Loosing Dimension when moving z level?

[Fusion90]

Hi there,

Im super new to fusion360, but i’m starting to get the workflow. I’ve been primarily working on sketches and getting everything right precision wise. I’ve noticed a problem and hope that someone could tell me why its happening.

On my base “layer” sketch. I drew some circles, but since the base shape a square box is going to be extruded up 2mm. I moved the circles up 2mm so that they will be on the “surface” of the now 2mm high square. I noticed that when i moved them up, I lost my dimnsion info, so i cant resize them anymore if I wanted to. Am i doing this the right way or is there the CORRECT way I should be extruding these shapes?

I want the base 2mm thick, then I wan the circles to go up 5mm. Should I have just left them on the base z axis at 0 and just extruded them 7mm rather than 5?

[Mirth]

So let me get this right; you’re drawing 2 circles and a base on the same sketch and you want the circles to rise above the base by 5mm?

Ok, so either extrude the original circles by 7 and choose “merge” or whatever the equivalent is or draw the circles onto the top surface of your base and extrude by 5. Try to avoid moving elements of a sketch between planes. Don’t forget if you need to translate dimensions across sketches you can use the “project” function.

Hope this helps

[Fusion90]

Thanks for the quick reply. I guess I was going about it wrong. if you dont mind me asking, what is the problem with moving elements on different planes in the same sketch. In my head I “think” (clearly incorrect) that you’d want to put them on the z axis where they should be moving from. I understand what you’re saying though… I’ll give it a try, i’m not sure if Fusion has a merge.

[Mirth]

No problem! I’m familiar with several Autodesk programs and Fusion isn’t that different so it will have a merge function. When extruding a sketch to a 3D shape you can merge with existing pieces, cut through them or keep the intersection only.

Sketches are 2 dimensional “plans” of what you want to do. Think of it as a sheet of paper. Cutting out a piece of that paper and holding it above the rest is risky and can lose accuracy and dimensions. You should be able to move FULL sketches but not parts. Really, avoid it as much as possible, use project and delete old sketches.

If you have any complex work you need done and aren’t quite ready to handle yet let me know! I do some work on CAD commissions - it helps pay for university!

[Fusion90]

Thank you for the further clarification, its making more sense now. Your paper analogy was spot on. I’ll keep my sketches as my blueprints and try and merge/project when dealing with anything above the plan. Let me give it a go. I wouldnt mind help, but i’m kinda broke so I sadly cant help you with your Uni bills…

[Mirth]

No problem, glad to help! Remember you can make new sketches on flat surfaces of your model, so don’t let that limit you. you can also use more advanced “work plane” features to project onto curves and stuff.

I understand your situation! Tell you what, I’ll help in exchange for good credit. Just keep me in mind if you meet anyone who may be interested in my services. I’ll help anyway but…

[Fusion90]

Will do! BTW, i think I figured it out. I *THINK* the parallel to the merge function you referred to is the operation called “Join to body” by default every time you extrude it creates a new body. For what I’m doing, all these circles are becoming posts on a flat surface so I want to have them be part of the base as a collective item. Once I have this done, i see i can export directly to STL. Is it really that simple to send it off to a 3d printing service??! I know it cant be that easy, it just cant.

Speaking of, do you know of any affordable printing services. Ponoko, shapeways, etc? Any diamonds in the ruff you’ve come across? Nothing exotic material wise, PLA/ABS?

[Mirth]

Yeah, that sounds right. It really IS that simple, hahah! But that’s not where it ends, depending on what you want to do with it the infill etc will be important.

I actually just set up my hub today, I’m printing clear PLA (which is highest purity as PLA is naturally clear) and I’m looking for reviews. So if you want to run your STL via my hub I’d be honoured! I’ll help choose the best infill and wall thicknesses for your particular use too. I’ve not actually got a feel for the pricing yet but if it feels too pricy let me know and I’ll see if I can bring it down a bit for you

I’m in Edinburgh, Scotland, so that may be a factor when deciding.

Anyway, its an open offer, let me know!

From memory default first print price is £4 minimum to cover the startup costs.

[Fusion90]

Thats pretty sweet, I appreciate the offer, but Scotland would be a bit expensive I think for shipping. I live in Boston and have a bit of services around here thanks to MIT and all the other tech schools in the area. The print will be big too… about 585mm wide, so its gonna be $$. I made the walls only 2mm thick per some forums I read and put a .5mm gap between the parts that have to slide along each other.

Now that iv’e got the hang of how to properly utilize the sketch and extrude. If I create a extrude “structure/form/part” not sure the proper term. If i want to see how the different parts fit, can i just move the ‘bodies’ around and not mess up my sketches.

[Mirth]

Well, had to offer! .5mm clearance should be plenty. It sounds mechanical so I’d suggest you use 40% infill.

My guess is that your sketches will stay in global space and not move with your object. You will probably be able to move your objects along fixes lines in the X Y and X direction. Last I saw on Fusion360 you can make “assemblies” where you can put the pieces together and even do some basic simulations but that does’t sound completely necessary.

Don’t forget there’s always CTRL Z

[keebie81]

You can still resize them. move your timeline to before you moved them and then adjust the dimensions. Thats what makes the timeline such a great feature

[keebie81]

You should fix your z axis wobble before offering print services. Dont want to have your hub filled with bad reviews from poor quality right away. Besides you will be losing money since you would need to give refunds for that print quality. Take the time to learn your printer and get great results first.

[Mirth]

You say it as if I literally just got my printer and set up my hub. That’s not the case. I’ve spent a lot of time working with this printer and I’ve spend months before hand researching everything I could to design my foldable printer. With that knowledge I was able to assemble the entire printer without the instructions (until the motherboard, where I was then able to hunt down exactly what board it was and wire it up). I recently redesigned the X axis assembly, printed out my parts and reflashed the board successfully the first time.

my Z axis wobble is nearly completely eliminated. I’ve got the ends tapes and clamped in self-centering couplers and really the only improvement I can see to make now is to add proper lead screws.

the review I got for the test print was 4.8/5, 4/5 for quality in the breakdown. I know it’s not perfect but I don’t exactly have the money to get it to 5.

Besides, I take pride in my work and where necessary would reprint or do some light finishing.

[Fotogravinci]

You could sketch and extrude the base first.

Then create a new sketch, select the face of the base and draw your circles on top of that. Select and extrude the circles.

Also on the left pane you’ll see your sketches in the component tree. If you want to change your sketch parameters you simply double click on the sketch and adjust, add or remove what you want. And the rest of the timeline will take the change automatically.

Hope this helps.