Designing parts for dxf laser cutting

[Anonymous]

Work continues on my DHC-2 Beaver project.  Surfacing is done!

Starting on structure now.  Any hints on how not to screw this up?  After I get all the structure in place, I'll use it to create a .dxf file or group of files to laser-cut the parts from balsa and thin plywood.  Is this easier to do if I make each individual part a component, or is it OK to just leave them as bodies?

Should I roll the timeline back to the end of the fuselage surfacing before I start making the fuselage structure, or should I just charge in at the end of the timeline?

Thanks,

David

[SaeedHamza · Accepted solution]

Hi,

If you want to export your bodies into dxf files for laser cutting I recommend you to keep them as bodies, because there is no benefit in converting them into components for your purpose

Regards, Saeed

[TrippyLighting]

I disagree that you should not create components from these bodies.

You cannot laser cut 3D objects, only objects that are already flat or object that are flattened by some means. The DXF file should only contain the outline or cut lines of such objects and not construction lines, dimensions, or double/overlapping lines.

The best way to achieve that is to create a new sketch on top of the component and immediately stop that sketch. That sketch is "clean" in that it only contains the outline of the objects.

As such it makes data management much easier when the body you want to laser cut is in it's own component. If you activate the component before creating the sketch, the sketch will be created in that component and it is easy to find.

I've done this many times and it works like a charm.

[TrippyLighting]

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@Anonymous wrote:

Should I roll the timeline back to the end of the fuselage surfacing before I start making the fuselage structure, or should I just charge in at the end of the timeline?

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Nice looking model BTW.

To answer your question, I'd roll back the timeline and start creating the structure for the Fuselage after the surfacing for the fuselage. Maybe create an assembly for the fuselage and all the items that make up the structure should be components in that assembly. This will make it much easier to manage your growing design.

Are you familiar with Fusion 360'sR.U.L.E #1 ?

[davebYYPCU]

Great to see the progress, and I agree with Trippy, at least for the last few stages of the process, - if you intend to use the Nester add in.

A word of warning, the formers, or articles, created from sliced cross sections are last, because you need all of the relevant parts to be there before you do,

Continuing with the outside in, method,

outlines, skins, doublers, braces, rails, longerons, trays, reinforcing, lightening holes, servo cable runs, pushrod runs, need to be there in roughly that order, to save yourself lots of circling back.

For our work, I do it this way, I have Components set up for each of the major parts, Wing, Fuse, Tail/s, undercarriage, when you make something name it.

when inside the Component, I make each "Part" a new body, in place.

To use the Nester, I have and it saves some work in larger projects, you need Components for it to work.

To get a former by slicing the model, you need a sketch position, create the sketch with auto project turned on, extrude the former as new Component, done.

To get dxf layouts, create the material blanks, (Components) one for each material, run Nester, move/copy the layout to suit

create new sketch on the face of the material Component, save it as dxf.

Keep us posted...

[Anonymous]

Peter,

Yes, I'm familiar with rule #1:  make a component.

So for this model, I will have roughly 100 component-parts, which seems like a lot of overhead.

My final output will be either one dxf drawing, or series of drawings, that will place the outlines (as you've accurately described) for cutting as many parts as will fit onto standard sized sheets of balsa or lite-ply.  Since I'll have multiple parts on each sheet, and they'll be generally grouped by larger assemblies (wing, fuse, horizontal tail, vertical tail), are components for each part still necessary for data management, or just a good practice?

davebYYPCU (above) makes a good point in that the bulkheads & ribs will be made last after all the other parts are in place.  If the other parts (skins, longerons, spars, etc.) are components, will that make it more difficult to slice them up later when creating the bulkheads & ribs?

Thanks,

David

[Brady_Fulton]

My process for a very similar situation is that I follow Rule #1 making components as my design grows and for my DXF outputs, I always generate new sketches with my base assembly activated and my history marker at the end of the timeline. This way any edits I make inside the individual components will be translated into my DXF output. This procedure does bring up two features that would be really nice:

1. Batch output of selected sketches to DXF files

2. Default output file name to the sketch's name inside the assembly

[TrippyLighting]

To answer your question, yes, I still would make all of these parts components.

For manually  arranging then on a piece of stock I would then create a component/assembly that I call "Layout".

Then within that assembly I'd create a component with the dimension of that stock and ground it.

The next step would be to copy paste all components I want to lay out on that stock into that assembly and then create planar joints between that stock and the pieces.

THen  they can be arranged on the stock and finallly it add a position capture feature to the timeline to store the final coordinates of these components.

The manual nesting script might help with the last steps.

https://youtu.be/7SY367qt3YQ

The advantage of the additional copy/pasting of components is that the original components will remain in context in the design. If the design changes so will the coopy/pasted components wI'll also reflect these changes. 

[davebYYPCU]

will that make it more difficult to slice them up later when creating the bulkheads & ribs?

I don't think so, as long as they are turned on, the Project Command should find everything, but I could be wrong there, as I am normally slicing in the same Component, because all my bodies are in there, but, you may have to slice from the root component if there is a problem, that should work, @TrippyLighting, can you shed any light on the process?  Your too quick Trippy, I was still typing.

Later....

[davebYYPCU]

Sorry, I just found your post after writting the question above, so from the root componet it will work, thanks for that.

Agree with 1 and 2 by the way.

[TrippyLighting]

I am not entirely sure what you guys  are referring to as 'slicing'.

Either way, the Sketch->include/project commands and the Modify-> combine tool  will work regardless what components Bodies are located in.

[davebYYPCU]

Slicing is our term for creating a sketch, position is relevant, with Project > Intersect for the outline of the "cavity" at that location to fill with an extrusion, plywood or balsa, to then be exported for laser cutting,

Yes I have used the Nester program near the end of my workflow, when I have all the "to cut" Components.