how to design an impeller

[turcomemo]

hi everyone i try to create an impeller on the solidworks but i didnt understand technical drawings can anyone help me how can i do it ?
http://img517.imageshack.us/img517/9818/wkl50gc3.png
http://img517.imageshack.us/img517/362/0000024ek1.jpg

[jamiedaugherty]

You are going to have a heck of a time modeling that in SW. There is a way to create a spline (or maybe even a surface) as defined by a set of points. I think that's what you are going to have to do. You are probably going to have to create some weird planes and stuff too. It's not going to be easy!

Honestly, I don't think the prints that you have, at least not the ones you posted, have enough information to create the geometery. Maybe there is something I'm missing, but it looks like you need the coordinates of curves for 2-2, 3-3, 4-4, 5-5, 6-6 etc. Without those points in space it's just a pretty picture.

[Tomorrow_man]

Oh, there may be enough info. Need to zoom up a bit on the right hand side of the .png drawing to see the detail and sizes. Used Google translate and found out it says 3mm thick at the hub end. I'll give it a go, what version of Solidworks are you using?

TM

[Tomorrow_man]

I did this in 2007. It's a start. The impeller feature will go on the inside.

[jamiedaugherty]

Originally Posted by Tomorrow_man Oh, there may be enough info. Need to zoom up a bit on the right hand side of the .png drawing to see the detail and sizes. Used Google translate and found out it says 3mm thick at the hub end. I'll give it a go, what version of Solidworks are you using? TM

SW 2007 also. From what I can tell, that drawing shows the blades to be slanted, sort of like a propeller blade. The 4-4, 5-5, 6-6, etc lines are constant curavature lines I think. That's going to be super complicated to produce in SW. At minimum you are going to have to use the surfacing functions. I've not used them too much so I can't really help you much there.

[Tomorrow_man]

I agree, surfaces may be the way to go.
I was also thinking about using a 3D spline as guide path for a cut, once the basic blade shape is made.

TM

[Tomorrow_man]

The drawings are for two different but similar impellers.
The older taped drawing gives nearly all the info for creating the part.
On the older drawing the 2-2, 3-3, 4-4, etc. corresponds with diameter dimensions in the cross section on the right, a development table so to speak. The cleaner drawing shows the same thing, but shows the arcs intersecting, where the older one shows the interscects as points.
There seems to be some info missing on the cleaner drawing, it's not showing the full section view. I'll use the older drawing for the model, a cleaner scan of the section view would be helpful.


TM

[Tomorrow_man]

Here's a cross section. I printed the drawing smaller, gives more detail to the numbers.

I'm going to use a loft to create the 2mm offset, seems like the simplest way when using sketch geometry. Same sketch on the inside of the two bodies that were created with the revolve.

turcomemo, are you a student and this is an assignment?
Also, check the help files in Solidworks for revolves, that should get you started. And, use a eye loupe to read the drawing, all the information is there.

I'll finish the model and post the image.

TM

[JerryFlyGuy]

Actually, its not THAT tough. I've done a turbo impeller once which had reversing blades [started out tilting one way and ended up just past perp the other way at the outter [radial] tip] In one view the blades look like they are just angled from radial and in another one they look like they are some form of an involute. Is the point where they connect to the hub in a straight line or what am I missing??

If this is the case and they are simply tilted at the outter [farthest side from the impellar backing 'disk'] edge. Then a loft will do the job in one go. It will take some guide curve geometry but thats no big deal. I'll see if I can find some pic's of the model I did.. had renderings of it and everything..

[turcomemo]

Originally Posted by Tomorrow_man Here's a cross section. I printed the drawing smaller, gives more detail to the numbers. I'm going to use a loft to create the 2mm offset, seems like the simplest way when using sketch geometry. Same sketch on the inside of the two bodies that were created with the revolve. turcomemo, are you a student and this is an assignment? Also, check the help files in Solidworks for revolves, that should get you started. And, use a eye loupe to read the drawing, all the information is there. I'll finish the model and post the image. TM

first of all thank all of you for helping i graduated last year from foundry school but as you know foundry school doesnt teach so complex teachnical drawings but i want to learn it and modelling on the solidworks (i already use solidworks for long time but as i told i cant understand drafting of impeller)
its not important that i have to model these drawings i can just find these so if you have some impeller drafting i would like to study and trying to modelling

[Tomorrow_man]

Originally Posted by turcomemo first of all thank all of you for helping i graduated last year from foundry school but as you know foundry school doesnt teach so complex teachnical drawings but i want to learn it and modelling on the solidworks (i already use solidworks for long time but as i told i cant understand drafting of impeller) its not important that i have to model these drawings i can just find these so if you have some impeller drafting i would like to study and trying to modelling

I didn't intend to press 'quote'.

ahh, good exercise then.

TM

[tobyaxis]

I don't know about SW but Alibre is supposed to be based on SW and here is how this Impeller was made. Granted it is just a Fun Model and probably won't work well but it might help a little. It includes the design tree. The PDF is too Large, sorry.