trim sur help

[Rakesh]

Hi every body

I am doing Trim sur to circle,use Normal projection exercise from mastercam handbook vol 2.

I am getting the warning " Cannot Trim Surface,Selected curves do not form a closed boundry".

I using the step as: surface-trim sur to curve-selected the sur-enter-selected the circle curve-normal icon is pressed (but there is .1 value and I leave it as it)-indicate area to keep and slide the location. When I do this it give the warning

If anybody help me what I am doing wrong

thanks in advance

[Colin Gilchrist]

Rakesh,

 

It looks like a bug in X2. If you do the exercise and use the "view" button instead of the "normal" button, it works. As a work around you can do this:

 

Use Xform - Project to project the circle onto the surface. Select the "normal" option in the Project dialog box. Mastercam creates the projected curve on the surface. Now do Surface - Trim to Curves, select the curve on the surface. Slide your arrow outside of the curve and press enter. Then it will work.

 

HTH,

[Colin Gilchrist]

Rakesh,

 

If you still can not trim to the projected curve, try running RAM saver after you finish the Normal Projection using Xform. There is definitly something fishy going on...

[Rakesh]

Hi Colin

Thanks for your reply.

Now I did the same what you mention by projecting the curve normal to surface and than used the view option and get the trim surface.

Than I compare this trim surface with the other situation like: not projecting the curve on the surface but using the view option and got the trim surface.

this trim sur should be little different than first situation but it is same.

If you have any idea.

Any input will be apprciated

thanks

[Colin Gilchrist]

When you do the projection through Xform - Project, you need to select the surface button in the dialog box, pick the surface, then press the "normal" button on the Project dialog box.

 

You should see the shape of the circle change to what looks more like an elipse in the graphics window. You should be able to switch between "view" and "normal" in the Xform dialog box, not in the Trim - surface to curve ribbon bar.

 

As you switch between view and normal, Mastercam will update the shape of the projected curve while the dialog box is still open. This is a seperate step from the trim command. Do the "normal projection" first with Xform, then trim the surface to the curve.

 

 

HTH,

[Rakesh]

Colin

You are right I did not select the normal in the x-form.

Now it is doing everything right.

Thanks for all the informations.

[Rakesh]

Hi everybody

I am trying to learn trimsurface, surface-curve-normal.

I did x-form-surface-normal stuff and did trim sur normal to the surface. My concern is, I got the trim surface but the hole is ellipse, how we can trim curve surface and get the complete round hole shape on the surface.

Any thought will be apprciated.

thanks

 

[Rakesh]

Do I need to clear my question more or it is just a friday night

[Colin Gilchrist]

Hi Rakesh,

 

When you do a curve project you have two options, the first is "view" which really means construction plane. The second is "normal" which means that the curve is projected down onto the surface using the tangent vectors of that surface.

 

Using the last example that you posted if you change the trim options to "view" you would get round looking holes, but only when you look at the surface in top view.

 

What you need to do is create your arc normal to the surface, then do the projection in that arc's view.

 

For a quick example do this:

 

Create a point on the surface using Create - Point - Dynamic. Sketch a point in the middle of your surface somewhere.

 

Now use Xform - Project, select the point, and choose the "surface" projection option. In the Surface projection area enable "normal", then the "Points/Lines" button and click on it. Then set the line length to 1". Press the flip button if necessary so your line points up and away from the surface at a normal vector.

 

Now that you have the line that is normal, go to the "Planes" menu and select "Planes by Geometry". In the graphics window click on your line and then press enter. You will get a Cplane icon showing you the new plane you are going to create. X and Y direction doesn't matter for this example, just make sure Z positive points away from the surface. Save the Cplane. Now with that plane set as your current construction plane, create an arc. This arc will now be "normal" to the surface. Then you can project the arc using "View" and the cut in the surface should look like a regular hole.

 

HTH,

[Rakesh]

Colin

Thanks for writing in detail and I appreciate your patience.

I draw the line approx 1 inch normal and when I go for plane by geom and select the first normal line, It ask for the second line. I guess I should draw a line prep to the normal line before selecting the plane by geom. Do I missing some thing now.

[Rakesh]

Colin

I have a point and one normal line on the surface

I am trying to use diff way to use that normal line to crate a plane so the z axis will point outward but I could not, I am missing some thing.

Any thought guys.

thanks

[Colin Gilchrist]

Rakesh,

 

My mistake! You need to use the "Planes by Normal" command, not "Planes by Geometry". It should work much better now.

[Rakesh]

Colin

Thanks I got it now.

You are genius, thanks again

[Colin Gilchrist]

I'm happy to help Rakesh. Lord knows I've gotten my fair share of information off the forum.

 

 

P.S. One of the best tools for learning Mastercam is the context sensitive help files. I'm probably about 70% self taught in Mastercam. That all comes from reading the field definitions of all of the different dialog box options and reading the reference guide front to back.