How to morph a shoulder strap from straight into half circle?

Hi I am attempting to model a simple handbag. So the strap that will attach to both sides should be flat
but bend into a 1/2 circle in between the two bag walls where they would be stitched together?
How do I go about without to many plug ins etc?
I put the area where the change should happen in different colour
The leather is like 5mm thick so I made the model quite thick as often when too small to make circles seem to be a problem. My setting is in mm
Thank you
STRAP for bag.skp (190.0 KB)

Something like this?

Create the path and then apply ‘Follow Me’.

You can overcome this by using “the Dave method”.

My guess is @Voicefromwithin wants a curved strap on the sides of the bag that transforms into a flat strap that goes over the shoulder…
I think this should be done with Curviloft…

Hello Thank you. But no. The strap of a bag is flat over the shoulder The part that imperative should go from flat to curved in the area that is “darker” only. and yes the bottom part that should ensue between the two wall will be curved like you showed.

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Hello Yes you are right. I guess curviloft is another pay plugin?

No, it is free

You do have to make an account for Sketchucation, but it is free too…

Hello thank you so much, found it SKetchucation and it was for free.
STRAP for bag_cuviloft.skp (237.1 KB)

OMG why did I know come across this before or ask before.
Battled over so many trials of impossible shapes
in my autodidact ways…


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You do need to reverse the face of the Curviloft section.
The over the shoulder part is easy to make with follow-me.
To make the Curviloft section match with the rest you’ll have to soften and smooth some lines on the other parts or unsoften some lines on the Curviloft part. You can select them by making them visible: view - hidden geometry…


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Thank you very much

Thank you very much
It looks nice but my bag is very stiff leather
I here by attach my attempt to model it
on a table or chair with the straps open
and it not looks very good
I have tried two path ways
one along a circle that follow in perpendicular from the top part to the bottom part
and one in a curve.
I guess the size may be the problem as the thickness

is 4mm only
I cut away everything
I cant’s seem to make it smaller than 23.4MB
Here is left strap version, right and both made with “curvyloft”

Thank you very much for your advice

Hello how do you keep all this under 16MB file
I tried to upload my near skeleton and it was still 23.4MB
May I ask what do you use to save the recording of you actions like that?
Thank you for your time and effort

I wanted the strap to come down as in my SK file UPEN loop and flat to show how it’s made

I’ve downloaded your file, unfortunately it’s still not quite clear to me even with the file what you are trying to achieve, can you include a photo or drawing of how you are expecting the strap to be? If you don’t need to bend the strap on it’s long axis into a more horseshoe cross section or complex shape then follow me or upright extruder might be a better option, but as I said I don’t quite understand the goal here.

Your file is stuck at 24MB because perhaps you do not understand how components work. If you insert a component into your file from the 3D warehouse or make a new one yourself it is saved as part of your file, with 1 instance showing, if you move/copy another one you have 2 instances of that component in the model. If you erase them all you have 0 instances present in the model but this does not delete the component. It is still saved as a part of your file waiting to be re-inserted at any time. This is a major advantage of components, that they cannot be easily deleted and so lost, textures work the same way. This file has several interesting components still saved in it which you must have inserted at some point and then deleted from the model space. If you open the Component Browser and click on the in-model list (the little house icon) you can see all the components still attached.

The way to clear old unused components is to Purge the file. Go to Window>Model Info>Statistics>Purge Unused. This will truly delete every component and texture that is not currently being used in the model space but is still attached. When I perform a Purge on this model it becomes 142kb.

I and many others here on the forum use LICEcap to create tutorial gifs.

I will study your mail and help
All of the model is MY making
only thing I imported at one time is an apple tablet to size to make sure
if fits into my pocket with a bit of space around.
I need the strap OPEN for a specific reason that I can’t put here
but it has a purpose and this is an idea of mine I am working on
and don’t or can’t put on the internet in full at this time
WOW it’s quite amazing I deleted all the pattern of my bag
and everything else to the two portions of the shoulder strap
I just want to lay relaxed and open on each side of the bag for
and aesthetic purpose and to go with a graphic that will explain
certain aspects of my bag.
All I wanted it to twist the strap from vertical to horizontal in a
“as natural looking” way as possible
By using the loftycurve (which I ignores till a few days ago you pointed it out)
it gives me a volume that is thicker than the 4mm x 4cm
which makes it look odd.
I don’t mind the curve to be longer but then it should stay thin as the leather while it
twists from vertical to horizontal.
I will do the practice the purge also. I knew about it but must admit
I rarely use it.
Thank you so much for your kind assistance will upload again tomorrow
after following your advise.
Sorry for being somewhat mysterious but with the internet
anything such as a new concept if not kept under wrap is like giving it away.
Thanks again

OK, well there is an unused component of a 3D person in your model, several of them actually, and that’s whats keeping your file size so large.

I’m not much clearer on the goal. Is this something like the shape you’re wanting? The straps you included seemed to be trying to turn up at 90˚ like this, while twisting.


Hello. Good morning

Yes this looks so perfect so much better than my attempt
I will try this again without the center 1/2 circle
I am trying to purge etc…
will come back with it.
Thank you so much


Sorry for bothering you again
but I try and try with or without path
I still get like an elephant ivory task
I have distanced the two starting points by 15cm
Is there any special setting I must enter inside the curvyloft TO KEEP the shape
while it extrudes along the path?
I just can’t find the right setting
I don’t need the above curved bridge type that goes across
just from the last true horizontal plane that can link to the attachment of the strap
to the true vertical plane that will link to the end of the open strap
in my representation the strap closing belt loop is open
Thank you
I love your website so much creativity!
00_STRAPtest8.skp (195.2 KB)

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00_STRAPtest8_x10size.skp (245.4 KB)


I think I tried everything
I multiplied the size by 10 here for it to be bigger like someone explained the Method
then I linked the far back corner of the horizontal strap end
to the left bottom of the vertical strap end

I did the same in the centre etc
I always get like this spaghetti
00_STRAPtest8_x10size_likeAsail_WHY.skp (247.3 KB)
that does not follow the path
I tried the other splice method also nothing usable
00_STRAPtest8_x10size_NEARLYlikeAcobraSNAKE.skp (745.2 KB)

I CAN NOT get the strap to bend like your gif animation
what is the size of your two rectangle and what is the path shape and
from which point to which point ?
It still a mystery to me, sorry