Surface-to-surface tangent mate?
Surface-to-surface tangent mate?
(OP)
Does anyone know if it's possible to mate two surfaces as tangent if both surfaces are irregular? I have an IGES file of an air foil I'm importing (irregular) and I need to make a fixture assembly to do some work on it. I'd like contacts to the air foil at particular points (for maximized accuracy) with a revolved part (similar to a tire).
I haven't figured out how to do this in SW2001+. Can it be done in 2003?
I haven't figured out how to do this in SW2001+. Can it be done in 2003?
Jeff Mowry
DesignHaus Industrial Design
http://www.designhaus-i-d.com






RE: Surface-to-surface tangent mate?
I am not sure if this is what you want or not, but you can make any cylindrical part tangent to a completely enclosed surface like a slot. This was one of the mates added in 2001 Plus.
I just made 2 parts. The first was a rectangle with 1 side changed to a construction line. I added 2 lines to make a point and then added a 1" radius to all of the corners and extruded. The second was a revolved box (like your wheel).
In the assembly, I added a mate so that both parts were on the same plane. Then I selected all of the inner surfaces on the pointed box and the outside of the wheel and hit mate. Make sure you do a preview because invariably the wheel will want to mate backwards to what you want.
Selecting Move allows the wheel to appear to roll around the pointed track.
RE: Surface-to-surface tangent mate?
I forgot to mention that the first mate is important. SW will generate an error if you try to add the second mate first, at least it will if it has to change the orientation of the wheel.
The mate that is created is called a CamMateTangent.
RE: Surface-to-surface tangent mate?
Thanks for the tip on the Cam Mate Tangent. I'll try it out. Do you know if this is limited to cylindrical surfaces to something straight (flat)?
In my case, one surface is the compound/irregular surface of an air foil and the other is essentially a revolved circle. This way, the contact between the two parts will be made at a single, calculated point (predictable and precise).
If there is no way to mate these, perhaps I can position my fixture "tires" generally where I want them, then collide them into the air foil and maintain their position at the collision point. Anyone know if this will yield accurate results if I have SW stop the movement at the collision point?
Thanks for the help.
Jeff Mowry
DesignHaus Industrial Design
http://www.designhaus-i-d.com
RE: Surface-to-surface tangent mate?
I think it is limited to cylindrical surfaces (or cams) to a flat path. However, I don’t think that should be a limitation for you.
I may be all wet here, but you could add a plane in your assembly and extrude a profile where your air foil crosses it. Make the extrusion nice and large in the first place so that you can easily select all of the surfaces. Make your wheel flat instead of round but add a controlling dimension for it’s width. After the Cam Mate is added and the wheel is rolling around like you want, change the width of the extrusion to .0001 and do the same thing with the wheel. It may not be a point but it is awfully close.
RE: Surface-to-surface tangent mate?
1.)use 3Dsketch to place a point at the desired location of tangency on the surface.
2.)place an axis thru the point and normal to the surface.
3.)place a datum plane thru the point and normal to the axis
RE: Surface-to-surface tangent mate?
RE: Surface-to-surface tangent mate?
I just went back and reread this entire thread. The Cam Mate Tangent idea would allow you to view your tool but it would not provide you with a path for the tool to follow. I do too much Scan reading, sorry.
Wouldn’t a simple sketch offset provide you with the tool path that you need?
RE: Surface-to-surface tangent mate?
From what I can tell (haven't tried it yet), TheTick probably nailed the solution to my intended need. My fixture/jig needs to make contact tangent to the air foil surface at several specified points, but sketch cross sections always yield splines--and though I may be able to find tangency to the spline in 2D, I truly need tangency to the surface in 3D at my specified point. The axis/plane trick will probably allow this. Thanks! I didn't know about axis orientation of this sort before and therefore wouldn't have considered using an axis for this purpose.
Jeff Mowry
DesignHaus Industrial Design
http://www.designhaus-i-d.com