Cams

[Brendan O' Regan]

I need to machine a cam from a drawing. Is there any c-hook or software compatible with mastercam to create it.

I have been given a number of points but i cannot use a spline as i have been told this will not be accurate enough.

Thanks in advance.

[Zero]

There is a raster to vector converter that you could try (on the mastercam site) by scanning the drawing into your computer, but I don't think that it would be as accurate as you need it to be.I don't know if the drawing was created on a cad program or not but if it was,I would try to see if you could track down some kind of file form that you could convert in mastercam?

[Brendan O' Regan]

The Drawing I have was created on CAD but seems to have gone missing and is not available on CAD any more

[Trevor Bailey]

Crower Cams, in San Diego, CA is a large CAM manufacturer that might be of some help to you. I do not have their number with me at this moment. They are a MC user, so this might be good place to start.

[Allan]

What would be more correct than the spline? They do not want the cam to be smooth and free flowing? You could create lines from point to point j/k.

How big is the data set?

Allan

[Scott Bond]

Hi

Draw what you have on the drawing.

Then try this------

from the create menu

spline/

curves/

chain/what you drew from the drawing

max.error -set to desired accuracy.

If all the information is on the print ,this will work.

[JAMMAN]

I do that all the time, Scott. I've noticed the "error" setting seems to have changed it's impact on the spline between V7 and V8. Anyone else notice this? Also in order to "trust" the geometry I analyze every other arc and re fillet. I can't see the need for more than about 10 arcs in cam geometry. Please correct me if I'm wrong.

[Chips Ahoy]

I do quite a few cams. I get the file in from engineering as an iges file and I take the geometry and use the c-hook "SQUASH" and that puts all of the geometry on the same plane. Then use the roll feature and roll this cam profile onto the radius you need the profile to be on. I don't have my notes so, hope this helps. Rick

[gmenzies]

we have a seat of cadkey we hardly use anymore. but we have a add on called powerpack. below is a qouted description of one of the functions that is avalable to me. if you like ,post the file to the ftp site. and I will do a cadl export out of

mastercam into cadkey and create your 2d profile.

and put it back on the ftp site for you.

Qouted from the help description

"This program creates Cycloid or Simple Harmonic (SHM) motion cams as closed 2D splines passing through points located on the cam profile.The program also calculates the absolute value of the maximum pressure angle and displays the roller in the corresponding position. The pressure angle is measured between the normal to the cam surface at the contact point and the direction of the roller movement. In general, this angle should be kept below 30 degrees. The program displays a warning message if anywhere along the cam contour the pressure angle exceeds 30 degrees. The minimum value for the cam base diameter above which the maximum pressure angle would drop below 30 degrees, is also calculated.