Brick Colorstream
Grangemouth test bricks
Top row is D bricks (all ABS except for one black CA). Bottom row is F.
Copied from WoutR's post:
In the 1960's, LEGO was not large enough to produce and control worldwide supply of LEGO brick from their own factory. Because of that, and because of import restrictions in several countries, LEGO was produced in a few different countries.
In the UK the licence was held by the Courtauld's Corp from 1960 to 1992. They produced LEGO in their Wrexam factory and distributed it to Britain, Ireland and Australia.
Around 1960, LEGO was searching for a replacement for the Cellulose Acetate (CA). It was replaced by Acrylonitrile butadiene styrene (ABS) around 1963. (Replacement was later in the USA, where licence holder Samsonite continued to use it.)
In my personal opinion, it is not surprising that LEGO asked their new licence holder to help them to come up with a replacement for the CA. They were used to working with plastic in their factory, so it makes sense to work together and use their expertise when they start a new production licence agreement that might soon be subjected to such a huge change. At the same time companies like Bayer and BASF also worked on similar projects.
I think the early "Wrexham bricks" in odd plastics come from that period.I am not sure how many molds were used for this. For the Wrexham factory, we know about the F1-F4 bricks and there is also a series with N-numbers.
After the choice for ABS was made, the molds previously used for testing new plastics were used for quality control.
We did not know anything about where Courtaulds/Wrexham got their raw materials or how they organised quality control, but recently (July/August 2014) we found out that the material was supplied by Borg Warner Chemicals in Grangemouth. We also learn that they had their own mold (F1-F4) for quality testing in their "color lab" before the raw ABS was send to LEGO (presumably the Wrexham factory).
In 1977/78 some employees at Borg-Warner wanted to experiment with some of the excess plastic from the regular LEGO production and used the mold to produce bricks with a "granite effect". The bricks they produced were given to children. They did not see this as a problem, because the marbled "granite" bricks could be clearly distinguished from real LEGO products. This might have been done with permission within the factory, or they might have been produced during night shifts, but I think LEGO was not pleased about it. As the story was told on BrickLink, the bricks were eventually spotted by a LEGO representative and the mold was taken away.
Grangemouth test bricks
Top row is D bricks (all ABS except for one black CA). Bottom row is F.
Copied from WoutR's post:
In the 1960's, LEGO was not large enough to produce and control worldwide supply of LEGO brick from their own factory. Because of that, and because of import restrictions in several countries, LEGO was produced in a few different countries.
In the UK the licence was held by the Courtauld's Corp from 1960 to 1992. They produced LEGO in their Wrexam factory and distributed it to Britain, Ireland and Australia.
Around 1960, LEGO was searching for a replacement for the Cellulose Acetate (CA). It was replaced by Acrylonitrile butadiene styrene (ABS) around 1963. (Replacement was later in the USA, where licence holder Samsonite continued to use it.)
In my personal opinion, it is not surprising that LEGO asked their new licence holder to help them to come up with a replacement for the CA. They were used to working with plastic in their factory, so it makes sense to work together and use their expertise when they start a new production licence agreement that might soon be subjected to such a huge change. At the same time companies like Bayer and BASF also worked on similar projects.
I think the early "Wrexham bricks" in odd plastics come from that period.I am not sure how many molds were used for this. For the Wrexham factory, we know about the F1-F4 bricks and there is also a series with N-numbers.
After the choice for ABS was made, the molds previously used for testing new plastics were used for quality control.
We did not know anything about where Courtaulds/Wrexham got their raw materials or how they organised quality control, but recently (July/August 2014) we found out that the material was supplied by Borg Warner Chemicals in Grangemouth. We also learn that they had their own mold (F1-F4) for quality testing in their "color lab" before the raw ABS was send to LEGO (presumably the Wrexham factory).
In 1977/78 some employees at Borg-Warner wanted to experiment with some of the excess plastic from the regular LEGO production and used the mold to produce bricks with a "granite effect". The bricks they produced were given to children. They did not see this as a problem, because the marbled "granite" bricks could be clearly distinguished from real LEGO products. This might have been done with permission within the factory, or they might have been produced during night shifts, but I think LEGO was not pleased about it. As the story was told on BrickLink, the bricks were eventually spotted by a LEGO representative and the mold was taken away.