Laser cutting with cam

[jcsantilli]

I'm a bit lost here in this department. I'm experimenting to use CAM to laser a wood part with a Universal laser.

I figured out how to choose the laser tool. Now the problem is, do I have to use the post processor? Universal is not in the list of machines. How do I do this?

There any tutorial specific to this.

Thanks

[djowen40 · Accepted solution]

Universal laser have provided a post specifically for this task. Download the post file and place it in your personal post directory and away you go. it will produce DXF files that can be imported into the laser system

https://cam.autodesk.com/hsmposts?p=universallaser

[jcsantilli]

Thank you Djowen,

I guess the next question is how to make a flat DXF. I'm making a box and of course the components are in differents planes. What would be the best way to create the DXF of each part and make a single file so I can laser the 6 sides at once?

Thanks

[michael55SE4]

In Fusion360 I usually start with a single sketch of the parts I intend to laser cut or CNC together.  Those sketch elements can then be extruded into body parts and attached further in the design process, while the original sketch can be used for cutting.

If you didn't start that way, a workaround would be to create a separate sketch in a different file that was the size of the bed, and then copy and paste from sketches in your original design.  

[djowen40]

Does your laser software not allow you to click and drag the imported dxf files around?

In the system we use at work once you have imported the dxf you can group all the elements and move them as a block. So we simply post each item separately and import and arrange them in a laser software. 

The best solution to this would be finding some nesting software to arrange the parts for you. I have not played with any so can't make any recommendations.

@michael55SE4's ideas sounds like a good approach if you want to nest everything in CAM. My comment would be (unless I am missing something) this seems to remove some of the advantages of working in a multi-component model space.

The other way would be to simply create copies of your parts that are jointed to the same plane. You can copy and paste components and they will stay linked. You could then use joints to arrange them. e.g. simply grounding one of the copies off to the side of your model and then creating plane type joints to get them all on the same plane. You can then drag and rotate them into position.  The advantage i see in this is that your nested parts remain linked to your model while still allowing you all the advantages of the multi-component model space. 

[michael55SE4]

What advantages are being missed by exporting DXF layouts directly from sketches.

[jcsantilli]

I copied and pasted the components in a single plane. I don't know if that is the best solution but worked.

Thank you guys !

[djowen40]

I am not sure i have interpreted your proposal correctly so i could be entirely on the wrong tangent here. 

Based on your post I assumed you are modelling all the parts in a single sketch, extruding them and then using joints to position the bodies. Is that correct?

If it is then it makes it more difficult to design as the part are all built on the same plane rather than modeled in place. This IMO would make it somewhat harder to design the parts as they are not being modeled in there final position which makes linking the geometry of each component harder.

Your second option seems to propose modelling parts in there final position, which the way i would normally build parts. I have not tried but as far as I am aware copying and pasting from one sketch to another does not maintain a link between the two sketches. This would mean that if you made changes to the design you would have to recopy the appropriate sketch every time you made a change.

This whole thing most likely comes back to the way your prefer to model. IMO the big advantage of the multi-component molding space is that things can be modeled in place and with reference to each other. modelling everything in a single sketch seems to remove some of this advantage. While coping and pasting sketches would seem to generate a lot or work recopying if the design changes.

If I have missed or misinterpreted an aspect of your proposal let me know. I am always looking for better / different ways to model parts.

Cheers.

[michael55SE4]

There are different types of efficient workflows for different tasks.  I used to design objects in place with multiple sketches, but ran into lots of problems.   The advantages of starting with a single sketch per stock to be CNC'd or laser cut include:

1. Adding a part to the sketch is all you need to do--  its automatically cut without having to do anything else when the DXF file is output from the sketch.  You can then extrude and joint it to the 3D model, but that's optional.  

2. If the design requirement specially states that the entire project must be cut on a single sheet to fit a particular machine, then you know that as the first step in the design process.  Waiting to later often means the entire part has to be redesigned from the ground up, doubling your work.  

By contrast, the recommended CAM module workflow requires building 2 3D models instead of one, and the CAM process is disconnected from design, so that changes in your design don't flow through to the CAM setup.

CAM-based Design Change Workflow:

1. Create a new part in 3D space on a floating sketch.

2. Deconstruct the 3D part to place it on a 2D plane, essentially building a second 3D model of the laser or CNC machine.

3. Edit the CAM configuration to include the new part, and any new lines added to old parts.  

I can see my approach wouldn't work for designs with a lot of depth, but my projects are relatively simple for construction out of 4x8' acrylic or wood sheets.

[djowen40]

Fair Call,

I full agree with different approaches depending on the task at hand. 

most of the part i work on have a lot of inter-part relationships so i guess i find maintaining these easier in the 3D environment. 

I wish Auto desk would make there nesting package part of fusion.  https://www.autodesk.com/products/trunest/overview

Many have requested it.

[jcsantilli]

This is the way I did it.

Made the box. Copy and rotated the sides. Them created a sketch and projected all the components. Save it as DXF.

[djowen40]

Looks good.

Happend to bump into this and it seemed relavant so i thought i would link it in. You can then use the DXF post processor and the laser tool paths which would also allow you to compensate for your laser Kerf if you required that kind of accuracy.

[djowen40]

This may also be usefull

https://github.com/tapnair/NESTER