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How to model a propeller / fan blade

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How to model a propeller / fan blade
I've been trying to figure out how to model a propeller for a fan but I've been having trouble. The sweep tool creates strange bends that doesn't correctly mate with the circular middle axis of the fan. The helix tool creates weird insertion points that makes it tricky to line up. Has anyone successfully modeled a propeller in varicad?

I have two questions:

What is the correct tool to model a working propeller and how?

How can we change the angle of the x/y/z axis of the insertion point of an element?

Thanks.
solution
well I figured it out. For future reference, you use the lofting tool. Draw a cross section then right click and create a new plane. Offset that plane by a certain distance and create a new cross section of the fan blade. I think you have to keep the number of lines the same in each plane when using the loft tool.
Solution
Hi:
Are you willing to share your findings in more detail, with an example even.

Thank you,
Bojan
Details
I took some screenshots that might be helpful but I can't attach it to this forum.

Imagine cutting a fan blade/propeller in multiple planes.
Each cross section would look like a curve.
The curves closer to the center of the rotation axis would be more vertical while the curves outside would be more horizontal.
In my case, I made the fan blade using 5 planes.
Each plane consists of 2 lines (top and bottom) and 2 splines (left and right) which makes up the curve.

1) First I clicked on "sketching (2d drawing in 3d space)" and picked x/y (it doesn't really matter which plane you pick)

2) Draw your curve for cross section of the fan blade.

Note:
I had 2 lines and 2 splines that defined this cross section. For the next cross section make sure you have the same amount. (for example you can't decide to just use 2 splines for the next curve... it has to be 4 things). Also using multiple vertical and horizontal construction lines will help a lot to drawing the plane.

3) Right click and select "multiple drawing plane" and make a new drawing plane. It would be helpful if you copy the 2D objects as a point of reference for your new curve. Make sure you delete these 2D objects later.

4) use the arrow and move the plane out by a certain increment to start drawing your next plane.

5) Draw the new cross section of the fan blade on this new plane.

Note:
Make sure you still keep the same amount of 2D objects (I had 4 for my curve)
This new curve will appear more horizontal than the last curve since it's farther away from the center of the fan. When you are done, you should see green lines that connect the 2D objects between the 2 planes.

6) Repeat step 3 - 5 until you have the desired amount of cross sections you wish.

7) When you done with your cross sections click on "define method of solid creation" on the hovering toolbar.

Note:
This toolbar has the text "click ok to finish profile sketching"

8) Choose loft multiple profile and click ok.

Note:
If you can't click ok the most likely problem is that you don't have same amount of 2D objects in each plane. Another problem could be that your lines or splines don't form a closed loop and you have a gap somewhere. Using a lot of construction lines should be extremely helpful to stop this from happening.

9) choose an insertion point and finalize your solid



When you are done just move your fan blade to desired position. Make sure it intersects with the central axis of your fan. Click on rotation around axis and make multiple copies of fan blade around the central axis. Then when you are done, use boolean add to combine the central axis and all the fan blades into a single solid element.



I also figured out the answer the previous question of my thread. You can change the axis of the insertion points without rotating your solid. This can be accomplished by "Additional Rotation Around (X/Y/Z) axis." You can find this easily by seeing the "+" sign in the icon under the "3D location" toolbar. This may help you a lot if your axis for the fan blade is off. You may have to create a cube to use as a plane of reference for this rotation offset ( you can just delete the cube later ).

I hope this helps.
If you have any questions just ask.
Tips
One thing I forgot to mention is that you have to cut a circle around your fan blade when you're done. This is because from the top view, each blade would look like a triangle, but fans are circular from top view.

Also, try using on 3 planes for your first try. The more planes you use, the more problems you may encounter. It took me about 4 tries before I got it right.

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