Help on how to make a part in fusion 360

Neowise

Hi all,


I'm very new to fusion 360, which, if you didn't know is a 3d modeling software that is free for personal use (hobbyists like me).


I have been struggling for ages now trying to model this one part.

Its called a twisted chain link.
Its a link like this,





And you put two bars into the link and give it a twist.(roughly a 30 degree twist)



and it ends up like this.





I can't find any options to manilulate my link in the way i want, and chopping out the center straights and twisting the curves 30 degrees and lofting them back together, while is my best attempt yet, is not correct either.

I don't have the experience with sketch desigh to be able to 3d path it and create a pipe of the path, which i think would be the best solution, but i just don't know how to make a 3d sketch, I have the oval in sketch, but i cant seem to add z axis changes, it just ignores my input when i try to move the points up and down the z axis.


If you know how to do this, can you tell me the next step after mapping out the oval in the xy plane, how to i add z dimensions to the sketch.

Also, the part is symetrical, so only 1/4 of this object needs to be sketched, as it can be mirrored thru the x and y plains.


Also if anybody else is struggling to make a part in fusion 360, hijack away, as it'll only help me learn too.

Neowise

Okay, so a problem shared is a problem halved is really a thing.

I don't know if it was just because i asked for help or what, but i think i just solved my own problem.

so, i created a new sketch, and instead of before, trying to add points in mid air, i created lines up to where the points wound be.

I then mappped a few points on that path and routed a spline through the points.


then piped it.




seriouly chuffed right now, as i can proceed with my model that i have been stuck with for ages.

Neowise

Definetly not there yet, but a hell of a lot closer.




The plan show the biggest errors in my method, I am not getting any twist.

Neowise

and i'm back to being completly stuck again.

It just seems like i can't do what i want it to do. some way to combine these two things.

The link body, and the twist.

2Pi3

Don't know about Fusion 360, but here's my attempt at it in Solid Edge, you might be able to take a similar approach in Fusion.

youtube.com/watch?v=ONqMqDRtffk

Siemens offer a free version for Hobbyists
solidedge.siemens.com/en/solutions/users/hobbyists-and-makers/

_ptashek_

Neowise wrote: »

and i'm back to being completly stuck again.

It just seems like i can't do what i want it to do. some way to combine these two things.

Would projecting the chainlink curve onto the bend surface and then doing a rail and guide sweep not do it?

Neowise

_ptashek_ wrote: »

Would projecting the chainlink curve onto the bend surface and then doing a rail and guide sweep not do it?

How do I project onto the twisted surface? I think i have to make a sketch on a plane.


The twisted plate shifts from one plane to another, and i don't think i can project anything onto it successfully.


I've attached the f3d file with my failed projection onto surface attempt.

Overheal

see this vid. Some of the technique should translate to F360

https://www.youtube.com/watch?v=g8s2qHVGK-o

Neowise

Overheal wrote: »

see this vid. Some of the technique should translate to F360

https://www.youtube.com/watch?v=g8s2qHVGK-o

Wow, flex / twisting is the feature i want......
will have to research this and see if fusion 360 is capable. ( 2:50 in the youtube video )

mr potato head

A twist or flex approach could be achieved using the form tools rather than using standard solids

• Create a sketch the flat shape of the link
• Use Create Form>Pipe to create a flat link with the sketch as the path
• Select the segments you wish to twist and use Edit Form at the top to allow you to Transform the segment. Before you transform check the Soft Modification option to smooth the transition between the transformed and stationary segments.
• Repeat for the other end of the link
• You might need to experiment with the transition distances etc to get the shape you want.

Neowise

mr potato head wrote: »

A twist or flex approach could be achieved using the form tools rather than using standard solids

• Create a sketch the flat shape of the link
• Use Create Form>Pipe to create a flat link with the sketch as the path
• Select the segments you wish to twist and use Edit Form at the top to allow you to Transform the segment. Before you transform check the Soft Modification option to smooth the transition between the transformed and stationary segments.
• Repeat for the other end of the link
• You might need to experiment with the transition distances etc to get the shape you want.

Absolutely perfect. Thank you very much Mr. Potato Head.