What workflow should I be using to connect the ends of 2 parts (for making a case)

[OceanHydroAU]

I'm stuck trying to neatly join the below: (also at https://a360.co/3qIn5e6 )

While I semi-solved (not useably) one side of this, I've got no idea how to loft to the side of the circle - what approach should I be using ?   (FYI - the "circle" is for a plug to screw into, and the square is for a switch)

I managed part of the above by creating control-point-splines for rails, then lofting 2 flat profiles.  It's not perfect, because (can't be seen in above) there's a slot in the back for gluing 2 sides together later, and that slot mucked up.

I guess part 2 of my question... how to model a "case" which is to be glued together later (to be waterproof) which has "funky ends" ?

My end-goal is to create a 2-part shell for leg-mounted scuba thrusters (DPV) so that I can fit all the electronics into the top (including the switch and charge plug which this loft issue relates to), and then glue the bottom on to make it all watertight.

(Ignore the "nose" in the above - I ditched that idea to have a 2-part shell instead - top and bottom only).

Above shows what is contained

The loft (or however else to make this - I also tried surfaces and thickening) I'm trying to do is for fitting the above into.

Ideas ???

[OceanHydroAU]

Also, unrelated - my plan is to FFF 3D print the case in PLA (heat-sensitive colour changing, so I can quickly see any possible heat issues), then to "dip" the entire case into resin to waterproof both sides, then fit the electronics, and join the halves by dipping it all again into resin (to seal the join at the same time as waterproofing that again).  I'm also spraying the electronics with waterproofing lacquer, and considering fitting the batteries into their own separate waterproof plastic heatshrink pouch before fitting)... and chucking a few tampons inside in the vacant spaces... 

Does anyone have waterproofing experience?  Does the above sound like it might work?  (The thrusters are wireless, and the charge+data plug and switch are IP68 waterproof already - although I don't trust that, so I'll probably "pot" both of those from the inside after wiring as well).

[davebYYPCU]

Can Loft the surface of the outlines, but not with your sketches, as the outlines are not chain connected (white dots).  This one does not thicken, and as there are no rails, I did not get curved lofts like your picture.

[TrippyLighting]

It depend on what "quality" of geometry you want to create.

I think that you've already started off on the wrong foot. I's use a sketch to "reserve" some area, but then would model a shape that aims to be aware of that area without restricting myself rigidly.

I would not try to connect two final geometries.

However if you do attempt to loft, very rarely is it a good idea to loft  2 final, filleted shapes. All filets should be removed before lofting and then reapplied after lofting.

Are you able to share the model?

Only the outer shell/ surface is needed.

[TheCADWhisperer]

@OceanHydroAU 

Are all of your sketches fully defined? (Hint: The correct answer is - no.)

I will have to start over from scratch.

Where are your dimensions???

Edit 1: As I start to go through this - I am finding a lot of Tangent constraints are missing?  What happened to your constraints?

Edit 2:  This is too rough for me to spend time on.

Are there any unresolved issues indicated in your Timeline?

[OceanHydroAU]

No fillets in there (it's just lines and arcs to wrap around the batteries).

The original is constrained (I did a "copy" and "paste" of the 2 sketches involved into a new project to share - the original is too huge).

I don't need my own problem solved (thanks for trying!) but I am interested in trying to figure out what workflow to use.

I basically need a "shell" of a constant thickness (e.g. 2mm) and I want to nicely join a hollow shape (the body) to a perpendicular flat end (the panel for the switch and plug) where the shapes involved are more complex than plain squares (e.g. one is a circle).

Maybe the only way is to spend all day sketching a pile of splines for rails in 3D ?  (I did semi-try that already, but Fusion360 is unhelpfully creating gaps between sections, which I then cannot fill in...)

[OceanHydroAU]

Thanks for trying!!  I'm looking to learn how I should be doing this (joining perpendicular non-trivial shapes).  I copy/pasted from my project, hence all the missing constraints ... what was your approach going to be?  I assume starting from the sketch(es) somehow? (which I did not think to try - I was starting from the body surfaces)

[TrippyLighting]

Those are fillets:

I don't need my own problem solved (thanks for trying!) but I am interested in trying to figure out what workflow to use.

This isn't merely a workflow problem. What I failed to explain in my 1st reply is that this is a topology problem.

The 2 shapes you are trying to connect simply have way too different topologies. Once you've worked out the topology problem, the workflow will present itself naturally.

[OceanHydroAU]

not fillets - they are center-point arcs (can a sketch even include fillets at all?) - all the bodies in question are extruded from regular sketches using only lines, fit-point-splines, and center-point arcs.

I don't know if this is the right way or not, but I've almost solved this as follows:

I created a second sketch of the case-end offset by some random amount, then joined all the points with lines, in order to get a bunch of lines that I can later use for constraints of my fit-point splines.

I then joined the end to the switches with splines using 3D sketch.

I next added lines on the switch end at all teh join points, so I can also constrain the other ends of the splines

Then I used the "parallel" constraint on all the spline handles.

I created some surfaces and used those to split the switch place in a few strategic places (around the circular part).

And finally I can loft the case-end sketch to the side of the switch-panel body, using the splines as the rails...

[TrippyLighting]

An arc that is terminated on each side  tangentially by a line or curve is a fillet. If you want to learn, you need to start listening. I am out as I lack the time and patience to talk to talk to brick wall.

[OceanHydroAU]

The solution was to pay very close attention to the loft command dialogue - it often guesses the wrong tangent, so clicking the "change direction" icon is needed to get the lofts to go in the needed direction.

I had to change my idea about using only 2 pieces, into 3 instead - there's no room among the switch and plug parts to include a case-seam without causing a "bulge" that would press into the users legs - so I've opted for a separate endcap instead... which should make the plug soldering easier anyhow.

Fillets (if you want to call the outside of 18650 batteries "fillets", rather than meaning the Fusion360 operation by that same name) were a red herring and as far as I can tell totally irrelevant.

If you found this post in google and are yourself stuck doing something similar, post a reply here and I'll upload a screencast.