Frit-Happens !

Technical Forum => Search Tips and Techniques => Topic started by: shafeenan on March 31, 2015, 11:33:43 AM

Title: Clay moulds/molds - have you ever made your own?
Post by: shafeenan on March 31, 2015, 11:33:43 AM
I've just bought some nice smooth clay from a potter friend and want to make some moulds/molds.
Trouble is firing. I have an SC2 and wonder if anyone knows it it would fire hot enough to bake my moulds/molds?  And to what temps do you think I should go?
My chum bought the clay originally for someone else and hasn't used it herself so can't advise on a baking temperature!
Thanks for any help!
Title: Re: Clay moulds/molds - have you ever made your own?
Post by: Zeldazog on March 31, 2015, 01:37:04 PM
I think you've already thanked Terri for the information and firing schedule that she provided in another thread (about fibre board I think), which included rates and ramps, and ideal temperatures.  I think she also said bisque firing is pretty much the same for all clays.  From memory I think you can bisque fire terracotta clay a bit lower, as it is generally a lower firing clay anyway, but I presume it's a buff or grey clay as you don't mention it being terracotta/

Cannot remember what the SC2 goes to, but your instruction book should tell you.
Title: Re: Clay moulds/molds - have you ever made your own?
Post by: Pat from Canvey on March 31, 2015, 06:28:24 PM
I don't recommend it. I tried a mini pot melt in my SC2 just to see if I could. That was at 930 deg C. The door had to be lagged outside with ceramic fibre blanket to keep the heat in and the paint on the outside of the door became a fetching shade of grey. In the past I've fired ordinary grey clay to bisque at about 1000C in a bigger kiln. The pot melt did work but wasn't worth the effort in the SC2.
Title: Re: Clay moulds/molds - have you ever made your own?
Post by: shafeenan on April 01, 2015, 03:21:47 PM
Thanks for the feedback - even making the moulds seems to be more difficult than I'd realised - renewed respect for potters/ceramicists!
Title: Re: Clay moulds/molds - have you ever made your own?
Post by: silkworm on April 02, 2015, 09:29:19 AM
Hi, I'm very much in agreement with you on how difficult making the moulds is and how complicated the whole procedure is. I've been doing an introduction to casting class this year  and have really enjoyed it, it has been interesting to learn another technique and great to have a time that is just for experimenting, the bulk if the work is with clay and plaster not glass so it is messy in a very rewarding way. One of my aims was to learn to make my own slumping moulds but I now realise that there is way more to the process than I thought. I have no ceramics/pottery background so was completely clueless about clay, plaster etc or even about very basic things like the fact that most moulds are single use! 
For repeated use for stuff to sell I would probably now stick with commercial moulds - and appreciate why I pay so much for them!
My husband just bought me a book about it all 'Mould Making for Glass' by Angela Thwaites, packed with information, recipes etc, it might be worth seeing whether you get a copy of this.