Creating molds from 3D Printing?

[sparkdaddychad]

Has anybody ever experimented with creating molds via 3D Printing and then pouring liquids into the mold to create the object? Kind of the inverse of what we traditionally think of when 3DP'ing.

[donny]

I've heard of people doing this to make metal objects. Since there is no reliable way of printing in Metal at home, people print plastic molds and then use those molds to make metal objects. Not the easiest or the best way, but it's definitely more affordable. than printing in Metal.

[sparkdaddychad]

Im going to give it a whirl. Im thinking that I can take my model, then create a box around it, then delete the model from the inside of the box which should then give me my mold. Only thing that i am worried about is overhang inside of the box being that I do not want any infill where the model previously was. Im guessing that I will also have to design some holes in the top/bottom of the mold in order to give me a place to pour the liquid into the mold and also to help with bubbles, etc.

I will report back what I find out, seems like a fun challenge to tackle.

[DangerousThing]

Look on the internet about lost wax molding.

i would, once I've gotten my object perfected, use a water-soluble filament that can be flushed out. Or you could use PLA and really heat the mold up to melt it out.

please keep us informed as to your progress. Maybe I'll need to make something in metal someday.

[jzatopa]

Here is a little on lost PLA casting

Here is a video of it being used in injection modling.



The same process would apply for something such as cast resin/plaster/cement molding except you might have to make larger pour holes and vibrate it to get the air bubbles out.

[IanJohnson]

3D printing is really good for making custom mold boxes. Model the thing you want molded built into the bottom of a cup which is shaped around the object with the walls only as far away as needed. Then fill the cup with silicone. Pull the silicone out and that's your mold. It uses only as much silicone as you need, rather than wasting a bunch filling up the corners of a square mold box. It's good for things you want to produce and would like to have many copies of the same mold. So print a mold that you will use to make molds. Some times you can pour and cure a mold faster than you can print one.

[dave21740]

I've thought about using food grade silicone to make a mold of a printed object, and use the mold to make chocolates. An actual chocolate printer would be more straightforward, but there's no way I can justify the cost. A mold would be a much cheaper entry to that sort of hobby.

[navkram]

I have done this a couple ways, I have printed the mold and cast that i have printed the part made a silicone mold off that Ã*nd cast parts, the problem is most parts it is not required for them to be cast solid, the resin material is not cheap, and weight is a factor.
I have made a small desktop rotational casting machine that will allow you to cast hollow resin parts. Check out the video http://rotomaak.com
I print prototype models for a large rotational plastic company this way i print one original make a mold and make reproduc5ions

[Valter]

Great topic.
I'd like to know if someone here are working with mold/cast resin from a 3d SLA printed scultures? Will resin models printed work fine to make a silicon mold and casting resin prodution? I'm thinking to sell my 3D characters models and I'm need more informations about process and method.
Should I print a 3D character or print a mold of the 3d character?

[navkram]

Great topic.
I'd like to know if someone here are working with mold/cast resin from a 3d SLA printed scultures? Will resin models printed work fine to make a silicon mold and casting resin prodution? I'm thinking to sell my 3D characters models and I'm need more informations about process and method.
Should I print a 3D character or print a mold of the 3d character?

Valter,
I have done both, if there is undercut detail in the figure you will have to go with a silicon mold pulled from a original, the reason for this is the silicon will allow you to be able to remove the part if there is alot of undercuts etc. it will stretch to be able to remove cast part. With a silicon mold you can re-use it many times and its pretty durable compared to a hard printed mold. If it is a simple (example hollow easter bunny) that has little detail like arms etc. you could print the mold, but with a printed mold it is rigid and have to think ahead on getting part out.
check out http://alumilite.com for some great mold tutorials.
the process is really dependent on the figure and end use. I have a model of a infants head from a customer that makes dolls, to cast this solid is not really feasible since the end product would weight around 5 pounds. so in this case my rotational casting machine fits perfectly to cast hollow parts. now the head weights ounces instead of pounds and functions perfectly for its intended use.

in short you should print the original vapor smooth or post process it however to get want you want and make a silicon mold of it.