So why the big delay? Well, the LTS350 utilised an electro plated machined copper heating/cooling element. As you are no doubt aware, copper is an excellent thermal conductor but oxidises very quickly. Take it up to 350C and the problem is exacerbated.
Since our new T95 controllers have extra heating capacity we wanted to ramp up the performance of the LTS stage to 420C, however, the electro plating can only do so much to protect the copper from the oxidising environment of a heating stage. Early silver plated prototypes seemed to work well, but manufacturing these elements at a consistently high standard proved to be far more difficult than we anticipated.
How did we solve the problem? We now make pure silver LTS heating elements. This is of course a more expensive material and from a technical point of view virtually impossible to do. Pure silver is a very soft metal and a complete nightmare to work with. Designing and building a perfectly flat pure silver heating element was extremely difficult, but after many prototypes, we have nailed it.
The new LTS420 stage will go up to 420C at 50C/min. It is a fantastic new instrument and hopefully well worth the wait.