it again.

Gasgasbones
28-12-2014, 03:39 PM
I think ive sussed it fellas :-)

I managed to generate a tool path using the cambam and have exported to DXF. Im running it now but the curves look a lot curvier than before so far :-)

EddyCurrent
28-12-2014, 04:45 PM
I was just going to say, in CamBam you have to use; File --> Export --> to DXF

Gasgasbones
28-12-2014, 04:50 PM
Its just finished its program. still looks wrong :confusion:

EddyCurrent
28-12-2014, 06:39 PM
You still didn't post the dxf file

Gasgasbones
28-12-2014, 06:42 PM
has this worked Eddy ?

This is the one tried to smooth out on Cam Bam

http://i956.photobucket.com/albums/ae44/ggbones/mycnc.jpg (http://s956.photobucket.com/user/ggbones/media/mycnc.jpg.html)

EddyCurrent
28-12-2014, 07:10 PM
Yes that file loaded okay

Gasgasbones
28-12-2014, 07:14 PM
Is there any clue why it's doing the angular curves ?

EddyCurrent
28-12-2014, 07:30 PM
There were some lines that would not join, I've fixed them in the attached file, but it should not have caused your issues.
This what it looks like in the CutViewerMill simulator
14213

Are you using 'constant velocity' mode or 'exact stop' ?

Gasgasbones
28-12-2014, 07:38 PM
Cheers Eddy,

im afraid I don't know about constant velocity or exact stop ?

ill draw something curved on the boxford software tomorrow and try it but it's been doing other curves fine before, just this one I think has been a bit odd .

EddyCurrent
28-12-2014, 07:51 PM
Maybe try it again with the file I just sent, but the toolpaths in your picture look okay so will probably not help.
In CamBam have a look in the Engrave MOP settings, you will see one called 'Velocity Mode'

Gasgasbones
29-12-2014, 08:56 AM
Maybe try it again with the file I just sent, but the toolpaths in your picture look okay so will probably not help.
In CamBam have a look in the Engrave MOP settings, you will see one called 'Velocity Mode'


Hi Eddie

Just the same mate :-(

When the Boxford software draws the image before cutting its fine, just like yours. just when it cuts its all angular.

What do I do with velocity mode ? Im new to Cambam and cnc in general so im struggling here.
How can I re-draw it? I can over draw in draft site I believe but I dont know what tools etc to use on the software

Ta

Carl

EddyCurrent
29-12-2014, 02:59 PM
Hi Eddie
What do I do with velocity mode ? Im new to Cambam and cnc in general so im struggling here.
Carl

Try both options but make sure your machine is using the same option (if you can change it that is ?)
Have you tried any other CAM software to eliminate that ? although CamBam is a good one.