creating structurally sound face sculpture

[Araceli]

Hello everyone.

I'm new to sculpting, zero experience. I made several faces/masks which I plan to use in a mosaic. I made two faces and they lacked the details necessary to make them compelling, so I read through Portrait Sculpting by Faraut and started my adventure into sculpting. The techniques demonstrated in the book greatly enriched the third face I made.

My process:

I created a paper base from newspaper,  added a layer of clay for the base and used this as the skeletal foundation, as a result the face/mask is hollow. From there I used some of the techniques outlined in the book, like adding the socket and eyeballs, then laying the skin over that. Adding muscle tissue and fat pockets. In short it greatly improved the final result: she was beautiful. I left everything to dry for about 3 weeks with a plastic bag. Each of the  faces were about 8"x6" and 1/2" thick. I  fired up my kiln cress FX23p kiln for the first time and filled it up with all three faces, a torso... it was packed. This was my first bisque firing.

Every single piece turned out great except for the one piece I really cared about: the third face.  I loved every effect I had created in the face and to my delight the burnishing  turned out even more beautiful than I had hoped.  Sadly,   the nose  in the third face "exploded". But the first two faces I had created were fine. So I did something different in the third face that lead to the explosion.   Before I attempt to recreate the face using the techniques I learned, I want to understand what I did wrong with the nose.

Can I  get some tips on what are some "best practices" to prevent these types of problems in the future? The following are my observations and concerns:

• The nose was about an inch thick, so I think that was part of the problem.
• I did not hollow the nose from the back of the sculpture. Should I have hollowed out the back or at the very least put holes in the interior of the mask of the nose?   
• Also, although I didn't have problems with the eyes, I'm thinking that just may have been sheer luck. As mentioned earlier,  I created the skull with sockets, literally made eye balls, then laid the "skin" over the entire sculpture, which had a fantastic effect. But I'm wondering if air could get trapped and become an issue in the future?  How can I prevent this?
•  Another concern is that  as I build up the face I'm adding small pieces here and there like building up the lips... Obviously there is some drying since I'm slow and it takes  me time to sculpt: a few hours.  I'm wondering if there is anything I should watch out for when applying these small pieces (aka could this cause air bubbles?)
• I don't particularly like using newspaper as the base? what other options do you recommend?
• And last: for the mosaic, I don't want it to be heavy, so I was thinking of using styrofoam ( I know, not environmentally friendly :( ) and then apply grout to that to use it as a foundation. Any ideas on wether or not this technique is ok, any concerns/other options? The mosaic will not be  not be hung outside.

Thanks in advance!

 

 

 

[Pres]

Welcome to the forum Araceli,

 

As to your problem with the sculpture:

• The nose was about an inch thick, so I think that was part of the problem. Probably needed to be hollowed out. May be done later from inside, or use a cupped piece added on over a hole in face. This allows for modeling nose, but cuts thickness.
• I did not hollow the nose from the back of the sculpture. Should I have hollowed out the back or at the very least put holes in the interior of the mask of the nose?   See above
• Also, although I didn't have problems with the eyes, I'm thinking that just may have been sheer luck. As mentioned earlier,  I created the skull with sockets, literally made eye balls, then laid the "skin" over the entire sculpture, which had a fantastic effect. But I'm wondering if air could get trapped and become an issue in the future?  How can I prevent this? Same effect may be completed by making eye socket not as deep, then using eyeball shape cut in half for both eyes allowing less build up of clay in the eye areas. You have good technique here, as eyes should be assembled as layers with eye ball, lids, details added in sequence.
•  Another concern is that  as I build up the face I'm adding small pieces here and there like building up the lips... Obviously there is some drying since I'm slow and it takes  me time to sculpt: a few hours.  I'm wondering if there is anything I should watch out for when applying these small pieces (aka could this cause air bubbles?) If the clay seems to get to dry, use a little slip or Magic water to join new areas.
• I don't particularly like using newspaper as the base? what other options do you recommend? News paper works well, but some have used plastic bags filled with shredded paper as a base, vermiculite or pearlite in a bag will also work. Anything that may be shaped will work that way for a rough foundation. If you wish to get more in depth try casting a plaster form as a base, then cut the head in half if full, and remove from the form. More extensive, but if doing a lot of heads. . .efficient.
• And last: for the mosaic, I don't want it to be heavy, so I was thinking of using styrofoam ( I know, not environmentally friendly ) and then apply grout to that to use it as a foundation. Any ideas on wether or not this technique is ok, any concerns/other options? The mosaic will not be  not be hung outside. Good ideas, some others may horn in with other suggestions.

best,

Pres

[yappystudent]

2 hours ago, Araceli said:

And last: for the mosaic, I don't want it to be heavy, so I was thinking of using styrofoam ( I know, not environmentally friendly ) and then apply grout to that to use it as a foundation. Any ideas on wether or not this technique is ok, any concerns/other options? The mosaic will not be  not be hung outside.

I think it depends on how big and thick you're making the mosaic. Plywood is frequently used by mosaic artists with mosaics used strictly indoors. A product called Wedi board (about $30 for a 2'*4' sheet, it's pricey) is lightweight and designed for custom tile backings in showers and such. Some artists just use tile mesh, if you can find it, you don't even strictly need a rigid backing as the grout forms a single rigid form in most cases. I think the weight of the mosaic is going to rip the styrofoam, and I suspect there may be other issues like how to attach the mosaic to it, and how in turn to attach the styrofoam to the wall or w/e you're going to place it on.

[preeta]

Areceli were you just going to use the styrofoam as backing to set up on but not hang? Grout is not enough to hold pieces together. The object of grout is beauty and fill in the gaps. 

If weight is concerned I’d make tiles from scratch instead of mosaics. 

But to hang and be safe you definitely need a backing to give it a long life. Which does make it heavy.   With grout I think of mural.  

[Chilly]

Clay usually explodes because it is not dry, not because of air pockets.

So, yes, the nose was probably too thick.  Although you let it dry for 3 weeks, the problem is that as the outside layer of clay dries, it shrinks.  It then forms a crust, which makes it harder for moisture to evaporate from the centre of the thick piece of clay.  It might have fully dried if you''d left if for weeks and weeks, but then again, it might not.  I made a tennis-sized ball of clay, hollow, but fully sealed.  I left it for months, and when I broke it open, it was still not fully dry inside.

[Benzine]

In regards to the nose exploding, as other have suggested, you could just hollow it out from the back, or what I usually do is remove quite a bit from inside the nose, as I am doing the nostrils.   

In either case, this will allow it to dry quicker, and more evenly, and greatly reduce the odds it will explode, from the moisture.

[Denice]

I use to do life size portraits from the waist up,  it takes some practice but  hollowing out is the key.    I tried to keep a consistent thickness on the walls of the clay,  some areas like the nose  I would take a needle tool and  poke some holes to help it dry evenly.   If you poke through you can easily smooth it over.   If you decide to go into larger sculptures I can give you a list of books that might help.    Denice