7 Replies Latest reply on Oct 26, 2014 5:06 AM by Paul Cullen

    Adjusting sketch lines for Lasercutting

    Mitchell Faas

      Hi,

       

      I am currently working on a project that would require over 0.1 mm of precision in the cuts made, to this end I decided to go with laser cutting but to get my files ready I need to prepare the drawings for the laser. Meaning that I have to take the laser width of 0.2 mm in to a count (0.1 mm on either side of the line). Can someone here inform me about how to export this in your drawing?

       

      Thanks in advance.

        • Re: Adjusting sketch lines for Lasercutting
          Fraser Port

          You shouldnt need to do anything. Draw it to the size you want and as long as the machine and its pre-processing software is capable of the 0.1mm you require, you'll be laughing.

            • Re: Adjusting sketch lines for Lasercutting
              Mitchell Faas

              The company itself told me that I should offset these lines so I doubt that that is the case.

                • Re: Adjusting sketch lines for Lasercutting
                  Fraser Port

                  I'd be interested to know why they have requested this as far as I know all machines have a kerf width from waterjet being narrow to oxy fuel for heavy plate at the wide end of the scale.

                  Ive never had to adjust to suit a machine ever. I hope I dont have to ever start adding allowances.

                   

                  Cheers, Fraser

                  • Re: Adjusting sketch lines for Lasercutting
                    Paul Cullen

                    Hi Mitchell

                     

                    As Fraser has said you should not have to compensate for the width of the cut on the machine. The software that runs the machine should do this. I have been using plasma / laser / water jet etc. for over 20 years now and the machine software always took care of this, as the kerf (width of cut) could vary depending on what thickness of material and settings your are using and that's just using the same machine to cut different materials. On a plasma machine cutting 4mm plate it might have an offset setting of 0.2mm but cutting 15mm it might have an offset of 0.4mm the machine software always takes care of this.

                     

                    I think you should find a different company to cut your parts. If they are asking you to put the offset into the dwg / dxf file that you are going to send to them, then either they don't know what they are at or they are trying to compensate for inaccuracies in their machine or settings. Either way it sounds very wrong.

                     

                    If you have to produce the offset it might be easier to save the dwg / dxf as normal then open the file in draftsight and offset your part outline there.

                • Re: Adjusting sketch lines for Lasercutting
                  John Mullett

                  As others suggest the offset is handled by the laser controller based on the power output and purge gas used.  Unless you are talking about some kind of small scale scientific application making semi-conductors or optical diffraction gradient, 0.1mm precision is getting pretty tight within the  laser and waterjet metal fabricating discipline.  These guys use steel rules and calipers at best, and pin gages or micrometers would be unusual.

                   

                  I think your needs might be more in line with machining or better yet wire EDM if you are wanting metal cutting precision.   Wire EDM machines can cut in the 0.01 mm range all day  with little difficulty.

                   

                  We can provide pricing for your parts for any of the above processes directly from your tolerance Solidworks model.  No special drawings needed.

                    • Re: Adjusting sketch lines for Lasercutting
                      Mitchell Faas

                      I'm using wood, not metal.

                       

                      (Making a puzzle box)

                        • Re: Adjusting sketch lines for Lasercutting
                          Paul Cullen

                          Ok I guess they are telling you to offset by 0.1mm to allow for material shrinkage as it is wood you are working with.

                           

                          If you have your box modeled as an assembly with say 6 different parts for your sides. I would open each part and create a new configuration called laser, I would then start  a new sketch on the face of my part and offset all the outside edges by 0.1mm then extrude this sketch as a solid body and then export this to a dwg file.

                           

                          I still think that they should be able to do this in the software on the laser cutter. Say the width of the cut is 0.2mm and you want to make the part 0.1mm larger just tell the laser the cut width is 0.4mm and your parts will be 0.1mm larger