[Treeman77]

Hello can someone please assist me? When I upload my dxf files they are missing sized (to large or of of working area) when I upload them I'm using planet cnc software I just need to learn how to put the files into the correct size and into the modeling area so I can machine them properly.
Many thanks and greatly appreciated some advice!

[joeavaerage]

Hi,
.dxf files are drawing files, not Gcode. CNCsoftware controllers like PlanetCNC use Gcode to describe machine motion.. You need a program that can convert a drawing (dxf) into Gcode.
Such programs are called CAM, Computer Aided Manufacture. The oldest and probably still the best is MasterCAM. If you have to ask how much it is then forget it......it costs a bloody
fortune.

I use Fusion. I pay a yearly subscription because I like it and want to access all its features, but Fusion is free to hobbyists and startups. I believe it has the capacity to import dxf
files and thereafter produce Gcode.

Craig

[Treeman77]

I use Fusion 360 and can upload the dxf into the cnc software to read g-code fine my problem is when I upload my dxf file into the cnc software my project is too large and I'm not sure how to adjust it from that point in the system. Thank you for your help!

- - - Updated - - -

I use Fusion 360 and can upload the dxf into the cnc software to read g-code fine my problem is when I upload my dxf file into the cnc software my project is too large and I'm not sure how to adjust it from that point in the system. Thank you for your help!

- - - Updated - - -

I use Fusion 360 and can upload the dxf into the cnc software to read g-code fine my problem is when I upload my dxf file into the cnc software my project is too large and I'm not sure how to adjust it from that point in the system. Thank you for your help!

[peteeng]

Hi Treeman - What do you mean by "its too large" haven't seen that issue before... Send the error code and example to fusion support. They have answered my questions very quickly... Peter

[Superman]

Hello can someone please assist me? When I upload my dxf files they are missing sized (to large or of of working area) when I upload them I'm using planet cnc software I just need to learn how to put the files into the correct size and into the modeling area so I can machine them properly.
Many thanks and greatly appreciated some advice!

I think Craig thinks you are "driving" your machine from the DXF file...
DXFs are created in position & size with the originating CADware.
It is in your software that you need to adjust the design. To resize. Look for "scale" where 100% is current size (some CAD may use 1 as current size). Usually it scales around the screen origin point (you might be able to select a different focus point).
After scaling, you then "translate" (move it, mirror, rotate etc) into a zone suitable for programming your toolpaths. Your stock size is created relative to your origin, & your design is placed within this stock.

[Treeman77]

Thank you I'll check this out and work on it I'm new to cnc I appreciate your help!

[michalsok]

You may also be dealing with improper units.
I ran into that before.
If the drawing is in mm but in the import screen you tell it that units are inches, it will import 25.4 times larger and appear huge in the working area.
Just a thought.

[PlanetCNC]

DXF files are "unitless". They do not contain any units.
When importing user must choose Metric or Imperial units and correct Scale factor

[Superman]

DXF files are "unitless". They do not contain any units.
When importing user must choose Metric or Imperial units and correct Scale factor

Nah.... I dont believe this. It does know what units the DXF was created in.
If I do a CAD drawing of a 1" cube, export a DXF
Now open that DXF into a different CAD system (default is millimetres) it will be a 25.4mm cube... not a 1mm cube

[PlanetCNC]

If you don't believe that doesn't make it true. DXF is unitless and that is a fact.

[RaderSidetrack]

I thought I would provide a link to an independent 3rd party to weigh in on this.

Imported DXF or DWG file in Fusion is not correctly scaled

Autodesk Support

Jan 12, 2024

---

Products and versions covered

---

Issue:

The scale of a DXF or DWG file imported into Fusion is incorrect.
Causes:

• A DXF file is a unitless file type so when Fusion reads the file, by default. It will assume that the file is in centimeters unless otherwise specified during insertion.
• A DWG file is exported with unit-less settings in the units in AutoCAD

Link: https://www.autodesk.com/support/tec...ect-scale.html

Autodesk is the publisher of a variety of popular products, including Fusion and AutoCad.

[Superman]

I thought I would provide a link to an independent 3rd party to weigh in on this.



Autodesk is the publisher of a variety of popular products, including Fusion and AutoCad.

Ok ... can you guys explain this link
https://ezdxf.readthedocs.io/en/stable/concepts/units.html
This was seen in various docs explaining units, so I am assuming a generalised example.

Yes... the header area is unitless, but the dimension area HAS units
It sets the modelspace layout to the setting in $INSUNITS, then creates the objects to to those units (or scales it to match the import target layout).

It has to know what units the screen objects are before importing & displaying.

[PlanetCNC]

...can you guys explain this link...

The DXF reference has no explicit information how to handle units ...

Some programs use $INSUNITS property (like BricsCAD) for units but this property is actually used for something else.
https://help.autodesk.com/view/ACD/2...A-EEF55A2B4FD8

In the last 30 years I opened and examined thousands of dx files. Most of them don't even have INSUNITS property. That is why an option to select units and scale is there.

[PlanetCNC]

But perhaps more programs now use INSUNITS property.
I'll implement automatic unit detection based on this property. It is trivial task.
This is what I'll do.

        switch (dxf.Var_INSUNITS)
        {
            case 0: { break; } // Unitless
            case 1: // Inches 
            {
                _Param->DataUnits = Units::Inches;
                _Param->Scale = 1;
                break;
            }
            case 2: // Feet
            {
                _Param->DataUnits = Units::Inches;
                _Param->Scale = 12;
                break;
            }
            case 3: // Miles
            {
                _Param->DataUnits = Units::Inches;
                _Param->Scale = 63360;
                break;
            }
            case 4: // Millimeters
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 1;
                break;
            }
            case 5: // Centimeters
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 100;
                break;
            }
            case 6: // Meters
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 1000;
                break;
            }
            case 7: // Kilometers
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 1000000;
                break;
            }
            case 8:// Microinches
            {
                _Param->DataUnits = Units::Inches;
                _Param->Scale = 0.000001;
                break;
            }
            case 9: // Mils
            {
                _Param->DataUnits = Units::Inches;
                _Param->Scale = 0.001;
                break;
            }
            case 10: // Yards
            {
                _Param->DataUnits = Units::Inches;
                _Param->Scale = 36;
                break;
            }
            case 11: // Angstroms
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 0.0000001;
                break;
            }
            case 12: // Nanometers
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 0.000001;
                break;
            }
            case 13:  // Microns
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 0.001;
                break;
            }
            case 14: // Decimeters
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 100;
                break;
            }
            case 15: // Decameters
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 10000;
                break;
            }
            case 16: // Hectometers
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 100000;
                break;
            }
            case 17:// Gigameters
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 1000000000000;
                break;
            }
            case 18: // Astronomical units
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 1.496e+14;
                break;
            }
            case 19: // Light years
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 9.461e+18;
                break;
            }
            case 20: // Parsecs
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 3.086e+19;
                break;
            }
            case 21: // US Survey Feet
            {
                _Param->DataUnits = Units::Millimeters;
                _Param->Scale = 1200000 / 3937;
                break;
            }
            default:
                break;
        }