Day Eight.... Rated Operation

..... what? I hear you say, "Rated Operation"? Don't worry, more of that later. First, the latest news from around these parts.

Well the sun came out a little bit so Ginny & Nigel decided that as it was such a nice afternoon that snoozing in the conservatory was the best plan.

Now, since Mummy has been away, I have had a bit more time to do some thinking. Do you know that between naps, those cats go out 15 times a day, each! Sometimes they only go out for less than one minute before they want to come in again! This means that Super Nan is effectively running a marathon (26miles 385yards) EVERY WEEK just letting those cats in and out. I would like to point out that I only go out twice a day and this is only when the other humans are going out anyway. So here's the thing, what has been keeping me awake at night is the thought that the door mechanism is being operated 90 times a day, as of course the cats cannot get organised to come in and go out together. Now when a company design a product, they design it to have a certain life span, or operate a certain number of times. A uPVC door mechanism is quite complex as it not only operates the handle and yale type lock, but also throws the four additional locking points on the side, top and bottom of the door. Now I have checked with Hazlemere Windows, the locking mechanism for our patio door was designed for 50,000 operations, with an average operation over the year of 65 operations per week, it should last around 15 years. However, with those pesky cats going in and out so often it means that the patio door is being unreasonably accelerated towards the end of its design life. So that means that, in one year here, the door is getting ten years use! ...... so, if I just work out.... the length of time that we have had them, subtract the installation date, from today's date........ means that they will be life expired................ oh, um, er.......... tomorrow. Oh. I think that is what Windows (excuse the pun) would call "An unexpected result".

For completeness, I have included a drawing of a typical lock mechanism, although sadly at the time of going to press, the stress calculations were not available.