In Drawings, how to display different dimensions in either SAE or Metric

[agareau]

In "dimensioning" a part in "Drawings", that is made up of North American sized material (SAE) but has many features that are Metric, such as 3mm hole, metric fasteners; I wish to dimension the holes in Metric (mm) and the material dimensions, length width, in SAE (in).

[Drewpan]

Hi,

Is this a Drawing Exercise or do you plan to actually fabricate your design?

I am just wondering why you might want to do this. If you have access to Imperial OR Metric you would

typically pick one or the other. Mixing measurements and dimensions in one design is the sort of thing

that causes problems when people have to convert those units. NASA managed to create a new crater

on Mars after a Joint Project with the EU when they accidentally calculated for pounds when it should have

been kilograms. Gimli in Canada had an unexpected visitor when a 767 ran out of fuel when the refueler

made a similar miscalculation.

I cannot think of an actual reason you might measure in feet and inches and use metric screws or vice versa.

Unless it is some kind of re-cycling project and you have been supplied with both. Even then I would try to

stick with a single measurement system.

Just wondering.

Andrew

[agareau]

This a matter of practicality: which is easier; finding a 4mm drill or trying to find a .15748" drill ? OR asking your local steel suppy store for some 1-1/4" angle aluminum OR some 31.75mm angle aluminum ?

Andre

[Drewpan]

Hi,

I agree with practicality but most tolerances needed with hardware like nuts and bolts isn't that tight. Just pick

one and stick with it if you have both available. If its about which drill is easier to find most designers I know of

would simply design the hole to a Standard size unless there is a very good reason not to. The sort of Project

where you need ultra precision does exist but you are probably using much more precision tools than a normal

drill and probably making the actual hardware also. Drilling Angle stock doesn't sound too precision to me. If you

really need to go to 5 decimal places then you wouldn't be worried about a 4mm drill.

I understand that there are two common systems of Standards but as I said, mixing those Standards when you

don't have to is a BAD idea. I'd suggest redesigning the Project so that it uses ONE Standard (unless it is critical

like for Brain Surgery or Nuclear Weapons) and even then I would be very careful if I did mix things.

Good Luck with your Project.

Andrew

[HughesTooling]

@agareau  I guess the problem is with holes callouts? You can change dimensions between inch and metric. Only workaround I can think of would be to create the drawing in mm so hole callouts are in mm then edit dimensions and change to inches where necessary.

@ClintBrown3D  Are there going to be any options for editing hole callouts? The fixed precision is not that helpful and any way to change units?

Thanks Mark

[agareau]

This is not fprecision work and yes, that is exactly what I'm trying to do...use standard equipment and supplies.

A standard 5mm is very common BUT a .19685" or if you prefer, .197" drill is not. 

Likewise, a 1-1/4" angle aluminum is commonly available BUT a 31.75mm angle aluminum is NOT.

[agareau]

I'm a very infrequent user of Fusion 360 and posted my question in case there was a hidden command or devioous method of changing the "Dimension" units, "on-the-fly" per individual feature in the drawing to make "life" easier for the person making use of the drawing. Living in North America, especially in Canada, having to deal with both units of measure is a reality. If there isn't, then maybe a suggestion to the Fusion 360 people would be to implement such a feature.?.? I can't believe that I am the only person that is using some very inexpensive items from China and trying to adapt them to North American supplies, such as aluminum, steel, wood, etc.

Andre

[HughesTooling · Accepted solution]

I thought there was a way to edited several dimensions at once but now I try it doesn't seem like you can! More lacking functionality. Even if working in different units is frowned on there are plenty of times where you want different precision (decimal places), you'd think you could change several dimensions at once. Or better still change precision\units before adding dimensions (presets).

Fortunately for me I'm a one man band and don't need drawing often, if I did I'd probably be using a different program!

[ClintBrown3D · Accepted solution]

Hi @agareau 

I'd love to hear from you directly, and to get your thoughts around this. If you're up for it, here is a link to my calendar, please book a 30-minute session with me, and we can chat on Zoom (Note that times are in 24:00 format so 03:00 is 3am, 15:00 is 3pm). 

Drawings can be created with dual units (we added this in September 2021). In the document settings, you can set up Alternate unit display. 

This results in something similar to what you see below:

Holes are generally created to a standard, for instance metric M, or BSP tapered. See image below, in a metric mm part, I have an inch BSP tapered threaded hole and a threaded Metric M profile hole.

These hole designations are then shown on the drawing, as laid out below:

@HughesTooling as an FYI, I'm gathering requests for more granularity on hole notes. Each request (meetings, emails, forum posts etc.) gets collected and categorised in my PM backlog. This information is used to prioritise the features that we build.

[HughesTooling]

Tried the above suggestion but doesn't seem to work for the tap drill size or hole and counterbore sizes. Would be nice if at least the tap drill size was used (5.1mm).