Topic: Glasshouse Pots

[chopin-liszt]

And we also know that Caithness has been having dreadful problems with their pots recently, Christine - they told me so when I was there just before we saw you in Crieff.
They got through more than they should have, (was it 5 rather than 3 last year?) they've been patching things up and doing their level best to carry on, but it's a really, really serious problem - and contributing an awful lot extra to the already appalling expense of glassmaking.

[David E]

It seems to intimate that they make their own pots? Otherwise, I wonder why they are having so much trouble. It must be such a palaver and a kerfuffle changing the pots - there are enough videos and images to show what was involved. Not for the fainthearted! Pot-making was something each of the larger glass factories used to make themselves and a very skilled job it was too, but nowadays I imagine they are bought in.

[chopin-liszt]

I don't think so, David. The facilities are not that big in Crieff!
I was trying to glean as much info as possible in the 30 seconds before the shop shut, from a very knowledgable and helpful member of staff. I think I'll have to go back and get it again, when I'm not so much under pressure to remember everything that my brain did its collander thing...
What I do remember is that it is causing truly serious financial stress on Caithness and their ability to stay viable. The pots they've had simply haven't lasted nearly as long as they should have.

[ian.macky]

And don't I know it! Wished I had a hardcopy myself, but this is definitely the next best thing. Many thanks.

David, I have the 1968 Ceramic Book Company reprint, which was relatively affordable (US$50).  Wish I had an original, but nyet.  If looking for a copy (or any book), I recommend bookfinder.com, the best meta book-search engine I know of.

--ian

[David E]

Yes, I do use bookfinder occasionally, and abebooks is also a very good source. One day all these rare books will be on the net but, until then, we'll have to sit around with our legs crossed.

[Frank]

I have the original, wonder what that fetches now!

[sph@ngw]

can I just correctone small factual error in Adam's otherwise excellent post about pots, as someone inbolved in pot buying and use.
You do not "allow the furnace to cool, remove the old pot and heat it up again"!
A furnace has to be cooled slowly so as not to damage the refractories ( bricks, etc), so it would take three weeks to cool down and three weeks to heat up!
So you do a 24 hour pot set, by removing the bricked up front of the furnace taking out the old hot pot ( on a gun carriage or shielded fork lift truck) and replace a pre heated new pot and the bricking up again.
About 3 to 5 hours for a team of 5 guys who loose about 1/2 a stone (7lbs in weight0 through sweat and exercise.
At Nazeing Glass we got up to 18 furnaces ( single for of 750kgs a day). We now have four and two 100kg studio pots, but not all are in use!

[Fuhrman Glass]

I think several of the factories are getting their pots from a French manufaturer. I know my friend Tim Mosser at Mosser Glass here in the US told me last year that was the only place he could get them. and they are extremely expensive. there are several manufacturers here in the US but do make the larger sizes as they are very difficult to produce.
I also know that the Chinese are making their own but have a hard time getting the quality materials they need to make them with.

[sph@ngw]

For those of you who visit Northern France, there is an excellent museum "Glass vallee Museum at Blangy sur bres;e, the heart of the French bottle glass industry ( over 80% of the world's perfume bottles are made there by about four companies( or their overseas subsidiaries). La Glass Vallée www.la-glass-vallee.com/They show pot making in detail and several jockey pots for small colour runs.
You can also do a "concave" that means blowing cold air on the crack in the pot ( if accessible ) to cool the glass, like stopping a wound with congealed blood! This can sometimes last a few weeks....
Not pot makers do not gurantee their pots, so if it cracks on coming out of teh pot arch, they assume it must be your fault for poor preheating!
Some pots last 10 melts others over 100 melts. At over !1,00 each it makes a big difference to your costs!

[sph@ngw]

"I think several of the factories are getting their pots from a French manufaturer"
This is probably Rieux Refractaires in the Oise region, who claim to supply Lalique, Daum, St Louis etc, in France.They are expensive but good I believe.
I cannot find their website!