draft analysis: trivial increase of max angle would enable overhang analysis

[gregmainland]

In 3D printing you have to add supports to overhangs, or in general to any part of a body which has a too-shallow angle. I would like to be able to visualize these too-shallow angles when designing a body to print. Autodesk Meshmixer has an "analyze overhangs" feature which highlights regions that will need supports because they are shallow angles:

meshmixer overhang analysis

I would like to be able to do this analysis directly inside Fusion 360 because in a sculpture like this one, there is quite a lot of tweaking required to update the sculpture, and exporting repeatedly to meshmixer to see the violations is quite slow.

Fusion 360 already has a draft analysis feature:

fusion 360 draft analysis

This already does *exactly* the right analysis, but it is *unusable* for overhang analysis because the maximum draft angle you can set is +/-15 degrees. If you were to increase that limit to +/-90 degrees, you'd be unlocking overhang analysis for additive manufacturing. It seems like an easy win because it's a trivial change for basically a whole new feature.

(The only reference I could find on this topic is on the archived ideastation https://forums.autodesk.com/t5/fusion-360-ideastation/increase-draft-angle-range-in-draft-analysis-t... but thought it was worth reviving the conversation here. It seems like such an artificial restriction that it might be considered a bug.)

[gregmainland]

I just found two more requests for [basically] this:

https://forums.autodesk.com/t5/fusion-360-ideastation/multiple-draft-angles-color-coded-in-analysis-...

https://forums.autodesk.com/t5/fusion-360-ideastation/undercut-analysis/idi-p/5187981

[MoshiurRashid]

Hi @gregmainland 

Good thinking and a very nice suggestion. It was taken under consideration back in 2015.

But, DRAFT ANALYSIS is not the tool that will help you in this case. Draft analysis is designed for Mold Making. It is the angle measured from vertical axis of the Direction of pull (the direction of which core and cavity will go up or down)

It just shows you if you have any mixed up core, cavity area or required draft area (Click here to see my screencast on draft analysis)

[gregmainland]

Hi Moshiur, thanks for responding. I watched your screencast, but I still think that this analysis just tells you the angle relative to an axis of your choice. I think you are saying that it will be more complicated because it also shows shadowing of different parts, is that right? I ran a quick test with one body made of three balls, and it doesn't seem to do any shadowing, it looks like it's pretty much just the relative angle to the axis. Did I misunderstand you?

[MoshiurRashid]

Yes, I agree. In one sense you can use it for overhang measurement by trial and error method. Good for a quick check.

[hyleanlegend]

This is still an issue, over a year and a half later.  Not only is it a trivial change, the draft analysis tool shouldn't have arbitrary limits anyway, since users are the ones determining their manufacturing needs.

[Bryan.Hook]

Got here through googling this issue...As a mold maker using Powermill and Powermill modelling (stripped out Powershape) I would very much like more than 15 degrees of draft analysis, please.