Autodesk Inventor

[#1]

I have an assembly that is made up of 3 unique parts ( 5 parts total). These parts and there features are to be laser cut, then assembled and welded along the outer perimeter in the small chamfer. I have designed the parts to have 5/16 holes, which will be later tapped to 3/8"-16 UNC after assembly.

Once these parts are assembled, I don't understand how I can change the holes to reflect this. Meaning I want the parts to be pre-drilled(laser cut) with 5/16 holes, but I want the assembly to then have 3/8-16UNC holes.

The hole command will not let me select the existing hole features in the assembly and add threads. What is the consequence of inserting a 'new' hole with 3/8-16UNC threads over the existing 5/16" holes in the assembly?

Is my workflow incorrect? should I have the parts modeled with the tapped holes and just make a note on the drawing to not tap these holes until assembly? how does that affect the laser cutting?

Thanks

Sean Farr

Inventor Pro 2013

[#2]

I can't attach .zip files that were created by windows ( right click, send to compressed .zip folder), gives me an error stating something about extension does not match binary..blah.blah.blah!!

previous post had part files, here is the assembly file,

any ideas of how to approach this??

Thanks

Sean Farr

[#3]

IV doesn't like your 5/16 holes. The minor dia for the 3/8-16 is smaller than 5/16, so IV thinks it has no material to remove.

You might be able to edit thread.xls, don't know.

Or, change the drill size to something smaller in the ipt's.

[#4]

So you are adding holes (threaded) over top the existing holes in the assembly? I thought there used to be an option to just thread existing holes, for a case like this? Not create new holes...

If I change the holes in the parts, then the drawings will be affected and the wrong sizes will be cut out. 

I think my best work around it to not have threads in the final assembly, their only benefit of existence that I can see (for my case) is the ease of calling them out in a drawing.

I have attached a drawing (not finished) of what I could probably do to bypass this issue. Edit the hole note to something like that??

Any other ideas are welcome, as I don't see this as solved.

thanks

Sean Farr

[#5]

Would it not be easier just to produce  the assembly drawing as normal then un-check the show threads option, this way you can then, from one file, produce two distinctively different assembly drawings or by the crafty use of layers settings, just as in AutoCAD, you can then switch on/off any hole/tread notes etc.

With the tapping hole, this seems to be an Inventor thing, I've noticed that when using some of the threads Inventor takes the tapping hole to the "nearest common available drill" even with the precision set to 1/128inch, for you r chosen thread, I can't get inventor to display below 5/16 tapping drill for this hole, when the best tapping hole will be 8mm (0.314 inch) but this can be simply worked around by editing the hole/thread text.

[#6]

I think my last post, just before yours, is the same idea, edit the hole note to reflect the needed thread info. The hole size currently is 5/16 which the drill size for tapping 3/8-16UNC. These holes will be cut out using a laser cutter.

I will use an assembly drawing, the example I posted above, to ensure that the holes get tapped to once assembled. 

Thanks

Sean

[#7]

I do similar work all the time.  I simply create my drawings to reflect final outcome: Example 3/8" tapped hole.  I then go into my flat pattern and edit it to show 5/16" holes instead.  This way my g-code for my plasma will be right and the final drawing is right.

Would that work for you?

Rob

[#8]

Not sure I follow, so you create your part WITH the tapped 3/8? holes, then edit your flat pattern to show 5/16" holes?

Do you have an example?

I don't know how laser cutting works, whether the actual size of the hole is relevent or does the laser cutter read the parameters(dimensioning)??

Thanks

Sean

[#9]

I don't like shortcuts like editing the hole note but that is a quick and simple solution I have used.

Another option we use with weldments is creating a derived part from the assembly. This would allow you to edit the part like any other .ipt file.

[#10]

So using your worklfow:

1. Create all parts ( with drill hole size and not tapped hole size)
2. Assemble parts
3. create a derived part from this assembly
4. edit that derived part to reflect tapped hole size.

Some key points, the individual parts NEED to have the correct drill hole size, for production. There is an inventor issue in the assembly level, that it won't let me create a new hole over top the existing holes. If i create this derived part, will it allow me to edit those existing holes or make 3/8-16UNC holes over top of them? or will i have the same error as I do at the assembly level?

I am not sure if what I am doing is incorrect? the more i think about this, the more i feel it is an inventor issue.

This particular assembly requires the holes to be pre-cut by the laser cutting machine, then assembled/aligned and tapped by a worker.

Why can't I make this happen with inventor?

Thanks

Sean