Export dxf for cnc tube bender

Hello, I have a problem with exporting dxf files to our tube bender. We make stainless steel frames for boat covers and want to program our tube bender with a dxf file that should translate automatically into a bending program in the bending machine software. The problem we have is that it doesn’t translate correct at all. What I have done (or at least what I think I have done, I’m fairly new to cad and rhino) is the following process:

  • digitized frame curve with a proliner 8 digitizer
  • export dxf to rhino (export as polylines, but can be lines & arcs)
  • cleaned up lines, made frame line symmetrical
  • exploded frame line
  • converted curves to arcs (straight segment should be converted to lines)
  • exported to dxf
    Here I have tried many different settings in the dxf export options, R12 lines & arcs is the one I have been recommended to use and tried unsuccessfully.

The problem I see in our bending machine is that the software mixes up the order in which the lines and arcs are supposed to be in and also the radiuses becomes a negative value when it shoud be a positive.

The tube bending company has not worked in rhino and has given us not so good info on what the file should be like except that it should be build up step by step and not be a polyline.

Attaching exported dxf and image of export parameters.

Thankful for any advice / Isak

1011h_angle2_explode_poly.dxf (8.3 KB)

So…it sounds like the result should be like a sequence of operations like a GCode file? But a DXF? I don’t know what you’re supposed to do about that. Does the bender not have software to take what you give them and output what they need? Seems like they’re being obtuse, metal fabrication is a bit of a black art and the way I’ve always worked with that stuff is just to show the result required, I can’t imagine ME creating a file that’s fed directly into a bender and it coming out correctly first time.

The bender has an dxf import function into its software but it’s not very well described in the manual, more than it’s there.

This is what it looks like when imported (not the file attached in the first post but similar problem)

This is what it should look like (reprogrammed manually in the bending software)

Bevor export try command _Join and _Convert and read output from command _What

Output=Arcs SimplifyInput=No DeleteInput=Yes AngleTolerance=2 Tolerance=0.01 MinLength=0 MaxLength=0 OutputLayer=Current

No idea if change this would helps

This seems to work better, thank you very much.
Joining before converting helped and also ticked the flip arc normals. Exploded the resulting curve after exporting

@isak1 I am always on the lookout for CNC tube bending vndors. Where are you bending the tubes?

@koramblyum we’re located in the south of Sweden, but we’re not a vendor of tube benders, we are a boat cover company.