Help! How to CAD model the transmission housing using Core and cavity method?

[kar0]

Hi all,
I am unable to find an idea on how to model this housing using Parametric Core and cavity method in NX, like inner and outer core. Can somebody provide me the general idea/framework in how to model this? I dont know where to start.

 

[CADMan_Jamie]

Hi Take a look at the attached.

 

[CWB1]

I'm a bit rusty in NX bc its been a few years, but in Creo I'd start with a pair of solid blocks the size/shape of the core boxes and "remove" your bellhousing model from the cope&drag to get the basic shape, then modify as needed.

 

[kar0]

Hi Take a look at the attached.

Thanks for the information, but how to construct the model parametrically, like building it from internal core and external core.Can anybody give idea

 

[CADMan_Jamie]

Easiest way is to Build a box around the entire bellhousing. Subtract out the shape. That will leave you with 2 bodies the core side and cavity side. I don't think there is any way to get the model parametrically. (Example: Cavity and core with drafts, holes, extrudes and sketches.) You would need to create these from scratch.

 

[CWB1]

I'm not sure what you're trying to accomplish.

If you're designing molds for casting, subtract the part from the sand then modify as needed to tweak draft angles, parting lines, and other features. If you try to model every hole, boss, and other detail yourself then your model wont match the part designer's, there will be a ton of variation stacking up. That's the reason shops ask for both a model and print today - to ensure customers get exactly what they want.

If you're designing a bell housing from scratch then 1. position the engine, transmission, flywheel/pressure plate/clutch/etc based on functional requirements, 2. extrude the engine and trans flanges, 3. quilt between the two flanges, and 4. modify as needed to strengthen, add fastener bosses, accommodate starter positioning, etc.

 

[kar0]

I'm not sure what you're trying to accomplish.

If you're designing molds for casting, subtract the part from the sand then modify as needed to tweak draft angles, parting lines, and other features. If you try to model every hole, boss, and other detail yourself then your model wont match the part designer's, there will be a ton of variation stacking up. That's the reason shops ask for both a model and print today - to ensure customers get exactly what they want.

If you're designing a bell housing from scratch then 1. position the engine, transmission, flywheel/pressure plate/clutch/etc based on functional requirements, 2. extrude the engine and trans flanges, 3. quilt between the two flanges, and 4. modify as needed to strengthen, add fastener bosses, accommodate starter positioning, etc.

Exactly, i want to design these bellhousing parametrically from scratch, but i cant even get the idea of how to get the basic housing shape without bosses,machined holes etc.Please provide some resources or information regarding how to achieve that shape in CAD. i am unable to figure out that.

 

[3DDave]

It's going to require experience creating variable section features. Read the manual and look on the internet to find how to make lofted surfaces in NX.

Example:

 

[CADMan_Jamie]

Hello, Take a look at this video.