Solid works to dwg translation problem

[Sarikahirpara]

Hi.....

I am modeling a roll in solid works and making a drawing of it and then i translate it into a DWG file. The problem is the hyperbolic profile of the roll is not getting translate properly, the point are shifting little bit here and there and hence when the dwg profile data is machined on CNC the roll is full of errors. Pls some one tell me the solution to get the exact profile in DWG format......

 

[Jboggs]

Have you tried DXF? Does it have the same errors?

 

[Sarikahirpara]

Yes it persists the same problem......i dont know why but i am not able to extract the exact profile coordinates of the hyperbolic profile. Every time i have to check it by machining and then i come to know that some portion of the profile has got error. Some times the half profile is perfect and we mirror it? But that can not be the solution.

 

[EEnd]

My suspicion is that the hyperbolic curve is being approximated by a sequence of lines or arcs in the DWG / DXF. Before you machine, you might be able to determine how well the approximation is by importing the DWG back into SW and comparing it to your original geometry. You might have better luck doing the translation to arcs yourself by tracing over the hyperbolic curve in SW using a sequence of arcs. The practicality of this approach will depend on the hyperbolic curve and your required accuracy in terms of position and curvature.

Eric

 

[AnnaWood]

Can your CNC machine interpret cutter paths for hyperbolic profiles or just lines and arcs?

Anna Wood
SW2015 SP5, Windows 7 x64

 

[Sarikahirpara]

Hello eric,
My profile is a continuous curve and in dwg also it shows a tangent continues spline curve. I have seen that in dwg when i select the curve it shows two differnt curves, one is my profile curve it self and one is the curve connecting the vortex points of the curve. Second thing is when i first open the dwg file curve is not smooth and then if i double click any of the vortex point it becomes smooth. Whats the reason vehind it. I am done with comparing back my curve in sw but its not correct. Is there any thing by which i can give my solid model data directly from sw to machine?

Hello anna,
My cnc can interpret hyperbolic profile, thats no issue.

I am still not able to understand how it is possible, that some times my half profile or some length of profile is perfectly translated and some portion is getting errors.

 

[SBaugh]

If you are exporting out a DWG/DXF from an actual SW drawing file, have you tried changing the "spline export" options, and/or the "end point merging". The only problem we ever have is the scale output. We use Sheet scale 1:1, but if the view is not using the sheet scale, then it comes out incorrect (wrong scale). All our files are exported out to DXF and translated into the laser software. We make all sorts of straight and contoured parts, but we have not seen anything like what your describing.

Scott Baugh, CSWP
Gryphon Environmental

http://www.2gryphon.com

"If it's not broke, Don't fix it!"

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