Continue to Site

Welcome to MCAD Central

Join our MCAD Central community forums, the largest resource for MCAD (Mechanical Computer-Aided Design) professionals, including files, forums, jobs, articles, calendar, and more.

Profiles from point sets

dept664

New member
Part of my job is to make metering plugs for gas flow (industrial valves). We get a point set from the engineer, clean it up and output a text file of the points which we then pull into Wildfire. We then generate a spline from the point set, which is easy in Wildfire. You just tell it "Whole Array" and it selects all of the points, then you pick ONE point and it generates a spline. This works great for the initial profile.


Then comes the CAM software that the shop uses, Esprit, which takes the spline and breaks it down into X number of points. The NC machines make the profile by making straight line segments between the points. So, for CORDAX (inspection) purposes our model has to have those straight line segments as well.


The only way we've found to recreate the profle using line segments is that after you've re-imported the Esprit point set, you have to manually pick each point in order to do a revolve of the profile. This is painful beyond words and makes my colon pucker.


Does anyone out there have a better way? Something more along the lines of the way you would do a spline?


Gary B - Woodward Governor
 
Have you tried different export settings out...iges, step?


On iges export in 2001 there was an option to just export curves and points, you might be able to layer the points and turn off that layer and just get your spline.


You are probably talking more about from Esprit which I am guessing you use for a wire edm
 
My problem is not with the spline. It's recreating the profile with straight line segments from the point set that Esprit puts out. For instance, the plug I'm working on today had 400+ points. To make that in straight line segments I have to do a revolve operation, manually pick each point as a reference, then manually put a line between each point (from point to point to point...).


The programmers use Esprit to program the turned parts. The plugs are hard-turned on a CNC machine. They take my first cut of the plug - done with a spline - and output a new point set that can be machined. My model has to match the way the machine turns it, which is straight line segments between the Esprit points, approximating the spline down to .0001 rise or less on the profile (that's why so many points). Otherwise it won't inspect correctly on the CORDAX.


Gary B
 
Sounds like you are needing to regenerate this from the posted file that the cam package outputs.


If they are in order and you have AutoCad available you could input the points into a VBA rountine to recreate the line, would take a little coding but not too much also MasterCam could do this too..... but I guessing you don't have access to either
 
OK dept664 While I am not sure why you guys are doing things the way you are. You can get curve through points to do what you want by using multiple rad instead of spline. Just enter a radius that gives you a straight line instead of curves. If you are you using WF 1 or later I can send you an example if you need it.



Edited by: administrator
 

Sponsor

Articles From 3DCAD World

Back
Top