Trying to design a 3D polygon surface for 3D printing

[Anonymous]

I'm trying to create a 3D polygon surface for some objects I need to 3D print. My main problems are two. 

1. How do you get sketches to snap to consruction lines? Only way I manage this, is to move / draw exactly on the grid, but as I need to design in incrementals of 0.15mm or 0.2mm (printing layer height) that is less than ideal. Also, it requires me to constantly zooming in and out just to find the grid snaps. 
2. I want to "anchor" the sketch points to construction planes, so if I need to change the hight of the planes (basically redefine the height of the polygons to ensure the best printing quality) I need to draw all my polygons and afterwards just adjust height of my "layers" / planes. I only mange to do this with none 3D sketches. 
   
   

Did a short screencast to illustrate my problem. Sorry for the zooming, just wanted to show my problem (almost seasick after a few hours zooming in and out to find the "snaps". 

[Anonymous]

Think I managed to figure some of it out my self. Found the sketch point. If I add that to my two planes and then do my 3D sketching, they will connect and influence the shapes when I redefine my planes. Is that the right way to do it? 

[davebYYPCU]

What?  

You will do better with no grid, 2d sketches, normal lines and dimensions.

More sketches and learn to use the Project command.

Might help....

[davebYYPCU · Accepted solution]

This might help....

Step up the time line, Right click on the icons, Edit feature to find the settings.

[chrisplyler]

In your second Sketch, just Sketch>Project>Project the desired intersection from the first Sketch. This will put a point in your second Sketch that is "linked to" that intersection, but on the Plane of the second Sketch.

[Anonymous]

Thank you all for trying to help a complete beginner to Fusion360. It's my first real object 🙂 
Bought a 3D printer, downloaded Fusion and ran head first into a lot of fun problems 🙂 

I managed to solve what I was trying to accomplish, but not sure if it's the right workflow. It's only for my own personal production (3D printing computer modding parts) so it doesn't have to be 100% construction accurate. 

I added sketch dots on each joining points on the sketch surface I wanted. Like dotting out a layer hight pattern. I then just did one 3D sketch joining all the dots into the shapes I wanted. Now when I change construction planes the polygon changes. 

My main consern was not being able to shift the layer hights (the polygon surfaces) and influence the shapes, as not enough height differance will result in a flat printed surface. To much height it looks more like an egyptian pyramid rather than a flat polygon surface. 

My new problem is that once I manage to create the shape and look I want, I can't edit them. For example, I want to extrude a rectangular shape into the back of it (3D material savings and hole for screws) and it is just a patched hollow surface. I also have some stich problems.

Found a tutorial where someone creates a Polygon vase and just use Shell, but that isn't working. 

This is the look of my shape currently. 

[davebYYPCU]

If you are accurate enough, the stitch should work ok, If working in surfaces, finish all as surfaces, and then stitch.

When you have  watertight set of surfaces, it should stitch to a solid, then extrude the base as Extrude join, drill holes, last.

Attach the file, much easier to demo with your data.

Might help...

[Anonymous]

Sorry for that, here is the file (be gentle ) 

[davebYYPCU]

Window select the whole model in the Stitch Command

Won't stitch as is, the red edges are in error.

 Using Section analysis, there is an internal wall in there somewhere, and it will cause trouble..

Your design, I don't want to mess with it.  Work towards external surfaces only, Trim, Delete, Patch as required.

Might help....

[Anonymous]

ah, it's an internal surface, that explains it. Think I manage to create that when working to do the cutout. Will just redo it from scratch and hope it will be less "messy". Appreciate the help, tyvm