3D Modelling in Fusion 360 - beginners' guidance...

[Mattlow]

Jamie

 

One thing I am finding is that each time you get to something you can't work out how to do, type a simple question into Google and you'll usually find multiple videos and threads from fora that cover the subject.

 

I am also finding that it is common to think you've gotten somewhere, find out you haven't done it quite right and then have to re-do it... at least in CAD it is somewhat easier than, say, stripping all the paint off a model you've messed up.

 

I've done some of the basic intro tutorials and much of it has half sunk in... but I think there's a need to try something you're interested in to keep up the motivation... even if it turns out a bit crap, it is a sign of progress and that's what I certainly need. If you look at One Man Model and Dora Wings designs, they look just like what we're doing.... but much better... so there's a clear progression between where we are and where they are... as you say, it just takes time, patience and perseverance...  

 

Not sure if I have enough of those yet, but time will tell.

 

Matt

[qn30jEkPz7]

I hate youtube videos with a passion - I might spring for a copy of this though

https://www.amazon.co.uk/Fusion-Makers-Lydia-Sloan-Cline/dp/1680453556/

 

I’ve used their electronics and arduino books before and found them useful

[Schwarz-Brot]

@Jamie @ Sovereign Hobbies Let me spare you some time... The linked diyodemag tutorial is a good starting point if you come from nothing. The first 3 parts are very helpful to get to grips with the concepts of parametric modelling. Rendering is not important, you can skip that one. Part five may be of interest in some special cases, it essentially teaches how to use (and abuse) the spiral tools. Part six is probably not at all relevant - didn't read through.

Part 3 might seem like very useful, but don't be fooled. Building models by blending sections is an operation with very little control, not at all parametric. So you might as well leave the realm of parametric modelling and enter the world of sculpting tools. With these you can control every aspect in every dimension. Not easy to get used to. I'd highly recommend to follow the official tutorials before drifting off to youtube or written sources. It is important with these tools to really understand what they are meant to do. This series is essential imho: https://help.autodesk.com/view/fusion360/ENU/courses/AP-C-CONCEPTUAL-MODELING-FUNDAMENTALS

If you follow these videos you'll quickly see this is what makes fusion really powerful for our purposes.

 

Edit:

@LostCosmonauts I have plenty of the make books, but to be honest I hated most of them. They are usually helpful if you start from nothing, but leave you with more questions then answers when things get more involved. My main concern is they are usually written by selftaught "experts" and more often then not contain solutions that work in some way, but are often done in a questionable way from a professional view and thus get in the way if you start digging deeper.

 

The diyodemag tutorial linked above contained some things I'd do very differently as a trained CAD professional, which showes the author is not above experienced hobby level. I found no real mistakes, though, just awkward solutions to get to the results. But they work and would do so under all circumstances, so no worries from my side.

 

 

[Mattlow]

Hmmm... I wonder if it isn't something you'll have already surpassed?

 

What i like about Googling is the immediacy, ask a question and pretty much get a list of different answers...

 

I am having a really crap time trying to get my profiles to line up with the rails (profile) or vice versa. I should have realised when I was drawing the profile because I wasn't getting the little green square which means the point you are about to make is snapped to the point of the profile. I suspect I am not actually drawing the profile on the same plane as the edge of the sections are sitting on (if you see what I mean.

 

This is where the perseverance bit comes in... :). I need to make sure I am setting up the drawings/canvas correctly. I'm sure I'm making a really basic error here...

 

Ho hum..

[Schwarz-Brot]

@Mattlow Fusion sometimes acts funny when placing sketches. It often happens to me that I select a plane to place a sketch on, then place some geometry in that sketch and find it to be snapped to some part far away from my sketching plane. This is a behaviour I really cannot figure out and don't see with Inventor.

It might be of help to you to manually place constraints. I think the "coincident" constraint would be of help here: select the constraint in sketching mode, selekt the point you need to fix to another geometry, then select the geometry. A point can be snapped to other points or to straight lines. If you need to snap it to curved geometry it may work in some situations, in others you'll have to project the geometry first, then snap to the projected line.

 

Hope that helps or at least gives you hints what to google next 😉

[qn30jEkPz7]

That’s really helpful @Schwarz-Brot - I don’t have any background at all in CAD or design so I’ve been feeling my way based on the Autodesk tutorial and trial and error (lots and lots of). I had hoped that books and magazines would have filtered out the better

[qn30jEkPz7]

13 hours ago, Mattlow said:

I am having a really crap time trying to get my profiles to line up with the rails (profile) or vice versa

This is probably a klutz approach but I tend to include guide horizontal and vertical lines in each profile which intersect the outline where I want to snap the guiderail to. I’m not sure if it is sheer placebo or a cargo-cult approach but I think I get fewer errors of the kind you describe and even when they crop up it makes doing the manual coincident constraint to fix it a little easier

Edited July 29, 2020 by LostCosmonauts
Utter gobbleygook

[Schwarz-Brot]

Your klutz approach is actually not too bad at all. If I have to trace a 3d curve in Inventor I'd usually work with splines to define the outlines with some control. Freeform modelling is not allowed at my workingplace. To get fixing points my goto approach is as follows: Add a plane for every known crosssection and sketch that crosssection on this plane, say from nose to back of an airplane. Make sure every sketch is completely fixed by constraints and measurements - this is key in parametric modelling!

Next is Crosssections from ground to top: create planes, add the crosssections. To give them something to snap to you need to project the points where the vertical "slices" cross the recent plane. These points are your anchoring points to lay the spline along. as described in my post above.

 

This is how I do it in Inventor. The workflow in fusion might be slightly different. I personally would always opt for the freeform workspace, as it gives better control and we don't need solid models for printing. Maybe I can do some writeup on this with an ongoing project.

 

Edit: In fusion you can open the projection toolbox by pressing [p] when in sketching mode. If this does not give you usable points you may have to leave the sketch and manually place points at the intersection of sketch and plane. These points are available from the same dropdown menu that lets you set workplanes. These points can then be projected in the sketch or maybe even catch automagically.

[Mattlow]

@Schwarz-Brot

 

Many thanks.

 

Lots of stuff to get my head around. I had read that constraints are very useful/important in F360, but hadn't really come across anything describing their use. I shall have a read around as they sound more useful than their name suggests to the layperson..  In fact I was sitting blankly last night thinking how can I tell F360 to move this profile by making this point co-incident with tat point over there - sounds like that may be a constraint..?

 

Ta

 

Matt

[Schwarz-Brot]

Yes, that is a constraint. Constraints are only available in sketches AFAIK. To define a sketch you work with dimensions, quite obviously, but it is in most cases more elegant to use constraints as well. Things like parallel and orthogonal orientation, centering, tangents and coincidence and some more are available. These help you aligning geometry in sketches without breaking out the calculator. Some things can only be described to the CAD system by constraints - for example coincidence can be calculated and given by numbers, but to make a closed outline that can be extruded you need the coincident constraint.

 

But applying a sketch or a canvas to a plane is a constraint as well, if you think about it. If you work with multipart assemblies and apply joints these are also constraints.

[Mattlow]

Hi all

 

I know you hate YouTube vids Alistair, but I just came across this chap and I have to say just watched two really clear and unfussy explanations of constraints and dimensioning. I mean I went from 'what are these things' to 'oh right, they're totally logical and look really useful'. He usefully explains that they're also automatically applied to various aspects of the sketch and, if you don't know what they are, can give you hassle.

 

Two vids:

 

 

 

 

I like his style, I'm going to do the whole course before I start anything else...

 

Matt

[Mattlow]

Just an update on the above. His series is learn F360 in 30 days, well 30 videos. I am on number 6 and I can't believe how much I'm learning (trying to retain it). He's really clear and thought the  objects he models are mundane, the techniques and functionality he passes on is excellent.

 

Highly recommended.

 

Matt

[Mattlow]

Hi all

 

@LostCosmonauts and @Schwarz-Brot I am getting closer to having another go at actually modelling something.

 

I have a question which is probably answered through experience rather than in a tutorial.

 

If my output is principally aimed at 1/48 scale, should I model in that scale, in 1:1 or somewhere in between.? There must be pros and cons in choosing a scale at which to model.  Any views?

 

TIA

 

Matt

[qn30jEkPz7]

6 minutes ago, Mattlow said:

Hi all

 

@LostCosmonauts and @Schwarz-Brot I am getting closer to having another go at actually modelling something.

 

I have a question which is probably answered through experience rather than in a tutorial.

 

If my output is principally aimed at 1/48 scale, should I model in that scale, in 1:1 or somewhere in between.? There must be pros and cons in choosing a scale at which to model.  Any views?

 

TIA

 

Matt

I normally model at the 1/72 size I intend to normally print so that I can read off what dimension each element is going to be. I find it helps me visualise what it’ll be like in real life and judge how printable and mechanically robust it’ll eventually be. For 1/48 I’ll likely take the same base model, tweak here and there then print at 150%

[ScanmanDan]

Matt I also do most of my work in 1/48 scale.   I like to draw to output/printed size, that is, all real dimensions reduced by 1/48.  I work in metric so this is easy.  Just input the dimension and multiply by 0.0208 and Fusion 360 will spit out the scale dimension.  Even easier you can set up all kinds of  'parameters' under Modify/Change Parameters.  I usually set a unit less parameter of 'A' to 0.0208 at the start of all drawings in 1/48 scale as my ' Scale conversion'.  Thus type a*385 into a dimension box and you'll get 8.008mm  .  Same goes for converting inches to mm (a*11.5*25.4= 11.5 inches into scale mm  )  I do this mainly because I like to have the overall dimensions right but lots of the tiny details like latches and hinges need to be slightly oversized to print well.  I have a self imposed limit of features no smaller that 0.3mm.  This work flow lets me keep the drawing to scale, which makes importing drawings and pictures as canvases easier, and controlling that real world min feature limit of 0.3mm.  Parameters are also a great way to set up dimensions that you always use, say a 0.3mm offset  
Additionally don't forget that the dimension boxes in Fusion 360 let you input all kinds of formula so let the program work for you.  1/2 and 1/3 stuff easy, a dimension less an offset or a centreline distance, easy.  Have fun and I hope this helps.  Fusion 360 is so neat.

 

 

Edited August 1, 2020 by ScanmanDan

[Schwarz-Brot]

The answer is easy: It depends.  As said above - small scale detail might need to be oversized- I had this situation when I did the wire lock bolts. These were modeled to the printed dimensions to get as close to the limits as possible. Also, they did not resamble an exact part in reality but some more generic part so to say. Thus the overall look was more important than exact "real" dimensions.

 

If I model a real part and have its real world dimensions I model to these dimensions and scale down later. This way I have full detail no matter what scale I end up with. This is the goto-approach usually in a commercial setting, but to be honest I think with models it is wiser to model to the intended scale, as you can then easily decide visually how fine the details need to be modelled and what can be let out.

[MarkSH]

Remember if modelling 'at scale' to take account of wall thicknesses.  I had two scales of wheels printed (Shapeways) for a starter trolley (modelled in Rhino3D) and had to make substantial changes so that the print was self supporting at 1/48. The 1/24 scale was less critical for obvious reasons, and I even managed to get the valve stems printed, didn't expect them to work.

1/24........

 

...and at 1/48

 

I can highly recommend Rhino3D especially the later iterations version 6+. Blender is also a very good modeler and can be made to turn out models for printing....its free too!

 

Cheers,

 

Mark.

[Mattlow]

Thanks to all of you for that...  I am almost ready to re-start.

 

I think the Mew Gull drawing was too poor. I'm looking for something better and maybe an aircraft that is better documented..

 

I have some ideas..

 

Matt

[qn30jEkPz7]

Just saw this new update which adds an embossing function which may (hopefully) make adding panel lines and features much much easier

 

https://www.fabbaloo.com/blog/2020/8/12/autodesk-emboss-feature-in-fusion-360

[Bozothenutter]

Awesome that this area seems to be getting some action too!

Just started with fusion myself, saw the oily bits of a Mark IV tank and thought :" with all that symmetry this can't be too hard..."

Working on the final drive

 

 

Trying to work on a cylinder block as well, but keeping that  in basic shapes for now, as I cannot find any measurements anywhere.

[Stephen W]

Looking good, keep at it and it will become easier.
 

I must admit it looks like fusion is still adding features to it so it should get better, also finding good image references is key to a good model.
 

I may have a play with fusion to see how easy it is once I have finished my model in max.

 

[FZ6]

I've spent a week learning fusion 360 and must say, I really like it. I have almost finished my first drawing.  I've watched a few youtube tutorials and taken it from there. I had an email last week about changes to the free  version and that some features were being removed.

 

https://www.autodesk.com/products/fusion-360/blog/changes-to-fusion-360-for-personal-use/

 

As a new user of Fusion 360, the biggest issue as a result of the change to me will be to only have 10 active documents at one time but I can get around this by archiving projects that I'm not working on. Other restrictions seem to apply to not being able to exporting certain file types and more advanced CAM stuff which doesn't really affect me at the moment so I'm going to continue using it but I thought I'd ask if other users of Fusion who are using it for 3D printing are going to be affected as well?

 

Regards,

 

Mark

[Bozothenutter]

small update....