Help! - how to make nest my manufacturing model?

[r.moss]

This seems a really silly question but I've Googled it and cannot find a demonstration anywhere.

What I'm trying to do is make a laser cutting pattern for some sheet metal.  I want to change the original dimensions slightly as parts will be machined after cutting.  

I started by going into the manufacture workspace and saving an empty file.

In Component Sources, I imported two models.  I created a manufacturing model for these 2 models.

I then added a third model via Component Sources.  There didn't seem any way of including this in the first manufacturing model, so I created a second manufacturing model.

I then did "Generate Nest Study".  This seems to have nested the original imported components, not the altered components in Manufacturing Models 1 & 2.  (Under "Manufacturing Models" I have three items: Nesting Study 1, Manufacturing Model 1, Manufacturing Model 2).  The nesting study is not "below" the manufacturing models.

The file is here: https://a360.co/3KJf4gm

• How do I get F360 to nest the edited manufacturing models rather than the original component sources?
• How then do I get it to nest the whole set of manufacturing models as 1 set of nests (i.e. not nesting the manufacturing models individually)?
• How can I get multiple copies of some items without importing two copies at the start?  I know I can over-ride the nesting quantity in Component Sources but that is very tedious.  Suppose one imported model has 10 items as 1-off and 20 as 3-off, is there some way of turning these all into 2-off & 6-off via a single edit without editing each item in turn?  [And other imported models remain as 1-off so I cannot use the multiple copy field in Nest Preparation].

Thanks

Roger

[r.moss]

I've been looking through the help:

https://help.autodesk.com/view/fusion360/ENU/?guid=MFG-MANUFACTURING-MODEL-EDIT

and there is no mention of nesting a manufacturing model, so I presume manufacturing models only relate to turning, milling etc and not to nesting. Is that right?

[jeff.pek]

Hi -

There's a couple things you can do:

1) You can use the Arrange command in the Edit Manufacturing Model environment to nest your components.

2) If you have the Nesting & Fabrication extension, you can create a Nest Study (on the Fabrication tab), and it will nest selected components onto one or more sheets, each of which would become a Manufacturing Model.

Jeff

[r.moss]

Experimenting a bit more, once I have generated a nest if I right-click on one of the nests I get an option "Edit manufacturing model". Aha!
I can then (for instance) press-pull one of the outer profiles to make it larger. It starts to overlap its neighbours in the nest. I close the manufacturing edit. The nest does not indicate that it is out of date!

If I then generate the nest again, it does not reposition the items to match the new outer diameter. Instead it loses the press-pull change and reverts to the original geometry.

So editing the manufacturing model doesn't accomplish what I want.

[jeff.pek]

Right, it won't support that. The manufacturing models created via a nest study will not be regenerated after a manual change to the mfg model.

What you would want is to change the source component, which should invalidate the nest results, and then when you re-nest, you'll get new mfg model(s) reflecting the changed component(s).

Or, if you have an already existing manufacturing model, you can use Arrange to do a "local nest" in the context of that mfg model.

Jeff

[r.moss]

Ah! So each nest is actually a manufacturing model! Yes, trying that I find I can right-click on a nest an select "Edit manufacturing model".

[r.moss]

Hi Jeff

Thank you.  Dare I say it, this is a feature which could do with improvement.   I have 139 laser-cut parts.  Perhaps 20-30 of them have bores or OD that will later be machined to a precise dimension.  I would like the automatically generated dimensions on the drawings to be the final finished size and I want some way of making the laser-cutting patterns undersize, to leave room for machining.  I also need to get rid of about 100 drilled holes and square-off the beveled edges.

I tried editing the manufacturing model.  Yes, I can use push-pull etc to add some material to the bores.    The trouble is, this isn't a permanent change.  As soon as I make the slightest change in the original model space and update the nesting model, the manufacturing model changes are discarded.   For instance, I can change the visibility of a sketch in one file (not the one I've edited in the manufacturing model).   This is recognised as a change and any push-pull I've done in the manufacturing space gets lost.

Ideally each model file would have its own manufacturing model (in the same way it has a linked drawing) and that would be imported to the nesting process.

Best wishes

Roger

[jeff.pek]

Hi again -- thanks for the detail.

You can do that, you just do it upstream of the nesting. If you have a "manufacturing model" -- i.e., a model that has been adjusted to reflect the as-manufactured state -- then you can have that be the input to the nests, and then the nested components are as you desire them.

I hope that I'm understanding what you're trying to do.

Jeff

[r.moss]

Hi Jeff

Yes, I want to have a manufacturing model that takes parts from the model workspace, applies a simple change (reducing the bore by 1mm, getting rid of holes) and then nests it.  I want this to be "robust" in the sense that I can make a small change to the original model (e.g. changing sheet thickness) and the manufacturing edits will update automatically.

This doesn't seem to work.   I was pleased to find that each nest is a manufacturing model and I could edit it to remove holes etc (push-pull to fill them).  I wasn't able to change the external dimensions as parts would overlap, but it's a start - or so it seemed.  If I edit the manufacturing model though, the nest is regenerated and all the edits are forgotten.   So one has to be ever so careful to turn off "Automatically calculate nest" and never to change the original geometry and have to re-nest it.  In fact "Automatically calculate nest" turns itself back and I keep finding F360 is unresponsive for a few minutes while it re-nests.  Not helpful when I'm waiting to make a further change!  It also seems to re-nest for the most trivial of changes (e.g. changing sketch visibility) - totally unnecessary - and I get the impression it is regenerating every sheet when I have only changed a component on 1 thickness of sheet.

I don't find it at all user-friendly.  Either I am missing something very basic in terms of work-flow or it needs a lot of UI development.

Anyway, it's now 8 pm.  I was up early and I have spent the entire day lovingly eradicating holes, tweaking dimensions of bores that will later be machined etc.    Not helped by finding that Component Sources had somehow got confused about the number of items required and given me too many of one and not enough of another [this would be more obvious if the sources tree didn't expand over about 30 scrolling pages - there is no way of only showing the non-ignored items].  So yesterday I drove hundreds of miles to pick up the metal and now I find I've got the wrong size.  Fortunately I have managed to re-position things onto different thickness material so I can cut the bits I need but I could do without the hassle.

At the end of the day I have exported 15 DXF files for the different thickness sheets.  The files contain about 90 different shapes and 2-8 copies of each.  Marvellous.

I then switched to a computer with a 2D CAD program and opened one of the DXF files.  ARRGHHH!  None of the manufacturing edits have been included in the export.  So the cutting pattern in F360 looks like this:

(the smaller flanges have bolt holes removed and bore reduced for machining after laser-cutting) but the DXF file looks like this:

The holes are there!  And the bore is the original diameter!  That's a whole day of my life I won't get back again and I can ill afford to lose the time on an exceedingly urgent job.

I'm not sure what the point of the manufacturing model is, if one cannot export what's visible on screen.    I cannot be the first person with problems like this.

I really do not want to have to "fork" a complete set of models and change their dimensions just for the nesting.  I would prefer to have a model that can be edited periodlcally and relates to both the 2D drafting and the laser-cutting nests.    I suppose I will have to "corrupt" all my model files with the cutting rather than machining dimensions, generate a new nest, save the DXF files, then roll back to earlier versions of the model files for the 2D drafting.  This isn't an efficient way of working....if I need to change the design I will have to mirror the changes in both the machining and the cutting versions.   [While I'm on the subject, the 2D drafting has its own hassles.  Any trivial change like opening a model sketch triggers a new version "*".   If I save the model file, the drawing updates and many of the sheets are greyed out until I click on them to refresh.  All very time consuming when the parts have not been edited at all].

Roger.

PS.  Ideally one would make these changes to a manufacturing model in the original design file.  One could envisage multiple manufacturing models, one for laser cutting, one for rough machining, one for grinding etc.  One should then be able to pick which of these variants is used for nest preparation, which for making 2D dimensioned drawings etc.  Currently I can make a manufacturing model in each part file but there is no way of nesting this so it doesn't seem to be much use.