Frit-Happens !

Fusing and Stained Glass Tips and FAQ's => Fusing Tips and FAQ's => Tools & Equipment => Topic started by: Sandera on October 02, 2012, 07:31:26 AM

Title: Heavy items
Post by: Sandera on October 02, 2012, 07:31:26 AM
I'm not sure whether I've posted this in the right place but here goes.

I want to do some glass casting but need to find a supplier of plaster and flint that is either within driving distance to Yorkshire or who has a reasonable postage rate. Unless anyone lives in the area and is willing to share an order and postage? I keep finding sites that are very reasonable but once you add the postage on it becomes expensive.
:-\
Title: Re: Heavy items
Post by: Zeldazog on October 02, 2012, 09:53:30 AM
I've only found flint at pottery suppliers or I used to buy mine directly from the college or university when I was at each.

Have you tried googling for pottery suppliers in Yorkshire?  I am sure they're not all in Stoke  ;) ;)

Pottery suppliers will call it Potters Plaster - but you can also get it from some builders merchants, known as fine casting plaster - I recently bought a bag from a merchants in Nottingham and it was £9 for 25kg....

I found a lot of websites were lacking in information about items they sell, and also what they call it - like the plaster, flint is known by other names but I am afraid it escapes me at the moment, but try searching particularly US or Australian glass or ceramics information sites and it should come up.

HTH
Title: Re: Heavy items
Post by: Glyn Burton on October 02, 2012, 06:48:37 PM
Try CTM potters suppliers of Doncaster, I can't remember if they call it flint or silica flour in the catalogue but its the same thing.
Title: Re: Heavy items
Post by: Flyingcheesetoastie on October 02, 2012, 08:22:11 PM
I've found you can't get flint anymore due to the high silica content so my supplier has substituted it for silica flour.  The main difference is you have to amend the amount of water you use in your mix as flint usually comes in a damp form, i.e. with extra water and silica flour is dry and finer too.

Remember your dust masks and extraction too peeps, this stuff will kill you over time!
Title: Re: Heavy items
Post by: Zeldazog on October 02, 2012, 08:33:28 PM
Quote from: Glyn Burton on October 02, 2012, 06:48:37 PM
Try CTM potters suppliers of Doncaster, I can't remember if they call it flint or silica flour in the catalogue but its the same thing.

Ah, that's it Glyn, I was thinking Silica Sand but knew that wasn't right.
Title: Re: Heavy items
Post by: qwirkyglass on October 02, 2012, 09:14:23 PM
If its any help, in uni we use Fine casting plaster, and powdered quartz for our casting moulds. But im not sure where from.
Have you tried suppliers like tiranti?

can i ask what the flint is used for? is it the same as the quartz?
Title: Re: Heavy items
Post by: Flyingcheesetoastie on October 02, 2012, 11:37:27 PM
I'm sure most pottery suppliers will do fine casting plaster as well as flint.  But yes you will pay a pallet charge for delivery because of the nature of the material as this limits the carriers that will take it.  Also you'll find the amounts tend to be quite hefty, 25kg etc.

If you are sure making small molds or having a go, you can get small amounts (1kg etc) from Bath Potters - http://www.bathpotters.co.uk/raw-materials/c87

Title: Re: Heavy items
Post by: Sandera on October 03, 2012, 07:03:14 AM
Quote from: qwirkyglass on October 02, 2012, 09:14:23 PM
If its any help, in uni we use Fine casting plaster, and powdered quartz for our casting moulds. But im not sure where from.
Have you tried suppliers like tiranti?

can i ask what the flint is used for? is it the same as the quartz?

When I did a short casting course at Sunderland we used a mix of plaster and molochite (sp?). I don't know the technical details but the addition of flint or similar must have an impact on the viability of the cast so that it withstands the kiln temperature. I'm 100% sure someone on the forum will know and I'd be interested in finding out the why's and wherefores as well.
Title: Re: Heavy items
Post by: Moreton on October 03, 2012, 08:29:20 AM
Potclays are excellent for all materials including flint. Many packs start at 0.5 Kg
delivery by FedEx 25kg  £9; 50Kg £15.60; All plus VAT

http://www.potclays.co.uk/ListProducts_129.asp

Special Plasters do most of the same including Molochite and everything for casting and mould making.
Delivery 50kg £12.50 again all prices plus VAT.

http://www.specialplasters.co.uk/index.php

I have dealt with both firms and they are very helpfull and answer any question you could ask .....about their products  ::)

Regards Pete
Title: Re: Heavy items
Post by: Sandera on October 05, 2012, 02:32:21 PM
Many thanks for all the replies and links. I knew you'd come up trumps!