Help - Creating Springback surfaces in Catia...???

[l3ob]

Our tooling group has the task of creating several 'Sprung' surfaces for composite tools. These 'Sprung' surfaces will compensate for the shrinking that happens during the curing process. We do it manually; but, it is time consuming and tediuos to get it accurately. These are not simple ruled surfaces either. Envision a surface of a Horse Saddle. If one were to lay-up this surface on a female tool (material on the inside of the tool surface) during the curing process, the material would draw in away from the tool, increasing the deviation as it moves away from the center-line. The resulting product would deviate from the true Horse Saddle surface to maybe .25"+ at the bottom side edges, being narrower than the original. Our tooling guys have to pain-stakingly create a tool surface that simulates this deviation from the original in the opposite direction, wider than original, so that when the material shrinks, it ends up at the engineered location. We are hoping that there is some 3rd party software or some Catia add-on license that will aid in analyzing the required deviation, based on the lay-up parameters, and creating these 'Sprung' Surfaces efficiently/quickly.

 

[CATlitter]

Take a look into GSO, last time I checked t was about $12-15,000 USD but from the sound of things your ROI wouldn't take long.

CATIA - Generative Shape Optimizer 2 (GSO) extends the wireframe and multiple surface creation features of CATIA - Generative Shape Design 2 (GSD) with powerful global deformation technologies. Based on exclusives smarts tools, CATIA - Generative Shape Optimizer 2 (GSO) allowing the user to deform shapes quickly and decreasing the time to complete the design process.

Jim

 

[Azrael]

As CATlitter suggest GSO module will give you access to the RSO (Realistic Shape Optimizer), which we use to reshape the part according to scan data.

There is one 3rd party software, a so called golden partner, i think it's called CATFORM, but that is for simulating sprung back effects from stamp procedures. I don't know if it could be used for your case.

 

[CATlitter]

Another CAA V5 based product that I am currently researching is called Dynavista Formability Shaper that can be purchased through Forming Technologies Inc. (forming.com) It has functions similar to those found in the Catia GSO workbench along with some others. Just another option you may want to look at?

Jim

 

[HGMorgan]

|30b,
You don't want 'springback' (or 'sprung') surfaces. Springback is used in forming tools like hydro-blocks where you overform a flange by some degree and it 'springs back' to the desired final position.

As you noted in your post, you want 'scale'. In the injection mold and composite tool industry, a scale factor of the part material is called out and that scale is applied to the tool so the finished part is the correct size.
Example:
1. Material called out shrinks .001 per 1"
2. Shrink factor would be .999
3. Scale factor for tool would be 1.001
You take the part and scale it 1.001, then make the tool off of that. When the part comes off the tool, it will have shrunk to the desired dimensions.
CATIA scale function is used for this.

Note: in some cases there will be a directional difference shrink, I.E., .005 shrink along X, .001 along Y, .0005 along Z.
CATIA may have that in one of the modules that I am not aware of, we do not have it in our MD2 configuration. We use our CAM software to do that type of scale.

 

[CATlitter]

HGMorgan

The command for "scaling" by different ratios in x,y, and z is Affinity. It's in the GSD product within the HD2 configuration and I'm almost positive Affinity is included in the GS1 product within the MD2 configuration. Check in the transformations toolbar or the Insert pull down menu under operations.

Jim

 

[l3ob]

Our tools already have a shrink factor of .99998. The Spring-back is yet another factor that is incorporated into our aircraft tooling depending upon the shape of the part. On parts as I described, a horse saddle, from the center-line to the extreme lower edges can be in the range of .25". Let me stress that this is separate from the 'shrink-factor'. However, in some cases, the affinity may work. The trouble with aircraft is not every tool lends itself to a convenient center plane for that sort of scaling. Example: a flange going around a curved deep channel shape. Both of these factors have been applied for years in composite tooling. It's just a pain and time consuming to accomplish. I have our Catia rep investigating the application of shape optimizer add-on licenses; but, we need to see a demo of exactly what we need before that becomes a solution. In the mean time, we are looking for other 3rd party softwares that may accomplish this.

 

[rizwa1n]

l3ob
i'm not sure if my reply has been posted so i'm posting it another time


try the link below

http://www.esi-group.com/Corporate/pam-talk/PAMTALK34_final.pdf

page 12 of 24

it mentions of a workbench that was integrated to Catia this year 2007. it helps to predict deformation in sheet metal design. this might be useful 'cause you can use the resultant surface to modify the tool used.

hope that helps
thanks
rizi