How to create a collet or twist lock

[ian.byrne]

Hi,

I'm new to Fusion 360 and coming from mesh modelling. I've a week in of consuming videos and tutorials and am getting to grips with the basics but have been trying to find a solution to create a twist lock mechanism to allow two telescoping cylinders to extend and lock in place without success.

The closest thing I've found to what I want to create is this:

https://www.thingiverse.com/thing:1079202

Now I'm trying to make my own for 3D print and wonder if anyone could share a workflow for it please. I've got this far..

inner sleve

..but lack the knowledge to create both mating parts and test the joint properly. Would be great if an expert could walk me through a solution!

Many thanks 🙂

[Oceanconcepts · Accepted solution]

It looks like you are about there, and have done fine. I’m sure there are many workflows, and not knowing how you created the part you have is a disadvantage. But assuming you have only the solid model you show and no previous sketches. I would probably do a construction axis down the center of the tube, make a plane along that and create a sketch on that plane and project a section of the part into the sketch. Then offset those lines to whatever clearance you desire for the outer clamping section, finish the rest of the profile and do a revolve, then model the threads. It’s not really different from what you have already done, just inside-out. Do this all in a separate component. It will make things easier down the road. 

I’m a little stuck at “test”, though. If what you are asking is about how to test gripping power when this is clamped down, I don’t think Fusion can do that. Unless I have missed something in recent updates (possible) simulating flexing materials is not a strong point. 

Maybe say more about where you are feeling stuck? 

[ian.byrne]

Hi Ron,

Thanks for taking the time to reply, I'll look into your suggested methods for creating the opposite part, I've come across the project tool in one tutorial but it only skimmed it so will delve into how to use it for this case - that is where I'm stuck at the moment, matching a piece to the one I've created.

In terms of how I made the inner piece, it was a very basic cylinder, screw thread onto that, then another sketch on top and extruded that at a slight inward angle, then created a tangent plane and drew a rectangle for the cutout and extruded through the top section, turned 90 degrees and same again. I'm sure there are more elegant ways to do it once you know how 😉

In terms of test, I was thinking primarily of whether the two pieces fit together, but also was interested if there are more advanced options than joint such as clamp as you suggest but then it is probably material dependent anyway. If I can make the two fit together in the program the rest will be a bit of trial and error with the 3D printer.

Will keep exploring and try your suggestions and see how I get on.

Thanks,

Ian

[PhilProcarioJr]

@ian.byrne

See if this is close to what your after, and if it is I can do a screen cast showing how to do it.

I left 0.005" clearance of course the amount of clearance you will need depends on your 3d printer and how accurate it is along with the type of material and it's shrink properties.

In manufacturing at a machine shop you would not do it this way, but I have found that depending on the type of printer you have you can not always use real world manufacturing models because of the tolerance requirements.

[ian.byrne]

Hi Phil,

That would be incredibly helpful, thanks so much for taking the time to do
this.

I think it is just what I'm looking for, but even if not it will certainly
help me ramp up my learning and get me a lot closer! I'm really happy how
far I've come in a week but as with speed learning any software it is a bit
like Swiss cheese, some parts very solid but then also some gaping holes!

I'm a Brit so working in mm and I think the tolerance may need to be bigger
but I could try and print it and see what happens and obviously once I see
the method I can make my own version with adjustments. I've attached images
of what I'm trying to recreate in case they are useful but I think you've
probably figured it out already.

All the best,

Ian

[PhilProcarioJr]

@ian.byrne

Until I get time later tonight to make the screencast you can step through the timeline to see exactly how I made this.

It's a pretty simple workflow actually. I will post the screencast later today.

One thing I didn't do that is very important for multipart assembly/modeling files, is I did NOT create a component for the first part and I should have but I quickly wanted to see if this was what your after so I didn't put a lot of thought into it.

[ian.byrne]

Thanks so much, so you remember I mentioned Swiss cheese, well this is one
such hole:

I understand that I need to upload the f3d file into my data panel and then
insert into new sketch, however there is then nothing on the timeline apart
from the fact that I've imported the model. After a quick skim I can't seem
to find an answer but will keep looking.

Look forward to watching the screencast, and thanks again for helping me
fill the holes!

All the best,

Ian

[Oceanconcepts]

If you want to view the timeline you will need to just open the file you put into your data panel directly. Then you can follow the steps used to create the model. Inserting it as a new component leaves all of the timeline in the original file. 

[ian.byrne]

Great, many thanks indeed! Obvious once you know how..

[chrisplyler]

Of course you'll want to start another Component. You'll want to start a Sketch on a plane such that a profile can be Revolved around to create the nut. In that sketch you'll want Project>Intersect some of the existing geometry and use Offset from there to get an appropriate interior face for the nut. Something like this perhaps...

[ian.byrne]

Thanks for all the input so far, I've not had a chance to try everything out but the project and offset options are beginning to make sense...