recycling clay scrapes with some cooking spray

[Stephen 437]

Ok I have been using cooking spray on some wood press molds and tossing the scrap because when  pressed the cooking spray is oozing out so the clay scrap is getting this on it. If I recycled any of these scrapes that seemed to be uncontaminated but had a little cooking spray I couldn't see would this blend into and mess up the clay or would it just burn out when fired? These are only quick prototypes and just tossing the clay is not that expensive but it just feels like a waste as it is a few pounds of clay when I press a run of them. 

[LeeU 1,117]

burns out

[Stephen 437]

Perfect! Thanks.

[JohnnyK 504]

 I wonder if the cooking spray reacts differently than WD-40? I use the WD-40 to lube my extruder before squirting clay. When I clean it out, there is some residue in the left-over clay and it is a real pain wedging it into a homogenous mass...

[neilestrick 3,564]

Oil will burn out in the bisque, but if there's enough of it in your clay it could affect the workability of the clay depending on how much was in it. I don't know how much it would take, but if it seems like it's working okay I wouldn't worry about it.

[Min 2,469]

57 minutes ago, JohnnyK said:

I use the WD-40 to lube my extruder before squirting clay. When I clean it out, there is some residue in the left-over clay and it is a real pain wedging it into a homogenous mass...

I can see if there is too much WD40 it could cause problems since it's a water displacement product. I know if I use too much WD40 on molds my porcelain cracks like crazy. 

[Bill Kielb 685]

1 hour ago, Min said:

I can see if there is too much WD40 it could cause problems since it's a water displacement product. I know if I use too much WD40 on molds my porcelain cracks like crazy. 

@Min- Makes total sense

One of my professors once told me oil is oil Bill. At the time we were discussing cooking oils and light oils such as kerosene. Anyway, years later I think he was right as my perception was cooking oils were so much safer. WD40 contains mineral oil and alkanes among others with an alkane  (Nonane)  that interferes with the bond with water in effect making WD40 water resistant or displacing. Pam is basically Canola oil among others and contains Lecithin and silicone to develop its' properties. Potters seem to have used them for so long it seems they are fairly harmless in small quantities. 

Both seem to work well at minimal levels. At elevated levels they both likely affect the workability of the product, with WD40 maybe having a lasting effect because of the Nonane component ……… maybe.

As others have  said, basically too much of anything is likely to have an adverse effect. I only use WD40 on my castable cement products, everything else is minimal Pam only when necessary.

[Stephen 437]

Thanks everyone!

I have trouble with knowing what is too much. A light spray didn't release well and heavy spray had too much excess. Hate  working with it at all, big mess. Doing another round today will attempt a light spray.

Although it saves a lot of time to just cut and run these for prototyping before doing a mold I might just ditch the wood altogether.

 

[Magnolia Mud Research 632]

consider using dryer clay and/or dusting the inside of the wood mould with dry calcined kaolin as a release agent. 

LT