Rectangle Coil

[burninin1]

Ok I’m up and running with Inventor 2008, Man a lot of new stuff from R8. Hope you guys can help out here.
I need to make a coil that wraps around a rectangle 4 times. The rectangle dims are .25 W x .5 H x 3” L the coil wire is .0313 in diameter and the inside radius will touch the outside of the rectangle. The rectangle will have filet edges that are .0625. Not familiar yet how the wire and piping work. Will I use one of those methods to make this coil or am I going to use the loft tool? I’m not to sure how to make a coil using the loft tool.

[James.S]

I just had a wee play round and came up with this, i know its not the size you specified but it hopefully gives you an idea on how to do something like this, or at least one way to do it.


And by the way it would be really handy if .ipt and .iam were valid file extensions when uploading files to a post, hint hint nudge nudge moderators.

[JD Mather]

And by the way it would be really handy if .ipt and .iam were valid file extensions when uploading files to a post, hint hint nudge nudge moderators.

And by the way it would be really nice for those of us on slow connections if those posting ipt files would first roll up the End of Part marker in the browser before zipping the file. In this case the file would have been a 73kb download instead of a 320kb download. Hint hint nudge nudge James S.

[burninin1]

Thanks for responding to my question James. Not to sound like a newbie too much here… But I don’t get how you made this coil without work planes or Work Axis. Or did you delete them? Not to bug you too much, but could you tell me briefly what you did.

[JD Mather]

Here is another method. Pull down the red End of Part marker in the browser step-by-step to see how it was created. To change a dimension simply click on the dimension and then click rebuild.

The path is created with a 3D sketch with Autobend turned on. The profile was created on a workplane perpendicular to the start of the path.

[James.S]

Heres a bit of theory or a how to of the process of how i did it and why each step was important:

3D sketches are real handy for doing weired shapes especially when you want to sweep a profile with this in mind i started out with sketch 1, I created some lines to represent the pitch and amount of coils and also define the width of the spring.
3D sketches rely on having some points in 3d space that you can pick up on to make your sketched line this is what we are doing here.
Sketch 2 is on a tangential plane to sketch 1 this is to get a variable offset for the next plane (the other side of the spring) in this case it is the same as the width of the spring in sketch 1 because we want the spring to be square, after i did that i put a work plane parallel to sketch 1 on the width point on sketch 2 and created a sketch on that work plane this is sketch 3.
Sketch 3 defines the other side of the spring opposite to the sketch 1, i sketched similar lines on this sketch to sketch 1 but the main difference is they are half a pitch different and pointing the other way as it is the opposite side.
Then i made a 3D sketch and used the line function to connect up all the ends of theses lines created in sketch 1 & 3 and then after i had finished connecting up those points i turned off the visibility of sketch 1&3 and then connected up all the lines in the 3d sketch.
This this last step was done because to sweep you need a complete path in one sketch you cant join 3 sketches together to make one path or at least thats my understanding of it.
After that i filleted all the corners of the 3D sketch so the spring had rounded corners rather than square ones, then i made a profile of the circle on sketch 2 to sweep and swept the profile on on the 3d sketch, this is how i made it.

Although i did one thing wrong when i made the circle profile to sweep i should have made it tangential to the first line of the coil rather than on sketch 2 because sketch 2 is not tangential to the coil so effectively i have swept an oval around the coil.

So here is the corrected model, (and its all rolled up just for you jmather)

I did this by creating a work plan tangential to the line on the end of the coil and sketching a circle on it and then sweeping that.

I hope this all makes sense its not particularly well written in places but you should get the idea, hope it helps you understand how it was made.

[JD Mather]

Here is a third alternative.

[James.S]

That last alternative (the third alternative form jmather) is a bit of a complicated way of doing things, well i found it was anyway and it got a bit confused when it was re-sized and did weired stuff i think the first 2 ways were a bit more stable.

But at the end of the day there are many ways to skin a cat and you just have to find a way that works best for you, that understand and is stable so you only have to do it once and not waste time repeating it.

[Ron Oldenbeuving]

Here is a third alternative.

I'd like to thank you for the help you've given people in these forums over time.

[burninin1]

jmather & James.S
Thanks for your help