Metal casting shrink compensation???

[anchange]

Is there an easy way to compensate for metal casting shrink? Can I draw up my model / pattern to the desired size and then somehow increase volume by a specific percentage (around 10 – 5%) to compensate for shrinkage as the metal cools during casting?

I’m sure there has to be something to make this simple… but I’m only a casual Solidworks user so I’m unaware. Any help would be appreciated.

I’m planning on design a few pieces is Solidworks. CNCing them with a Tormach. And then using them as patterns for basic sand casting with a mostly aluminum based alloy.

Also is there an easy way to generate patterns / mold objects from a Solidworks part that I’ve already made? If someone could point me in the right direction on this or link me to a tutorial that would be awesome.

Thanks for the help, it’s appreciated!

 

[CorBlimeyLimey]

To compensate for shrinkage, model the finished part and then use the Scale tool from the Features toolbar.

"Also is there an easy way to generate patterns / mold objects from a Solidworks part that I've already made?"
Not sure what you mean?

 

[anchange]

Thanks CorBlimeyLimey!

Regard my second question - How do I make a part that is a negative of a part I've already designed? IE how do I make a 3D mold of a 3D part?

 

[CorBlimeyLimey]

That's a bit more involved. Check out the Mold Design in the Help and Tutorial sections.

 

[anchange]

lovely, thanks!

 

[ctopher]

Just curious, why would you want to model the shrinkage? Why not model the final product only?

Chris
SolidWorks/PDMWorks 08 3.1
AutoCAD 08; CATIA V5
ctopher's home (updated Aug 5, 2008)
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SolidWorks Legion

 

[Gurjjeet]

you can also use cavity command in Mold Tools, that will add shrinkage & create cavuty at the same time.

If it is a simple part(a flat parting line),Do not worry about all the steps in tutorial just model your die block, place component in the assembly in relation to die block & use this cavity command & you are set.

Remember both should be solid bodies.

Gud Luck

 

[anchange]

Awesome guys thanks!

 

[macduff]

Design for the final product as ctopher suggested, if your company doesn't have a foundry in-house. Does your company cast in-house? If you out sourcing the part to a foundry let them dictate the shrink factor. Every foundry will have a different calculation for shrink.

Colin Fitzpatrick (aka Macduff)
Mechanical Designer
Solidworks 2008 SP 4.0
Dell 490 XP Pro SP 2
Xeon CPU 3.00 GHz 3.00 GB of RAM
nVida Quadro FX 3450 512 MB
3D Connexion-SpaceExplorer

 

[anchange]

It's just me playing around more then anything else. I have a little propane furnace setup that I'm using. Surprisingly it works pretty decently.

Thanks for the tip though, that makes sense.

 

[macduff]

That's sounds like fun. Enjoy!

Colin Fitzpatrick (aka Macduff)
Mechanical Designer
Solidworks 2008 SP 4.0
Dell 490 XP Pro SP 2
Xeon CPU 3.00 GHz 3.00 GB of RAM
nVida Quadro FX 3450 512 MB
3D Connexion-SpaceExplorer

 

[Theophilus]

Anytime you make the cavity for tooling, though, you'll want your shrink rate figured into the part before creating the cavity. So for tooling, that's important. Otherwise, I leave all my parts at actual size.



Jeff Mowry

http://www.industrialdesignhaus.com

A people governed by fear cannot value freedom.