How do I draw a variable torus?

[jpwmartin]

How would one create a "variable" torus?  Not sure if that is the right word for it... what I need is a torus that is on one side a diameter of 10mm and then increases in diameter to 62mm on the other side, and then decreases back down again to become the 10mm on the first side.  Tried to create a solid using sweeping and lofting but couldn't come up with the right result.   Anyone know how to do this?

[Müřlıń®]

you sweep it..

[crazy^millman]

Going to need it break it up. Sweep one side from 10mm to the 62 mm then make the other side the 62mm down to 10mm. I think trying to go from small to big and then back down to small is asking too much of Mastercam. Got a sample of what you are trying to accomplish?

[jpwmartin]

I am actually going to use this to create a negative of it on the OD of a 11" diameter round part using Boolean remove.  Then I have to figure out how to machine it on a 4 axis machine.

 

[Müřlıń®]

I was wrong Sweep will not give you what you want.

Here is a net surf solid that is close.

 

I used linear math to come up with cross sections and as you can tell the the blend is a little off.

Depending on how accurate you need your shape, this will call for a Fractional logarithmic spiral equation to come up with your 

Sectional geometry for Mastercam to make a perfect blend.

There might be other softwares you can use a blend and stretch feature to smooth out the transitions.

If I messed with it a little more I could just manually adjust the section arcs and get it with very little error by eyeball.

 

 

torus.mcam

[Günther Massimo - GMCCS]

You can sweep a solid in 2018.

In 2018 you can assign a guide chain.

[Müřlıń®]

2 hours ago, Günther Massimo - GMCCS said:

You can sweep a solid in 2018.

In 2018 you can assign a guide chain.

Oh that is awesome.....that guide chain was the missing link on sweep in 2017.

No need for math on that one

I tried a couple different ways to sweep it but the control was not there and there was distortion....

But I was sweeping it from center and not from outside.....

 

Mastercam getting better all the time...

[jpwmartin]

I am using x9, do you think there is a way you could save that shape in a certain format so that I could open it in x9?  And the center diameter has to be 11.902"

 

[#Rekd™]

A lot of members here are contract CAD/CAM guys. If you are willing to pay someone I am sure they will make your model.

Looks like a cool project!

[AMCNitro]

I dont know why you guys are making it so complicated.  Granted its a simple one, it goes from 1" to 2", which makes the transitions easy to calculate(2 to 1.75 to 1.5 to 1.25 to 1, and then back again).  I just created the circles for the torus, then used 3 point circle to create the sections, and then I created the surfaces using net surface.

[Müřlıń®]

10 hours ago, AMCNitro said:

I dont know why you guys are making it so complicated.  Granted its a simple one, it goes from 1" to 2", which makes the transitions easy to calculate(2 to 1.75 to 1.5 to 1.25 to 1, and then back again).  I just created the circles for the torus, then used 3 point circle to create the sections, and then I created the surfaces using net surface.

I tried this in X5 and it worked easily what am I missing in 2017?

 

I think it is because I didnt go around in a circle but did half at a time.

 

YEP...that is what it was.

You cannot do this half at a time you must do a loft and sweep around a full circle and Mastercam NURBS will blend the the inside and outside properly.

It really is easy like Nitro says...just have to do the right steps.

 

 

 

 

lofting in a complete circle will give very good results...

 

but it's still not perfect look at the next pic and notice the bulges in the floor...the need for another influencing curve is apparent.

Can't wait to try 2018.