Sweep along a helix results in rotation.

[rthardinN22EC]

Hello all,

First let me start of by saying that I am relatively new to Autocad so any help is appreciated.

I am trying to draw a coil made out of rectangular wire.

I started by making a helix, I then made a line where I needed the helix to stop in order for both "ends" to be facing the same direction. I then used trim to make a break at the point where the helix and line intersected and deleted the line and unneeded portion of the helix. I then made two more lines to extend each "end" of the helix in order to make "wings" or "leads" off of the coil. I lined everything up correctly and used join to make one object.

Next I made a rectangle, representing the cross section of the rectangular wire the coil is meant to be made of. I used 3drotate to position the rectangle so as it was perpendicular to the end of the leads off the end of the coil. After that I used sweep to make my coil and changed my view to shaded.

It was then that I noticed two problems, the first much more severe than the second.

First, at the top of my coil the rectangle (wire) is positioned correctly and everything starts off good, but as the coil descends the rectangle/wire begins to rotate and has a substantial rotation/bend by the end of the coil.

Second, each of the leads/wings that I added to the coil have a visible line both in wireframe and shaded view where they meet the original coil.

I will attach a copy of my file for reference In case I was not clear in my explanation.

Where did I make a mistake? What should I do differently to remedy these problems?

Thank you for any help or advice.

[john.vellek]

Hi @rthardinN22EC,

When you perform the sweep, check your Alignment option and keep the profile perpendicular to the helix path.

 How are you creating the leads? The same rectangular profile with a presspull?

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

[rthardinN22EC]

Thank you Mr. John Vellek, but I beleive we may be performing the sweep differently from each other.

I deselect everything, type sweep and press enter, select my rectangular crosssection and press enter, and finally select my helix and press enter. I don't get an option for alignment the way I have done it, perhaps I should do it a different way.

It also may be caused by the way I have made my leads. I didn't use presspull as I am unaware of it or how to use it. I simply made lines where I wanted the helix to extend to make leads and joined them to the helix with "join" and the sweep was the last thing I did.

I will upload a version of my file up to, but before, I perform the sweep. Maybe that will make it more clear as to what I did.

Thank you for your advice thus far.

EDIT 12:50PM: I forgot to mention that I reattempted the sweep (ensuring the rectangle was lined up) looking for an alignment option, but did not see one. The problem is still there performing the sweep this way, that may be my problem.

[john.vellek]

Hi @rthardinN22EC,

I made a quick video of how I am performing the sweep.  Let's see if that gets your version to orient correctly on the helix path.

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

[rthardinN22EC]

Okay, I followed your video on the helix with leads that I had previously made and it resulted exactly the same(using the alignment option this time.)

After that I tried to follow your video exactly with a new rectangle and new helix and that worked exactly as described. That solves my rotating/tilting problem.

Now if I don't add the leads to the helix before running the sweep, what is another way to accomplish the same thing?

Meaning how would you extend the ends of the coil,  in a straight line, off of the helix (after the sweep has been performed)?

Thank you for all of your help thus far, especially going the extra mile and making a video to show me that it was possible to click on arguments/flags of a given command, I did not know that was possible and know it will prove very useful in the future. You have been very helpful.

[john.vellek · Accepted solution]

Hi @rthardinN22EC,

I am glad that my video helped. I prepared another one that shows the leads  attached to the helix. I do not want to make them part of the path because that will make the profile twist for some reason.  So, I made my rectangular profile and made a duplicate for later use. The first one I sweep along the helix with the perpendicular alignment as I showed in my first video. Then, I presspull the duplicate profile to the length I desire and then add it to both ends of the helix. To complete the solid, I then use join to make a single solid.

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

[leeminardi]

If you only have a swept rectangle along a helix and do not have the centerlines of the straight leads, you can make a straight piece with push-pull as John did or extrude a rectangle and then use align the position it at the end with the correct slope.

[j.palmeL29YX]

Here another way - see screencast (created in ACAD 2016).

https://autode.sk/2Mapw2m

cadder

[rthardinN22EC]

Sorry for the delayed reply.

Thank you everyone, that has completely solved my problem and I even know other ways to accomplish it too now, that's great!

Thank you to those of you whom took the time to make a video to clearly show me what it was that you were doing, that really made all the difference.

John Vellek, you stayed with me through this issue and made sure to help me get to where I needed to be. I sincerely thank you for all of your help.

Until I mess up again, thank you all, have a good day.