Modeling a Tapered Spring - Sweep resulting in "Topologically Invalid Surface"
Modeling a Tapered Spring - Sweep resulting in "Topologically Invalid Surface"
(OP)
Hi, I'm having trouble modeling this spring.
I can get the desired profile curve, but I cannot get it to complete the sweep - either as a surface or a solid. I need a solid as the end product, but I'm open in how to get there.
Any help would be appreciated, I've attached the file below.
Also, this is my second attempt at this spring. My first attempt I tried my normal approach using the "helix" curve feature with the variable pitch option.
This method using surfaces has given me better results with some parts in the past, so I tried it, but still no luck.
Thanks again!!
I can get the desired profile curve, but I cannot get it to complete the sweep - either as a surface or a solid. I need a solid as the end product, but I'm open in how to get there.
Any help would be appreciated, I've attached the file below.
Also, this is my second attempt at this spring. My first attempt I tried my normal approach using the "helix" curve feature with the variable pitch option.
This method using surfaces has given me better results with some parts in the past, so I tried it, but still no luck.
Thanks again!!






RE: Modeling a Tapered Spring - Sweep resulting in "Topologically Invalid Surface"
Yet another reason why 3D sketching is not a great tool to utilize... I stay away from 3D sketches, due to there instabilities.
Scott Baugh, CSWP
FAQ731-376: Eng-Tips.com Forum PoliciesBerry Plastics
Cad Admin\Design Engineer
GEASWUG Greater Evansville Area SWUG Leader
www.scottjbaugh.com
RE: Modeling a Tapered Spring - Sweep resulting in "Topologically Invalid Surface"
Dan
www.eltronresearch.com
Dan's Blog
RE: Modeling a Tapered Spring - Sweep resulting in "Topologically Invalid Surface"
Is used the same dimensions, including the .138 diameter and it works fine. I believe its the style of the path used. check out my file.
Regards,
Scott Baugh, CSWP
FAQ731-376: Eng-Tips.com Forum PoliciesBerry Plastics
Cad Admin\Design Engineer
GEASWUG Greater Evansville Area SWUG Leader
www.scottjbaugh.com
RE: Modeling a Tapered Spring - Sweep resulting in "Topologically Invalid Surface"
Do you happen to know why your modeling technique works and mine did not?
Prior to the file I attached, I had tried this using a single helix (variable pitch) and the same curve for the hook part, joined as a compound path the same way yours is, and that also failed.
I'm just trying to understand why Solidworks likes one path and not another so that I can avoid delays in the future.
Thanks again!
RE: Modeling a Tapered Spring - Sweep resulting in "Topologically Invalid Surface"
I took your example and I tried to re-create it because I wanted to learn and I also wanted to re-create it using our file template, and I do not get the same results.
In my model, I cannot get a single sweep feature to follow the entire compound curve path. (file attached)
The only difference from your model is I've set up the equations, but the end dimensions are the same, and I even went back through yours and I'm not seeing what I did wrong.
RE: Modeling a Tapered Spring - Sweep resulting in "Topologically Invalid Surface"
I was selecting the path and profile before creating the sweep, and for some reason the path was coming in as an "edge" which was not the whole path. I simply cleared this and re-selected the compound path and that fixed it.
However, in my model I get an ugly surface that bulges out at each "joint" in the compound path, not smooth like yours.
I checked and the feature options are set the same, so I'm not sure what I did wrong.
Any ideas?
RE: Modeling a Tapered Spring - Sweep resulting in "Topologically Invalid Surface"
I had to turn off path start and end tangency.
Thanks again Dan, your file was extremely helpful!!