Lofting

[IronHorse]

How do i loft from bended surface? I have added the curve by projecting It to the surface? And shall cut down to the bottom.

 

I can´t indicate the lines for any kind of progress? I can´t use the original sketch since the lofting must start directly at the bended surface.

[Lazer]

Can you post a picture? I don't quite understand?

[IronHorse]

Hi!

You can see the green lines on the curved surface, these where projected from a sketch above it. I must loft directly from the surface otherwise if i do It from the plane the lofting starts to early. Which means the cut on the surface would be little to small... Difficult to explain :-)

[shift1313]

are you changing the shape as it goes up? what are you trying to get out of the part? I see a sketch below the green lines on the surface, are you lofting in this direction and subtracting? i cant see the sketch plane this projection came from but cant you simply loft to this plane since you are subtracting?

 

sorry i too am having a little trouble understanding what it is you are trying to do, sorry.

[IronHorse]

Hi!

 

As you see from first picture, my sketch lies little above the surface. My intention is to cut through the material down to the smaller sketch at the bottom. When you look at the second picture you see that the lofting cuts inside the green projected lines, this beacuse the lofting start before It reaches the surface. How to solve this I can nevet get

accurate result since the sketch is horisontal and the face curved..

[shift1313]

in your first picture. redefine your sketch plane to the point where it touches the surface of your part. This will get a much closer result.

 

the other thing you can do is you know the distance you are cutting out of the part so im sure you know your taper angle. you can make your sketch above the part oversized so that it meets your surface where it needs to.

 

Can i ask what this is for?

[IronHorse]

To lower the sketchplane to reach the surface at it´s closest point, is a beginning, and to oversize the sketch to compensate for the remaining flaw is also a possibility. I was thinking about that to, but It feels like a wrong way to do It? Can´t I use the projected sketch on the surface for something useful? I have tried to build rails etc. but with no sucess. This part is called "window" It´s used in shaft kilns, hand molded bricks, in fire resistance material.

[shift1313]

IronHorse, i wont have access to inventor again until tomorrow morning at work. I dont have 09 but i will play with it a bit and see what i can do and let you know.

[shift1313]

ironhorse. im using inventor10 and i dont have a command to project a sketch onto a plane(or at least not that i could find). the only way i was able to get the result you want is to loft between two sketchs(oversided one above the part) or use extrude and set a taper. Since you know where the bottom hole is and you can figure out the taper(if you dont already know) you can do this by drawing only one sketch. sorry i cant be of more help

[IronHorse]

Hi!

 

I followed your first suggestion to reproject the sketch at the top

of the part. By sketches at the sides I could easely calculate the

dimensions. When I loft It fall back to my original sketch :-)

 

Btw where are you from? I´m from Sweden

[shift1313]

Im in the USA, virginia.

 

So did it work correctly for you? I think inventor 11 has the option to project a sketch to a plan but i havent had the time to mess with it on there yet.

[IronHorse]

Yes now I achieved correct result. Thank´s for your help

P.s.

(hope your economy gets better) :-)