Warp factor needed

bending
warping
twisting

#1

Is there any plug-in (or method) that’ll allow me to axially bend or warp a plane (or volume)? See blue arrows, top picture.
I’m drawing a fan’s propeller, which is, as illustrated by the side-on view at bottom, twisted along the rotation plane.
The hub’s receiver section is bent the same way (white arrow, bottom picture).



Turbo-Jet Engine
#2

I believe Fredo’s Curviloft plugin could do it, but I don’t know how to do it myself.
http://sketchucation.com/pluginstore?listtype=1&author=0&category=0&search=curviloft&submit=%3F
Most of his plugins also require FredoLib to be installed too. Read the instructions for Curviloft to check.

You could do it manually by making horizontal slices of your blade aerofoil, then rotating them a small amount each, but it wouldn’t be straightforward.


#3

Adding to John, there is a bend tool in the “Fredo-scale” tool set that might be worth a look. Again you will need Fredo lib to be installed for it to work.

Fredo scale.
http://sketchucation.com/pluginstore?listtype=1&author=0&category=0&search=Fredo+scale+&submit=%3F

Libfredo6
http://sketchucation.com/pluginstore?listtype=1&author=0&category=0&search=Fredo+lib&submit=%3F

The example to the far right was done with the bend tool, to give you an idea. The twist tool (of the same set) was used to twist the shapes, this may even suit better. Or maybe a combination of both.


#4

Thanks for those examples. I have FredoScale installed, but rarely use it, and didn’t remember it has the Bend and Twist tools - a useful reminder.


#5

I reckon the twist will do that easily, re looking at it.


#6

Certainly looks like it from the OP’s photo. Some more complex propellors might also need a bend.


#7

OK, thanks, fellas…
I’ve got those tools installed, I’ll see if they can be of help, and follow-up here with any positive results. Seems to me that the shapes bent in the illustration are quite simple compared to the ones I’ll be working with, but it’s definitely worth a shot.
The problem I’ve got with Fredo6’s output is the paucity of training documentation produced for it, as well as the somewhat arcane UI’s provided. I use Curviloft often for its basic capabilities, but I haven’t managed to make any headway towards understanding all the bells and whistles it came with.
Again, thanks…


#8

Documentation is in the SketchUcation forum for the extensions. The direct information links are available on the on the pluginstore’s page - ably labeled “more info”.


#9

That’s what I was referring to; Those video and pdf instructions exist, but they’re far from straightforward. By the by, the tool I was looking for is called Box Twisting, in the FredoScale suite. It works, but wreaks havoc on complex surfaces. I think I’ll circumvent that problem by just bending a wireframe outline, and then “skinning” it with Curviloft.
Consider this as solved. I’m checking the box, but I’m unclear as to the attribution, if any.


#10

I think there will be trial and error because of the complexity of the thing. I might be simple, it’s just finding what works.


#11

Out of curiosity, how are you using the blade you’re drawing? Is it just to represent the a fan blade? I don’t think you could get adequate aerodynamic info out of the SketchUp model so your fan blade probably doesn’t need to be incredibly accurate. I drew the outline for the blades on the face in this model using Bezier curves and then Curviloft to skin it. Joint Push/Pull made the thickness.


#12

This model is basically an exercise in extensions use. All of the surfaces in the final assembly will be curved in at least one direction. Having flat surfaces make up the propeller would make it stand out like a sore thumb.
See for yourself:


#13

I’ve had a few attempts with Curviloft, which I weren’t very successful with, I don’t know it that well really. Then I tried bending then twisting which gave too much face distortion for my liking. In the end I just twisted by 12 degrees for a happy medium. Solid inspector reports solid, but Sketchup does not however.

I’m sure there’s plenty of ways to do it, here’s mine so far:


#14

Nice…
I’ve stopped trying for today, but my next crack at this’ll involve your solution and the scale tool. I’ll make the blade thinner to start with, and then scale up its thickness to steepen the resulting distortion. Should be interesting.
After that, the next hurdle: The narrowish, outside tip of the blade actually curves in the opposite direction!
I guess the radial bend extension will rear its ugly head…
Thanks for your interest and time, I really appreciate them.


#15

I don’t mind having a go just to see what can be done. It’s a start I suppose, your obviously wanting to take it much further. Post back, it will be good to see.


#16

And, also, this is an exercise in accurate modelling, and the fan I’m working on has a propeller that isn’t flat-bladed…
For me it’s all a matter of finding out how to solve problems. No other reward than the actual solution(s), no criteria to meet but my own…


#17

You got yourself a deal…


#18

The blades in my model are twisted, too.


#19

This would be an ideal candidate for SUbD.
Give me a few minutes.


#20

You might try intersecting your blade outline with a skewed cone or cylinder: