BlackDiamond SQUEEGEE RUBBER is a unique formulation to maximise both your 'speed on the glass' and the 'long-life' of the rubber to give you maximum efficiency.
Composite materials have a 'Hardness Factor' called the SHORE A FACTOR - it is the universal measurement for elasticity, and it defines a lot of the behavior of any one particular rubber on the glass.
Our Window Cleaning Industry has, for 80 years now, used two rubber formulations - SOFT and HARD - with SHORE 48 and SHORE 60 being the true definitions.
SOFT RUBBER (48 shore factor)
On the negative side, SOFT RUBBER will wear quickly on the glass, and on the frames - even on the edge of a plastic injected BOAB.
On the positive side, SOFT RUBBER will wear through its shiny outer layer rapidly, and it is forgiving through a range of motion angles, making it ideal for pole work.
Over the decades, generalisations have been made that SOFT RUBBER is ideal for use in colder ambient temperatures, as the rubber will behave more firmly in colder conditions.
The major reason Ettore SOFT actually behaves differently to Unger SOFT, is that they are a different profile - the ETTORE protrudes further from the channel edge compared to an UNGER. The reason we prefer the shorter profile is to ensure 'the window cleaner controls the squeegee, not the squeegee controls the cleaner". If the blade is 'tighter', you can develop and maintain a perfect working angle. If there is more flex in the blade as a result of it being longer, this becomes more difficult to achieve. We know the goal is to clean as much glass in the least amount of time possible, and that 'boils down' to an efficient technique.
HARD RUBBER (60 shore factor)
On the negative side, HARD RUBBER will take some time to 'wear-in', and it is not as forgiving through the range of motion - especially with pole work, tending to 'chatter' across the glass.
On the positive side, HARD RUBBER will last much longer, so if your technique maintains a very constant angle on the glass, you will get much more life out of a hard rubber. It is also much more resistant to 'burring' the corners on the frames.
Over the decades, generalisations have been made that SOFT RUBBER is ideal for use in colder ambient temperatures, as the rubber behaves more 'harder' in colder conditions, and HARD RUBBER is better in hot conditions as it behaves more 'softer'.
BlackDiamond SQUEEGEE RUBBER is also made with two formulations - one is SOFT (48 shore factor), emulating the behavior of the other SOFT RUBBERS in the market, and currently following the UNGER profile.
Now - you will notice that BlackDiamond Squeegee Rubber is two blades joined together when you receive them. This is unique to BlackDiamond to ensure you have THE SHARPEST EDGE - because the leading edge of each blade is fully protected from factory, till the day you use it. This is to ensure your most valuable asset is not exposed to the risk of premature damage and uneven wear.
MEDIUM RUBBER (52 shore factor)
While SOFT RUBBER behaves 'hard' in cold conditions, and HARD RUBBER behaves 'soft' in warm conditions - BlackDiamond saw the chance to make a more universal squeegee rubber - we call it 'MEDIUM', with SHORE 52.
BlackDiamond MEDIUM RUBBER has the benefits of SOFT, yet with a longer life. It does take a little longer to 'wear in', so don't judge it first time on the glass - give it some time ...
BlackDiamond MEDIUM RUBBER is a much more universal rubber for all climates, however, knowing the range of angles you go through when 'poling', it is not as forgiving as SOFT when doing pole work - there is still a case for SOFT if you only have one setting for your rubber in your channel.
PACKAGING MAY VARY, depending...