Rhino users, could you make it?

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Mac790

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Ok, I was thinking about starting this thread in other category (like hangar flying, etc) but because I'm asking about metal part maybe it's a better place for it.

In short I was trying to get a flat template out of this pipe (I have about 30-40 more), but I have some problems with current software, it should be easy with Inventor but unfortunately I don't have one at the moment, probably I could download one, I still have a student account here Autodesk Education Community but I was thinking also about Rhino, I can download demo version, I actually downloaded it a couple times before, but I haven't found time or patience to learn it so far, I prefer mainstream softwares with a "tree".

Anyway do you have any idea ho to get a flat template out of it?

I have CNC laser cut service in area, they can cut those pipes for me with ease, but I'm looking for more affordable approach, they idea is to get flat template, print it in 1:1, glue it around a pipe, and finally cut to proper shape with an angle grinder.

Seb
 

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planebuilder

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Ii use rhino all the time. There are two ways to do on this, if the shop accepts a .STL file, or an .igs file . Export a properly modeled tube as either of these formats and send it to them. If you require a flat pattern, then you need to explode the polysurface (solid) and unwrap the outer surface. (Actually you should offset the outer or inner surface 1/2 the thickness of the material so the flat pattern is on the neutral axis) You need to split this surface so you can unwrap it. There is a function called develop that will do this. But you need to start with an edge.
 

Mac790

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i use rhino all the time. There are two ways to do on this, if the shop accepts a .STL file, or an .igs file and send it to them. If you require a flat pattern, then you need to explode the polysurface (solid) and unwrap the outer surface. (Actually you sould offset the outer or inner surface 1/2 the thickness of the material so the flat pattern is on the neutral axis) You need to split this surface so you can unwrap it. There is a function called develop that will do this. But you need to start with an edge.

Thanks for info, I'll download a demo version in the next few days and try it, surface was created at 1/2 thickens of the pipe (in the middle) and it's splitted, hope it will work.

Thanks again.

Seb
 

Rienk

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Thanks for info, I'll download a demo version in the next few days and try it, surface was created at 1/2 thickens of the pipe (in the middle) and it's splitted, hope it will work.

Thanks again.

Seb

I'm confused... what good does creating a surface using the neutral axis do?
You're going to glue the template to the outside of the pipe - not the middle... you'll end up with a gap. Though this may not be critical, then neither is designing around the neutral.
The best would be to design the template based on the OD, but have the outer cut line based on the neutral?

One more suggestion.
If you're only going to make one of each, then paper templates are fine. But if/when you decide to make multiple (or go into production) you may want to consider transferring all the cuts to a slightly larger tube (one that the finished tube can easily slide into). Then, you can use this as your template, without having to wrap it each time - saving plenty (of time).
 

Autodidact

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He's going to glue the pattern to a flat sheet, I think, and then bend it; the inner surface will shorten a little and the outer surface will lengthen by the same amount. The neutral axis is the only region that will not distort, since there is only shear stress there and no compression or tension.

I like your mass production idea, though.
 

Mac790

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I'm confused... what good does creating a surface using the neutral axis do?
You're going to glue the template to the outside of the pipe - not the middle... you'll end up with a gap. Though this may not be critical, then neither is designing around the neutral.
The best would be to design the template based on the OD, but have the outer cut line based on the neutral?)

Sorry Rienk for my unclear post I was in hurry (I was polishing today another three plugs).

I didn't get Planebuilder hidden message at first time, he was trying to say that it's possible to create in Rhino a flat pattern out of surface object. If you take a look at software like Solidworks, Inventor, etc, there is a "sheet metal" module with flat pattern tool, but you can't create a flat pattern out of surface object, you always have to add thickness first.

My pipes were generated with a "frame" tool, there are solid objects, I created a surface in the middle of a pipe, next I remowed solid part, next I was going to export surface to Rhino and add thicness (in my case 0.75mm to each side) next I was thinking about getting a flat pattern out of it. But because it seems that with Rhino I can create a flat pattern out of surface too, next time I use OD surface instead of "middle" one.

Hope it's clear now, sorry with my English I can't write it clearer.

One more suggestion.
If you're only going to make one of each, then paper templates are fine. But if/when you decide to make multiple (or go into production) you may want to consider transferring all the cuts to a slightly larger tube (one that the finished tube can easily slide into). Then, you can use this as your template, without having to wrap it each time - saving plenty (of time).
I'm going to build only one chassis (those pipes are for a car frame), it's not mine design I'm only testing at the moment, if I decide to go with my own designs, definitely I would use CNC laser service.

Seb
 

Rienk

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Hope it's clear now, sorry with my English I can't write it clearer.

I'm going to build only one chassis (those pipes are for a car frame), it's not mine design I'm only testing at the moment, if I decide to go with my own designs, definitely I would use CNC laser service.

Seb

Well, if you can't write English properly, then don't bother coming to the US - we already have a majority of the population who can't do that ;)

I don't mean to hijack the thread, but I am very interested in building/buying a CNC tube cutter.
My ideal would be a simple XZ cutting head, with a rotary axis. But I would like to take it up a notch by having automatic feeder (with servo controlled roller) so that all the pieces can be cut to size/shape, all out of full length tubing.
Anyone seen this done?
 

Mac790

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Planebuilder,

Thanks again, it works :ban: I just downloaded demo version, this is what I was looking for :). I have to install my Space Pilot, because working with Rhino without it will make me crazy :gig:.

BIG Thanks Again!!

Seb
 

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Mac790

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It worked fine for most tubes but with some I had strange troubles, in short if you take a look at pic one you will see a three separate flat patterns instead single one, it wasn't a big problem because I joined them manually pic2, but I would really like to know what was wrong with those tubes, any ideas?

Unfortunately I can't upload STEP file here, so you can't take a look at it.

Seb
 

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