Trimming Hardened Clay

[motox]

Hi forum,

I am a newbie who just started doing clay 2 weeks ago. I have had some good lessons learned so far. But I am struggling after my clay has hardened with massive shrinkage.

Before I go on, I am using Air-Dry clay. Which they say hardens to Earthenware.

I added more layers around the piece to keep the clay from breaking (lots of cracks) but I have some other problems. The shrinking of the piece made some extensions of the part lift up or sideways, away from original design. Which are now rock solid. 

I would like to somehow trim some of it out (a good amount). Sanding sound like it will take ages. I have also thought about doing a horizontal drill where I get the drill to touch it the piece horizontally and remove some?

Basically clueless here and would appreciate any help. 

 

TLDR: I want to trim a lot of hardened clay from a piece. Is there something that's the equivalent of Hyper Sanding to get rid of a lot of meat?

[lgusten]

I've not used the air dry clay.  But my recommendation is how ever you choose to remove some of the surface, wear a protective mask.  The dust you will generate is not good for the lungs.

[Benzine]

I have *never* used air dry clay, but I did a quick search, and it seems it can by rehydrated by soaking it in water. 

If that's true, I would imagine you can wrap some damp paper towels around your object, cover it in plastic to soften it back up. 

[Magnolia Mud Research]

I often trim bone dry clay by wiping the area to be trimmed with a wet sponge, and then scrap the surface with a trimming tool.  The wet area is kept small and shallow to prevent cracking.  Slow going, but after a some practice, a rhythm sets in and the wipe, scrape, wipe, scrape gets the job done.  I have no experience with Air-dry clay bodies, but expect the technique would work.  

LT

[oldlady]

motox,  never touched air dry clay but it's name suggests that you must make everything perfectly the first time or lose it.   shrinkage happens with real clay too but this sounds really bad.

have you considered real clay?  is the problem that you do not have a way to fire real clay?    are you interested in becoming a potter or just trying to make one thing?

[motox]

Hi everyone

Sorry for the late reply. I live in Australia, timing is upside down

Thanks to everyone who replied. 

Thanks Benzine and Magnolia Mud Research:  I will try the damping method and reshaping. I thought the clay is set for good once dry. That's very good information to know.

@oldlady Thanks for the input. I haven't considered real clay. One problem is not having access to fire it, and also will be hard to move the object for me. The reason I got into pottery is because I want to make a motorbike fairing model. So pottery is kind of the means to get to a goal for me. If this works, then I will be making more models out of clay. Otherwise I might have to change method and try something else. 

 

[GEP]

@motox you might want to try oil-based clay, otherwise known as “modeling clay.” Rather than air-dry clay or the water-based clays that need to be fired. Oil-based clay is used by sculptors. It doesn’t dry or shrink. It hardens when exposed to air or when it gets cold, but it can always be softened up again by warming it, 

I don’t know much about making fairing models, but the car industry still sculpts car models using oil-based clay. 

[motox]

Hi GEP

Thanks for your input. I didn't know about all these different clay types. Might give modelling clay a try.

Regards

[Fred Sweet]

motox-

Some oil-based clays will be called plasticine, instead of modeling clay. One popular brand is Plastilina.

Regards,

Fred

[JohnnyK]

Have you thought of using fiberglass, resin and Bondo (body filler)? I rebuilt a riding lawn mower motor housing using body filler and window screen wire. You might also consider plaster to make the mold for the fairing for your motorbike...