Joint to create a truncated icosahedron

[canoe]

Group

I hope this is in the correct spot. I want to create a truncated icosahedron e.g. a soccer ball. The work flow I am using is to create a hexagon part and a pentagon part then create an assembly of one section which is four hexagons and three pentagons. Then create another assembly of the first assembly as a sub and fill in the extra holes with the needed shaped parts.

I am used to using Solid Edge assembly environment and I do however understand all software packages do things a little differently. In that environment I usually need three joints or assembly constraints to have a part that is fully constrained in the assembly. In Fusion as far as I can tell I only need one joint which for most cases is a great time saver. But sometimes I find myself needing more than one as in the case of the attached photo. I have inserted the first hexagon and grounded it then added three more using a revolute joint along every other edge of the hexagon. Then I add three pentagons in the same fashion. I realize I can just simply grab each one of these petals - if you will - and move them which is a great feature. If I grab the petals and move them I can get them close but not perfect and any error in alignment will just be compounded in the main assembly. But here comes the question. Can I have a second joint that constrains the vertices either collinear or by the end points of the adjacent hexagon to pentagon?

Sub-assembly.

[canoe]

It is not exact but close enough to make the project I want to make as it supports no weight. It will be made from 1/4" finish plywood glued with tightbond glue. It still would be nice to come up with a solution since I have ran across this several times.

[laughingcreek · Accepted solution]

Something like this?

[lichtzeichenanlage]

@laughingcreek Holy s**t... You can join components without an body! Didn't knew that. 

EDIT: Name added

[laughingcreek]

@lichtzeichenanlage-you don't need a sketch either.  sometimes when creating a component in place, i'll start by jointing the origin point of an empty component to where ever it's going. (only works if you have a logical place to joint of course, such as a bolt hole etc.)  I like having my origin point in a logical place in my component, and this work flow lets me do that from the beginning, instead of moving it later, which is a pain.

[TrippyLighting]

Yes, grounding, rigid joint, rigid group and as-built rigid all work with the component origin only.

[canoe]

Awesome thank you! I think I just did not tinker around enough. So if I am understanding the video the hexagon will not pop into position until you add the third revolute. Interesting. I will go immediately and try it out. BRB!

[canoe]

Worked perfectly I swear I tried this when I posted but maybe something else was going on with the file, parts, etc.. probably just me. Thank you so much for helping me out. I am impressed with Fusions ability to just grab a part and move it and the joint still does not violate e.g. the revolute. I thought if the software is robust enough to do that this should NOT be a problem for it to handle. Turns out it is not.

[mark33.in.oz]

Thanks very much for that video.

Sound would help so you could explain what you are doing rather than trying to watch what keys are being pressed while watching what you are doing.

Bit confusing.

But it is good.

Work to be done on making one myself.

[mark33.in.oz]

May I also put my hand up and ask for a bit of help on how to do that?

Though I can watch the video, I think I am missing some crucial parts to what is going on.

I don't get the dotted line that extends past the hexa/penta-gone.

[laughingcreek]

I can flesh this out for you a bit latter tonight.  This video was just a quick response to the original OP.  I suspected he just needed a visual on how to apply an extra joint to get what he was doing working.

The dotted line ended up serving no purpose, was just left over from the original sketch.

In the mean time, this approach relies on using components and joints, so you may want to read up on those. 

[TrippyLighting]

The problem with this approach is that is it very easy to over constrain the system when assembling/joining these pieces using too many joints.

[mark33.in.oz]

(Gee this forum setup is a bit confusing when replying to posts)

Thanks very much.

I am now posting another question but.......

Your help is appreciated.

[mark33.in.oz]

In the mean time I have watched the clip and started.

All good until I start to join the first hexagon side to the second hexagon side.

In your clip, when they join, the shapes go a bit crazy and rotate around the joining axis.

Mine don't.

If I could work out how to capture the clips myself, I would show you.

Shall go away and try to get that under my belt to help with future help requests.

[TrippyLighting]

I though I provide a link into this thread to this thread where a user has created all Platonic solids in one file for everyone to use.

[mark33.in.oz]

I am getting most of the (your) clip now on how to make one of these things.  (Not going to spell it, as I don't know the spelling and don't want to spell it wrong.)

So, I get how you JOIN the first two sides together.

You join all the hexagons to the bottom pentagon.  Fair enough.

Then you join the hexagons together.   Again:  fair enough.

But I would have added the first and second hexagon then joined them together.

So jumping forward in your clip:  you start to join the hexagons.

You JOIN, then select one of the hexagon's sides.  You then select the adjacent hexagon's side to which it is to be joined.

The OBJECT starts doing its "dance" as it twirls around.   "Behind the scenes" I notice you press the RMB and drag the mouse.

This seems to join the two sides.   If I don't do that:  the sides are not joined.

Dumb question:   how does that work?

Also in your video the COMPONENTS have a better definition than on mine.   Probably just a setting, but I'm just wanting to check.

[TrippyLighting]

@mark33.in.oz I am assuming you are replying to @laughingcreek ?

[mark33.in.oz]

TrippyLighting,

Sorry.  You are correct.   Again:  new to forum and not quite got the structure of how to do all the fancy stuff.

[TrippyLighting]

In case a user uses the forum search I post this her as well: