First and foremost, both functional and cosmetic considerations are involved. This may require careful mixing and colour matching of a silicone moulding compound, with no air entrapment, to ensure appearance and consistency of structure. Jim Dimond, consultant clinical maxillofacial prosthetist at University Hospital Coventry, explained how the Thinky ARE-250 from Intertronics helped move from a lengthy, manual process, requiring a skilled technician, to a short, reliable and automatic mixing process.
"Originally, mixing at the hospital was carried out by hand using a palette knife in two stages – mixing and then flattening on a flat glass plate to squeeze out the air. This was arduous – especially for larger quantities required for hands, breasts, facial and other components – issues equally applicable to other silicone applications, such as theatrical masks, plaster casting, special effects, model engineering, animatronics, life casting and pattern-making. The manual procedure was laborious and very time-consuming, as it generally required use of fillers for changing consistency and small quantities of intense colour pigment being mixed with clear silicones to suit the individual patient."
Seeking a more efficient method of mixing the compound and other components, Dimond contacted product specialist David Peat at Intertronics for a demonstration of the Thinky ARE-250 non-contact planetary mixer. The Thinky process, by means of both rotation and revolution of the material, mixes and degasses at the same time. The constituents are simply measured into a container that goes straight into the machine, saving time while reducing material waste and clean-ups.
The Thinky solution was seen as excellent for small quantities and also worked particularly well with their system of pre-preparing large batches of colour coded silicone – which was especially arduous and time-consuming. The Thinky ARE-250 was found to easily process even highly viscous material and, once programmed, ensured a thoroughly mixed, bubble-free compound to the required consistency for every batch without further intervention.
As Dimond commented: “I have been doing this work for about 12 years and for the past 12 months have used the Thinky a great deal. It has allowed us to quickly produce homogenous silicone in large quantities that is free of air, transforming a time-consuming, physical task into an automated effortless one.”
