Joints not working on a hinged part

[Anonymous]

Hello everyone!

This is my first time posting here. I have a issue where the joints don't work as expected.

Currently I have 2 grounded components that the 2 telescoping tubes and hinge piece connect to.

The frame is linked to the hinge piece and telescopc tubes.

However fusion isn't working when I apply joints to them all.

i.e:

-Revolution between the grounded hinge holder and hinge piece

-Rigid between hinge piece and frame

-slide between the 2 tube pieces

-revolve between lower tube piece and plate (hidden)

-revolve detween upper tube and frame

Anyone know what's going on?

[Brady_Fulton]

In your screenshot, is the upper arm assembly correct and the lower one is "breaking" when you rotate your hinge joint?

You can try to create an "as-built" joint for the sub assembly to hold all the components together, and then apply your hinge joint to that.

Hope this helps.

[Anonymous]

I've tried the "as is" joint between the 2 tubes only  without any other joins and I get a yellow error already.

Applying all the other joints as well breaks the whole thing again like what's already happened last time.

[beresfordromeo]

Are you able to share the model?

[Anonymous]

Here's the share link:

http://a360.co/2yAgc22

[beresfordromeo]

Apologies but I can't seem to download this model. Could you please check that Allow item to be downloaded  is turned on under Privacy Settings  in the Share Public Link window.

Great model by the way...

[Anonymous]

Thanks...it's not finished yet though and it's my first time really dealling with assemblies and joints in fusion. I've only been working using scuplt and on smaller parts for far.

I've changed the setting to allow downloads for now. It's really bothering me atm since I want to show the lid working.

[beresfordromeo]

OK I got the model thanks. 

Can you tell me about the rigid joint that I have supressed at around 1.20 in the video? What is this for?

[beresfordromeo]

OK ignore the question about the rigid joint. That was a silly question.

I have recorded a screencast for you. 

In short I deleted Slider 9 on the component Gas strut 2. I then shift selected 2 edges on each of the two gas strut halves (Gas strut lower 1 and Gas strut upper 1), used the align component command to align the two components then used an as built joint  between them to replace the slider component (now Slider 10).

I just wanted to point out also that I was able to get rid of all of the errors in the timeline of your file so you might be able to look at that if you get the chance. I didn't have time to really get to know the model to see if there were any adverse effects after doing this but I think it is all still there.

Good luck with your project.

[Anonymous]

Thank you so much for that! So it seems aligning the 2 components solves that!

However as soon as I try to repeat the same thing on the other side, the existing joints will break and the components rotate around the axis in a awkward way instead. Maybe it's something to do with the fact that I copied the gas strut parts early on?

Also, does the link to the file update so that it goes to the latest version?

[beresfordromeo]

Hi Excelray1

Yes, from the brief look that I took of this yesterday the gas struts and sub-components are copies of each other. The joint, Slider 10 is the same joint in both gas struts. I am not sure that Fusion has a way of making a copy/move component unique after creation. Hopefully someone will correct me about this.

Anyway the timeline means that this is not an real issue. You should be able to go back to the point at which you duplicated the gas strut and remove the copy/move command. Hopefully from there you can sort out your gas strut, get your joints in place for it to work and then use a mirror command to mirror the components. From there you can use an as built joint for the second gas strut.

Actually I apologise that I did not look more closely at this model. I will do this and post as soon as I can but you never know, you may get there first.

[TrippyLighting]

---

@beresfordromeo wrote:

I am not sure that Fusion has a way of making a copy/move component unique after creation. Hopefully someone will correct me about this.

---

With the timeline enabled, No, there is no way to make a copy of a component it's own independent version. It's a consideration the needs be made when you copy the component. If you use paste it will be and instance, an always identical copy of the originals. If you use paste-new it will be it's own independently editable component.

Only in direct modeling mode the option to make a copy component independent  exists.

[Anonymous]

Well ,so far I've deleted the copy-paste of the gas strut so only one is left.

The aligning isn't working for some reason.

I've tried deleting all other joints on the 2 components and it still produces the same result.

When I press align. the two components come together as intended but only for a split second before is turns funny (image on right).

I haven't found any other joints relating to the two components that might affect it.

It's only affecting the orignal sub assembly (gas strut 1) and not the copied version previously.

Weird.

Before:

After:

[beresfordromeo · Accepted solution]

OK firstly my sincere apologies. I really hate not having time to provide solutions properly and I wanted to get you going in a hurry so I think that I have wasted your time somewhat.

The reason for the original joint conflict I now realise is that there is a slight offset between the hole that you have in the lid and the hole that you have in the base part. In short you need to use a cylindrical joint as opposed to a revolute joint between the upper gas strut component and the lid.

The joint is breaking because the revolute joint wants to break the slider joint in order to make up for this offset.

As soon as I get the chance I will do a screencast for you. Apologies again for misleading you a bit.

[Anonymous]

Finally got it working!

Yeah the cyclindrical joints worked out.

Thanks you beresfordromeo for the help!

It kinda makes sense since a normal revolute joint would make it over constrained.

Here's it is in its full working glory:

[beresfordromeo]

Great news.

Thanks for the solution acceptance and many thanks too to @TrippyLighting for the very useful info and encouragement.