Parametric vessel update 2

This is another update for my parametric vessel. The printing and mold making were covered in previous posts. This one will cover the slip casting process and alterations of the form.

I did try fixing the render for the image above, but I must be doing something wrong without knowing it. Apparently baking my object from Grasshopper and trying to put a different material on it in Rhino creates this mass up abomination. Kind of looks like the marbling technique that is sometimes used in ceramics by combining two clays, but not wedging them fully together. Though it may be two bakes on top of each other...

Anyways...

If you have read my previous two blog posts on this particular vessel, you would know that I struggled with getting it even printed and looking nice. The plaster mold making for the most part wasn't any trouble other than the breaking of the acrylic plate. 

After I removed my 3D printed form from the mold, I let it dry for a couple of days. It's good to do so because the wetter the mold, the more time it takes for the moisture to be pulled from the slip and into the plaster.

After the mold is fully dry, it is good to give the mold a little spritz of water before casting depending on how long the plaster has been sitting without use, so it starts the capillary action and reactivates the mold. Then the elastics are added to hold the mold together and the slip is blunged to activate the slip and homogenize any settled particles.

Make sure to sieve the slip to remove any large chunks that could jeopardize the structures of your slip model. Then pour the slip slowly until the slip reaches the top and make sure to top up regularly to prevent the sides of your pieces to be different.  

Then comes the waiting game of babysitting. Yippee....

When the layer thickness is to how you want it, slowly pour out the slip back into the bucket through the sieve. Just in case any random blobs of slip try to leap back into the bucket. Make sure not to cause your slip to glug out of the mold because it has the potential to pull your model from the sides of the mold. When the slip has stopped draining, set your mold upside down on an angle to prevent a stalactite on the bottom of your model, and to allow air flow. 

Then once again, it's the waiting game. Wait until the sides of your slip model look to be pulling away from the mold by themselves before considering opening your mold. If the model doesn't immediately release, give it some more time to dry. You can also try giving the mold a little smack on the backside to get the plaster to release the model. Be warned that it may cause some deformation when the model is caught depending on the stiffness of the slip. You just have to be careful. 

And there's your model ready to be altered.

I did have some difficulty deciding how I should alter the form to make something more. What I ended up doing was cutting it in half and making two small cups from the bottom half of two models. I slip casted a model and cut it in half before putting some slip on a plaster cookie before putting the end in the slip on the cookie to cap it off. Once the slip dried enough, it is easy to pull the form off of the plaster, cut the rim in the top, and smooth down the seams while another model is being slip casted. Once the model was ready, the steps were repeated to make another cup. 

I am not sure as to what to do with the top halves of the models. 

All in all, this process was rather easy to do. The model had no troubles being cast which is really nice. The only thing that I can say that I would do differently is to do away with the model half and just build up clay around the full model before casting half of the mold. It would take more time to make sure that there would be no undercuts, but one could put a seam line (in Rhino) in the mold where it would be cut in half to make it easier to build clay around the model.