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Small syringes - need hydraulics?

Trying out the small 5ml syringes with a 40cm long tube I found that there was little force transferred in a pneumatic system. I could easily hold the plunger in syringe whilst moving the other through its full range of movement. With no load the syringe only moved 3.5ml when the drive end moved 5ml probably due to the friction inside the syringe countering the pressure change. After filling the system with water much more force was transferred and much more quickly. I didn't try to stop the syringe moving too much as I didn't want the tube to pop off and spray water all round the room. I found a 6cm length of masking tape cut in half lengthwise and wrapped around the syringe nozzle made a good seal.
Inventor 2019 Wow, another new program to figure out. I need another HDD in my laptop, this has left me with less than a gig of space!! When I started playing in Inventor it couldn't get it to draw a simple sketch of a rectangle with a semi-circle on the end. I was working on the XY plane and the curve kept going the wrong way. I tried it on the XZ plane and it worked. Now I can't replicate the original, frustrating actions that Inventor was insisting on doing. So I can now create a 2D cross-section sketch, set dimensions on it, extrude it into a 3D shape, draw new sketches on faces, extrude those new sketches or create cuts through the solid and drill holes by setting a point and then creating a hole. Next steps - find out how to move out of Inventor into a form the milling machine can understand and then look at what needs to be done in Inventor to create sufficient into for the mill to cut shapes out of sheets of MDF. UPDATE - I found that it all depends on which way
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Putting photos onto blog posts To put photos from my phone onto my blog I had to share them to to Google Photos rather than to my Google Drive. On Blogger, when you click the Insert Photo button you get options From your phone and this lists all photos that you've uploaded to Google Photos. Is there a better way to add photos to your blog? If you know of a different way let me know in the comments. Cheers Adding Video !!! It looks like two options for adding your own video to the blog. Either Upload - send it to your computer so you can upload it to Blogger or My YouTube Videos - upload it to your YouTube channel and then link to it.
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Pulleys and Levers A pulley works like a lever. You can use them to reduce the force needed to move an object but the payoff is that you need to pull more rope through the pulley or move the end of the lever further. Force x Distance = Word Done (which is the same as energy, which can't be created or destroyed) So if you arrange the rope to go around the pulleys such that there are 4 lengths of rope that get shorter when the load moves up (both of these diagrams are the same arrangement) we will need to shorten the rope by 4 times the distance the load moves up. So the force on the rope will be a quarter of the load. The quarter load balances the 4 times distance.
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Thinking is HARD (especially period 5 on a Monday) Today I asked my class to investigate how far the end of a lever moved and how it was related to where the pivot was. Their first suggestion as to how we could find this out was to go straight to Google!!!!! After an explanation about cardboard and skewers and several diagrams on the board the idea of being systematic about gathering data seemed alien to them. "How do I measure this," was a frequent question and the answer "That's a good question, how do YOU measure it?" was greeted with quizzical looks. In 40 minutes one group of two had about 5 results, a singleton had several results, a trio had none and a group of seven had 2 results. A couple of groups had opened up Google Sheets to record their results which could lead to good things. Here are my results
Degrees of Freedom Each different motion is a degreee of freedom. These can be linear or rotational. Linear is moving in a direction: Forward and backward is one degree of freedom, side to side is another. Rotational is turning at a point. Turning your head left and right is one degree of freedom, nodding your head up and down is another. The number of pieces of information needed to specify the position and state of the object we are talking about is the minimum number degrees of freedom in that system. A child on a swing has one degree of freedom. If you know the angle the swing has moved from the start position you know exactly where the child is. A position of a box of tissues on a desk has 2 degrees of freedom. If you know how far it is from the side of the desk and how far it is from the front of the desk you know where it is. Or you could know the angle it makes with the front of the desk, as measured from a particular corner and how far along that line it is - still 2 Do

First Lesson

Wow...I made a blog and this is my first post. I've never made a blog before so I'm interested to see how this can work for keeping track of work, learning and gathering evidence. In the first lesson we played with syringes. Found that air is squashy -  compressible  and water was not -  incompressible . We also found that you can make a popping noise. This is because the air molecules are far apart and so can be squashed together whereas the water molecules are already close together and so can't be squashed any further. Pneumatics is the use of air to power machines Can be cheap as air  is free Doesn't contaminate product so good for food processing applications Good for quick movements as air is low density Hydraulics is the use of liquid to power machines Precise movements as fluid is incompressible Can transfer greater force Oil can lubricate parts whilst moving them Some fluids are toxic Some fluids can operate at high temperatures (such as brak