I need help shelling a part!!!

[MKR]

Alright folks, I have been using Autocad LT 2012 to draw parts for a while now and have recently had the need to draw a few parts in 3d. I purchased an educational version of inventor and I am having a few issues. My main issue is I drew the top profile of my part, extruded it, and then split the part to achieve the side profile. That is where I am stuck. I am trying to build this part with 4 sides out of .125" plate with a square corner seam of .0625" on every edge. After my split I try to shell out my part to .125" wall thickness and I receive an error that states "it would remove all walls from my part."

 

Where do I go from here? I have been reading forums, searching, and trying everything I could think of and I am stuck.

3d framerail.ipt

[Bishop]

 

 

I'm sorry, but I have no idea WTF I'm looking at here. Did something get corrupted or is this actually what you're working on? (Sorry about the small size - my laptop screen is quite small, so any bigger than that and I can't see everything.)

 

1. Why are you trying to use sheet metal here?

 

2. Your sketches are remarkably unconstrained here. Sketch 1, for instance, is missing 49 dimensions / constraints. This is not a good way to start off a model. (Gawd, I can't believe I'm actually saying that ... I sound like JD now!)

 

3. Pretend the "Move Face" tool doesn't exist. No, really - I mean it. If you need to use that tool, then you didn't plan ahead well enough and you should probably start over and chalk the wasted time up to a learning experience. I'm not being sarcastic at all.

 

4. What are sketches 3, 8, 9, 10, & 12 doing? They're just random points in space?

 

 

Those are just the questions I can come up with right now. At this point I'm pretty confused about what it is exactly you're trying to make. Can you clarify a little? I'm not trying to be a jerk here, I really don't know what's going on in this part and need some more info.

 

In the meantime, check out some of JD Mather's tutorials, and work through the tutorials that ship with Inventor.

[MKR]

Thanks for replying.

 

You are looking at a frame rail for a car... and therefore I am trying to produce this out of 11 gauge cold roll steel.

 

Yeah, after reading multiple forums and reading JD I am waiting for his input. That's going to be harsh! The dimensions should all be there right? My original drawings for the top/bottom profile and side profiles were imported from Autocad. I had to dimension every portion of those drawings.

 

I have tried using the "move face" tool without luck, so yeah, I am out on that.

 

The other drawings you are referring to aren't important. The 3d part is all that is important in the drawing.

 

Basically I drew the profiles of the frame rails I needed in autocad and have been designing a few parts to fit. In order to get flat drawings to have laser cut I needed to take my profile/2d drawings and convert them to 3d. Doing that would allow me to separate the 3d drawing into 4 pieces (top, bottom, side, and side,) and then flatten them out. Once I have them in a flat; save them in a .dxf file and have laser cut. Trying to get the flat patterns from the 2d drawings would take a lot of time in comparison (assuming I knew how to properly draw in inventor) to doing this portion in inventor.

[Bishop]

So, will all 4 sides of the frame rail be separate pieces which are independently laser cut & bent, then welded together? Or are you looking for a single piece which will be laser cut then folded and welded along a single seam? Or is this a just a single seamless piece that's formed through another process?

 

What version of Inventor do you have? I've only got 2013 at home, but I've got 2011 and 2013 at work. If 2013 will work for you, I'll scribble something up really quick that you can maybe follow along with to do what you need.

 

It's not a great idea to do your sketches with AutoCAD. It's a ridiculous amount of extra work that you just don't need to go through. Inventor is not AutoCAD. When using it, forget every paradigm that you ever learned with AutoCAD.

[MKR]

Yes, it will be 4 independent sides that will be laser cut, formed, and then welded together. My version of inventor is 2012, I would assume they will all transfer in though, right?

 

So you are saying I would be better off doing the exact same sketch I did in autocad, in inventor? Would that be the best way and then import to autocad after the fact? Yeah, going from one autodesk product to another, I felt like they would mesh together rather easily.

[JD Mather]

Yeah, going from one autodesk product to another, I felt like they would mesh together rather easily.

 

There is nothing fundamentally wrong with using AutoCAD geometry in Inventor, if it is good. The evidence (form the file) indicates that your AutoCAD geometry is garbage - that you don't know how to use AutoCAD either. You should not have lines overtop of lines (I didn't even bother to lool any further, but if I did I am confident based on years of experience that I would find multiple things done incorrectly in AutCAD.)

 

Start here http://home.pct.edu/~jmather/skillsusa%20university.pdf

 

Concentrate on one line at a time - posting your file here often.

Forget forget forget Move Face - a beginner should never ever us Move Face (I have used it maybe twice.) There is almost always a better way. I doubt you should be using Split.

I doubt you should be using Sheet Metal tools, but it isn't really clear to me what your design intent is. Can you post picture or url to similar real world part?

[JD Mather]

...better off doing the exact same sketch I did in autocad, in inventor? .

 

No - it was done wrong in AutoCAD.

Do it right in Inventor. (or if you must, do it right in AutoCAD).

[JD Mather]

I don't think these dimensions would make logical sense in any CAD program. In any case, they are not inspectable and not manufacturable.

[JD Mather]

I purchased an educational version of inventor......

 

Any student 11 years old or older anywhere in the world can get Autodesk Inventor (and other Autodesk products) for FREE student learning license here http://www.autodesk.com/edcomunity

[Bishop]

Yes, it will be 4 independent sides that will be laser cut, formed, and then welded together. My version of inventor is 2012, I would assume they will all transfer in though, right?

 

So you are saying I would be better off doing the exact same sketch I did in autocad, in inventor? Would that be the best way and then import to autocad after the fact? Yeah, going from one autodesk product to another, I felt like they would mesh together rather easily.

 

 

 

Autodesk products don't always work and play together very well unless you really know what you're doing. I don't use AutoCAD, so I can't really speak to getting your work back over there.

 

As far as transferring files between different versions of Inventor ... you can go backward, but not forward. My 2013 can open 2012 documents, but not vice-versa. If I open a 2012 file and save it again, it can no longer be opened by 2012. Same goes for all versions of Inventor. You can open documents from an earlier version, but the earlier version can't open the later documents.

 

The part that I've attached here shows one way to do one of the independent sides that you're looking for. The dimensions and such are not in any way rational - all I did was click in a bunch of places to make a squiggly line - but the technique is solid and relatively clean and easy to follow if you take the .IPT apart and look at how I did it. Do this (or something similar) 4 times with matching curves on all the parts, and you'll have what you need.

 

 

Anyway, here's the file for you to look at and dissect: Part1.ipt

[MKR]

JD - Thanks for helping. I went back into autocad and found only one overlapping line and corrected that. I am not touching the move face tool at all.... I am sure you are right with split tool; certainly that isn't the right way to do what I am trying to do, but the only way I could figure out how to get the profile.

 

After starting a new drawing I imported in the side profile of the frame into inventor and used the add automatic dimensions and constraints tool to add all that to the drawing. After that I created a face and extruded that to .125". Is this what yall are referring to? Now I need to import my "proper" top profile drawing?

 

Bishop - Thanks for adding the drawing for me to study.

3d framerail side 1.ipt

[JD Mather]

Never never ever use the Autodimension tool.

How long would you have a job if you sent this to the shop floor?

 

Forget AutoCAD. (this would work, but you would need too much training to get there as your AutoCAD is no good either)

Read that document I linked earlier.

Draw one line and attach the file here.

[MKR]

Okay... I thought you wanted every possible dimension; so now we only need the ones necessary to recreate the part?.?.?.Autocad is pretty basic; you input dimensions that you would like (in my case,) what I would like my part to resemble. That is exactly what I have done. Sure, there is a ton more to the program, but it is still rather basic.

A line.ipt

[JD Mather]

I am quite familiar with creating accurate geometry in AutoCAD. Your (AutoCAD) geometry appears to be garbage to me. (I could be wrong about the AutoCAD geometry - attach the dwg here.)

 

You must have missed some of the instructions here http://home.pct.edu/~jmather/SkillsUSA%20University.pdf

 

Have you ever created anything out on the shop floor? On a Bridgeport or other milling machine or on a lathe?

What is the first thing you do to control geoemetry?

Establish zero points (Datum).

 

Your line is not constrained to the Origin CenterPoint.

At first this will seem like extra work - but as you learn Inventor you will see that there is no extra work, in fact it reduces work. You could have clicked on the origin to begin with. Since you missed it when creating the line, simply drag the endpoint of the line to the origin. You will see it snap green.

 

Notice that the line changes color when you drag the endpoint to the origin and in the lower right corner it now says Fully Constrained.

 

Now draw the next line and attach here.

Edited October 19, 2012 by JD Mather

[JD Mather]

This document might be more informative that the previous link I posted (that was for a shortened presentation)

http://home.pct.edu/~jmather/AU2007/MA105-1L%20Mather.pdf

[MKR]

JD, I have attached a side profile drawing of what I am doing that was done in autocad lt 2012. Garbage or not, it works for me.

 

The new tutorial you sent is a lot more informative than the shortened version and I think I can gain from it heavily.

 

I have attached a photo of my bridgeports and my delta lathe, so yes, I have. I have a 15,000 sq. ft. fabrication facility in which I fabricate all kinds of metal pieces daily... I can build just about anything. I have always paid someone to convert my 2d info into 3d and do what I am trying to do here. I am trying to learn how to do this to advance my abilities and ease with technology.

 

In autocad you draw in space...sort of. I always draw in the upper right hand corner of the "x,y" lines, and so naturally I went straight into inventor doing the same. After editing my line and moving it to the origin center and seeing it change to fully constrained I'm getting it. That makes complete sense.

side profile.dwg

[JD Mather]

In autocad you draw in space...sort of. ... After editing my line and moving it to the origin center and seeing it change to fully constrained I'm getting it. That makes complete sense.

 

Glad to see you didn't simply get mad at my direct style of addressing problems and flame out.

Inventor can be set up to "fix" your AutoCAD geometry on import, so I thought maybe it was altering your geometry.

But when I dimension your AutoCAD geometry almost none of the dimensions make logical sense to me - dimensions I can manufacture and inspect out on the shop floor.

 

Note that one of the two "horizontal" lines are not horizontal. There is a very slight angle. This should not happen in AutoCAD or any CAD program.

 

 

and these two lines are neither horizontal or parallel. I would at least expect them to be parallel?

 

 

I am a machinist - spent many years out on the shop floor before entering my current profession.

I set up design of parts in Inventor just like I was out on the shop floor making real parts.

Once you get your Sketch1 completed I can show you how I would make a master and derive the individual parts.

[MKR]

Alright JD, I have attached a file I think you MAY be happy with...we'll see.

 

As far as your direct approach goes, I can appreciate it, but it isn't very inviting. You have me in a position where I would like to learn, so I can eat a little crow if I can gain from it, and from what I can tell you are pretty much the master on all of the CAD forums. So, if I'm not on the right page I need to know it.

 

I think you know what I am ultimately trying to make here, correct? side rail 1.ipt

[JD Mather]

Exit sketch mode (if you are in sketch).

Right click on Sketch1 in the browser and then left click on Dimension Visibility.

[JD Mather]

zoom in here

What do you see?