Creating flat drawing of tube

[Anonymous]

Hi everyone,

We recently purchased a 4 axis plasma table. We are hoping to be able to cope the ends of tubes utilizing the 4th axis. The CAM program supplied with the machine wants a flat drawing (which it will then wrap around the tube) of what will be cut. 

My first thought was to convert the tube to sheet metal and then create a flat pattern or unfold it. But every time I convert to sheet metal it converts the end face of the tube, not the surface around the tube. The picture below is a very basic cope on the end of a 1 inch tube. The highlighted face is what it always ends up converting rather than the entire outside of the tube. 

[kelly.young]

Hello @Anonymous I see that you are visiting as a new member to the Inventor Forum.
Welcome to the Autodesk Community!

It sounds like you want the outside edge of the coped tube for the flat pattern.

In the Flat Pattern Environment you can RMB on the flat face and Export Face As... to generate a .dxf file for use with the plasma.

Depending on what it imports this might need post processing.

Hope that helps!

Please select the Accept as Solution button if a post solves your issue or answers your question.

[Anonymous]

WOW! That screencast thing is amazing! That video is very helpful! 

Looks like the rib might take a little bit out of the profile, but I am sure that I will find an easy fix for that. Most likely choose a spot on the end that is flat and just manually redraw the line. That is, if the kerf of the plasma cutter doesn't just cut there anyway. 

[kelly.young]

@Anonymous yeah, that was the part that I didn't know, how the plasma reads the line data and where it goes.

You can download the screencast, it's free.

It also works for any program so you can switch between windows and whatever program is active it will record.

I would assume that the outside edge is the line where the cut goes, would be interested to see how it cuts.

Please select the Accept as Solution button if a post solves your issue or answers your question.

[Anonymous]

You mentioned that you weren't quite sure what we were using this for. If you are interested, there is a short video below of a system someone else is using specifically for tube notching. We will be using our machine to notch tubes for SAE Baja, Formula SAE, and Nasa moonbuggy teams at our college. This method should be much faster, more accurate, and easier than all of our other methods.

[kelly.young]

@Anonymous that's a pretty sweet setup. What are you looking to get out of Inventor other than the coping cut, simulation or animation as well?

There is a much better way of getting the line you need than I initially showed using surfaces or a 3D Sketch or split at plane might work though one wall. 

Friday Challenge: what's the best way to do this?

If anyone reading feels like joining in, post your .ipt attempt, I've got a few ideas brewing. 

Please select the Accept as Solution button if a post solves your issue or answers your question.

[SEANT61]

Not necessarily an IPT attempt, but here is something to consider.

Lacking that fifth axis, a 4 axis setup as shown in the video will only make perpendicular cuts.  The inside tube face, then, becomes more important.  The resultant gaps (see screencast) may even assist welding. 

The process becomes slightly more complex, and more critical, once non-perpendicular mating angles are addressed.  

[SEANT61]

http://www.cadtutor.net/forum/showthread.php?67512-Creating-tube-miter-correctly&s=fcabf75c5e53b4a23...

had a similar discussion.

[S_May]

[Anonymous]

In your video you mentioned using the rip tool. It seems like it would be an easy solution except I can't get it to work. Most of our tubes already have a plane running through them lengthwise, so split at plane might be an easy solution. My Inventor skills don't extend much past the basic 3d modeling tools, yet.  

[Anonymous]

I've been playing with the split tool and using a plane, but haven't come up with a way to only split one side. Since it splits at the plane it splits the tube in two. When I go to make a flat pattern it wants the part to be turned into a component, which removes the split sections. I tried using a sketch, but it somehow did the same thing even though the sketch only goes through one side of the tube. 

[JDMather]

Attach your file here and I will create video demonstrating the correct way to solve this problem.

[Anonymous]

An example tube file is attached below. 

Thanks for the help!

[JDMather · Accepted solution]

This is the basic method.

I often use Frame Generator or Multi-body solids and then Derived Components which is a slightly different method based on this method.

[Anonymous]

I hadn't even thought about making the cuts perpendicular for the cutter. We have always used hole saws or insert endmills that cut exactly like the drawing. Just a lot more trial and error with that. 

Thanks for the video, it was very helpful!

[JDMather]

Oops, when you posted this I assumed you were using the same process.

I have seen some people use hand grinder to cope ends and needed a paper template to wrap around the pipe.  In that case, the process would be to use the Outside rather than Inside and Thicken only by thickness of sheet of paper template.

[Anonymous]

We are going to be using the same method as shown in the image you posted. Our machine just hasn't arrived yet. I'm just working ahead to get the drawings and software stuff figured out. That way we can hit the ground running instead of having a huge learning curve with the machine sitting idle. 

[S_May]

beautifully explained

[SEANT61]

With the available CNC capability, why not process for indexing?  This may minimize the need for custom weld jigs.  

If the cutting equipment allows for "Shadowing", the Mating IDs could even be etched at the appropriate locations.

[S_May]

Hi @Anonymous,

here ilogic controlled

step 1

step 2

step 3 DXF to laser cutter