Casting an impeller from a 3d print

Hi all,

I'm wondering if with Moldlay filiment I'd be able to print and cast this...

Attachment 10136
From http://www.thingiverse.com/thing:13188

I'm new to printing (and this fourm), so is it possible to print this with a wax like filament, and then cast it using lost-wax method?

Can I cast it with normal (hollow) pla?

If it works great, if not why? Also, I have access to the Ultimaker 2 plus and the Makerbot (2?) through my school.

The reason to be metal is because its going to spin at 6000-9000 rpm, so I don't want it to disintegrate and destroy the casing (I have limited prints AND it would be cool :) ) Don't worry about safety, It'll be shrouded in steel.


Thanks all,

James

It seems doubtful; looking at the FAQs on the Matterhacker site https://www.matterhackers.com/store/...GICAgObZqrYKDA they talk about it melting and running out of the mold, but not about it burning out cleanly. It seems that they had other sorts of molds in mind when they developed this material.

I have heard about people having success in burning out regular PLA, though. I'd use Plasticast investment, which resists the expansion of plastics when heated, and goes to a higher temperature, burn it out hotter and longer than an equivalent wax part, and introduce a little air to the kiln at the end of burnout to help combust any residues.

Andrew Werby
Juxtamorph.com

As Awerby mentioned, melt out is not a very great idea for casting. It can work for some basic geometries but can be rather limited for anything that prevents gravity from evacuating the wax.


We produce a machinable wax filament that is specifically engineered for investment casting. If you are used to printing with typical plastics, it can be tricky to learn, but the advantage comes from the very easy post-processing and extremely low ash content.

I have actually done a cast personally a few months ago with an impeller similar to the one you linked. This was only my second time doing this, so it is admittedly not a very good cast, but still a proof of concept for that type of print geometry. Far from a polish here, just some passes with a Dremel and sandstones.
http://i.imgur.com/11MBFnK.jpg

Someone with more experience casting did this model for us that we printed at 50 micron, then polished with mineral spirits.
http://i.imgur.com/g73AaEF.jpg