week 3 proposed:
This video is OK, watch for his mistake which he in turn fixes. It’s just a good example how hard it can be to read a vernier calliper and how much attention you need to put into learning this low tolerance measuring tool.
This video about reading a metric micrometer is good. The narrator relates the metric tool with an imperial tool. I will not teach the imperial tool, but it’s still widely used in industry. For example “its out by about 18 thou” … what does this mean? 18 thousandths of 1 inch. That is the equivalent of less than 500 micrometers or 0.5mm. 39 thou is equal to 0.9906mm. Not important? Go for a job interview and do not know this.. and you maybe will know how important it is after you are not successful at the interview. There is a strong link between reading manual measuring tools and reading electronic meters with fine scales.
You can go and search Youtube and find many links to great videos about video. You can also search sharing sites to find many powerpoint about vernier callipers and micrometers. These pictures below are from some of my teaching material in powerpoint for classroom use.
To the afternoon practical session:
Most people finished at least one good hard drive spacer. The metal folding and bend radius allowance as we had learned in theory is not so easy to get right. You must think about putting the extra metal width from the bend, into the gusset area of the spacer, as I am measuring Outside dimension when marking. The tolerance is +/- 0.5mm…. i.e., 21.5mm to 22.5mm. Get that wrong, you panel beat the spacer and do the folding again.