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moorepants / eme150a

Website for my UCD EME150A Mechanical Design course.
http://moorepants.github.io/eme150a
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Create a simple demonstration of transverse shear #22

Open moorepants opened 7 years ago

moorepants commented 7 years ago

my first attempt was to stack 1" wide sheets of paper to make a "beam" and then I draw vertical lines on the side of the beam. Finally, wrap it around a coffee cup to show the distortion in the beam.

viviantran27 commented 7 years ago

In one of our last meetings, we talked about creating a bending demo and a transverse shear demo, but they can maybe be combined into one demo. I haven't done the calculations, but I'm thinking about layering silicone and hot glue to create the layers in a plastic mold (which I'd probably just break to remove the demo piece). I know silicone probably won't adhere to the hot glue, so, I could also add layers of Loctite or some other silicone glue in between the layers of hot glue and silicone. Do you think this'll work for demonstration purposes?

bending demo mold

moorepants commented 7 years ago

I'm not sure I understand this picture. We should talk in person.

moorepants commented 7 years ago

If you go with this mold, I don't think you need the slots inside the fingers. Wouldn't it be better to make the fingers in the mold solid?

viviantran27 commented 7 years ago

Bending demo was 3D printed first, but it didn't bend enough to see the deformation before it snapped. Then I made a silicone mold and hot glue cast of the same shape and turned out okay. It shows the bottom spaces contracting and top spaces expanding, but it's dramatically more flexible than typical beams. Is this okay, or would you like to me to try a stiffer material and/or decrease the 1/8" spacing? img_2934 img_2933

Also, for the transverse shear demo, I found 1/8" thick Komatex plastic at Tap Plastic and am planning on layering silicone in between, but it seems like silicone may have issues adhering to plastic. The silicone layers are uneven, so I'll redo those for now, unless you know of a different material that's less chemically-resistant/ may work better. I tried hot glue and Komatex, but hot glue didn't adhere very well and was too stiff to bend before the layers separated. img_2935 img_2932

moorepants commented 7 years ago

These look cool. Can you bring them to me and show me? Thanks.

viviantran27 commented 7 years ago

Sure, I can stop by after 6 if you're still at your office.

Vivian

On Thursday, January 12, 2017, Jason K. Moore notifications@github.com wrote:

These look cool. Can you bring them to me and show me? Thanks.

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moorepants commented 7 years ago

Yes, that's good.