3d printing sand casting patterns

[DeltaCharlie]

Hi all, been busy learning how to make 3d patterns for metal sand casting. Just now getting to the point where I can design the part using FreeCAD and get it to slice using Cura without errors. Still having trouble getting all the draft set on complex shapes but I will keep working on it.

So far I made a small 3 inch flywheel for a model steam engine I want to build. It was a fun project and I learned a ton.

Anybody else messing around with making patterns?

Thanks, Dale

 

[benmychree]

I enjoy making patterns of WOOD, of all things! Don't need a computer or 3 D printer either---

 

[m1kemex]

I enjoy making patterns of WOOD, of all things! Don't need a computer or 3 D printer either---

You can CNC route patterns from wood.

 

[DeltaCharlie]

I enjoy making patterns of WOOD, of all things! Don't need a computer or 3 D printer either---

The idea of making the patterns out of wood did cross my mind but I wanted the challenge of trying to learn the computer CAD software and 3d printing. I also like mixing old and new technology.

Perhaps I should mix 3d printing with wood - wood PLA is available and it seems like it might make for a very good filament as it can be sanded and sealed like wood.

 

[DeltaCharlie]

Aluminum casting on the lathe. A bit surprised how little it took to clean up the rough surface. Will be working on improving my sand ramming to get a better casting but what the heck it's looking like a usable part.

 

[Ulma Doctor]

A little OT,
Some folks use the 3d printed part as a loss plastic piece and pour the molten metal directly into the cask through sprue holes without removing the plastic.
I have also heard of centrifugal wax casting too, where the wax is displaced by the molten metal in a centrifuge .
Both processes seem very interesting

 

[DeltaCharlie]

A little OT,
Some folks use the 3d printed part as a loss plastic piece and pour the molten metal directly into the cask through sprue holes without removing the plastic.
I have also heard of centrifugal wax casting too, where the wax is displaced by the molten metal in a centrifuge .
Both processes seem very interesting

I find all metal casting to be very interesting. Decided to try green sand casting as it's one of the oldest and does not cost too much to get started.

 

[rodm1]

Don't enjoy buy do it all day with foam.

 

[GrifterGuru]

A quick, but relevant, question. Did you go a percentage over size with the pattern to allow for shrinkage in the casting as most molten metals do shrink as theycool and solidify in the mold.

A quick example to look at is this. Not the be-all end-all and there are specific calculations based on material being cast, but it does give a rough idea...

https://www.novacast.co.uk/articles-library/metal-shrinkage-in-castings-and-why-it-matters/

 

[MrCrankyface]

I've played around a bit with printed patterns. Generally they can be a bit sensitive to getting squished together if you're packing sand, otherwise they're great at allowing high complexity with little effort.
I tend to plaster and paint them and use some wax to make them slippery.


Not very good job at gating/spruing but it worked.


And after some cleanup.