Mechanics Tensile Lab Test

This week I had to hand in a Laboratory Report. The lab was on material tensile strength, looking at the stress/strain graphs exhibited by different grades (Carbon percentage) of mild steel. The machine we used was a Hounsfield Tensometer.

A part of the report was to describe and explain the equipment used in the experiment. To accompany the text I wanted some images, but I was unable to find images that represented the equipment with any sort of cohesion. To solve this I decided to take the best images I could find, whether sketches, technical diagrams or a couple of photos taken by me, and use Illustrator to create some simple vector outlines.

These show the different equipment used from the top, the Hounsfield Tensometer, the samples used, a Tinsley Strain Measurement Bridge, Ultimate Area Reduction Gauge and Ultimate Elongation Gauge.
Below are a couple of pictures I took of the experiment at the time, they weren't too good but I did use the one on the right for the Bridge.

Finally a couple of graphs from the results of the experiments. The one on the left shows the stress/strain curves of 0.1%, 0.2%, 0.4% and 0.8% Carbon Steel, while the one on the right is the Elongation, Yield Strength and Ultimate Tensile Strength against the increasing Carbon %.

Metal Workshop- Trammel (5) Complete

My first workshop is now finished, and about time too. Above is the completed trammel which was finished on Wednesday, marked on Thursday and I picked up on Friday. Hopefully I got a good score as I finished on time and managed to get a reasonably good finish and degree of accuracy into the tool. It has been fun making it and as a first time making something of this nature, it feels good to know that I have made something that I would not be surprised to find in a shop, due to the accuracy of the machines I was using. And because you probably know all there is to (or would want to) know about this, I'll just leave you with some pictures of the final object.

The Trammel in it's various components.

The main body of the trammel

 The trammel pen and lead holder and the extension

And some close ups of the trammel

And finally, my stamp of ownership, on both of the two point holders.

So that's the end of that part of my course, hopefully passing the workshop so I can be deemed safe to use it next year, and now another break for two weeks for graphics before the wood working workshop for two weeks before Christmas. (p.s I've only just found out it's a 'Trammel')

Metal Workshop- Tremmel (4)

A quick update of my process at the moment with the tremmel, with half a day to go till it is marked, and progress is good.

The main body of the tremmel

With the extension above it.

Some closeups of the completed components in place.

My initials stamped onto the side of the pin holders.

And finally some extras, on the left is the first part of a components to hold a lead, the right is a pen/pencil extension to the tremmel however because I made a slight mistake, it is now also optimized for holding a scalpel as well. So anyway, the final making day is tomorrow, and all looks well.

Metal Workshop- Tremmel (2)

 So I've had two more days of work in the metal workshop since I last showed my work, and it has advanced considerably.

I have now advanced from just the metal working lathe, I have now used both a milling machine (for straight machined cuts) and a Collet (a highly accurate lathe). So above are all my components so far, all of them are at the furthest stage I can take them at the moment, so in my mind I have done pretty well. The individual components are below.

 Bolt x6                                        Tremmel Head x2

Extension Cap x1                                 Wheel holder? x1

 Adjustment Wheel x1                                  Collet Cap x2

M5 threaded rod x1                              Steel Point x2

Measureing Rod x1                                 Extension Rod x1

While all of the components will fit together to create a single tool, some of them are already made to fit and below are the different attachments so far.

 Extention Rod and Cap and the Tremmel head, collet cap and Steel point

And the adjustment wheel and wheel holder.

So thats where I am at the moment, no more work on this till next week where we will be doing much more work on the milling machines.

GCSE DT Key Fob

So some design stuff today, there's been a lot of art recently (and still more to come). This is a return to a design I did while doing GCSE D.T.

The brief was to make a simple key fob (ring) out of metal so that it could then be dip coated. As you can see below I didn't quite get that with my first design which was the biohazard warning symbol. The 3D render is done in Google Sketchup.

 

So this is the revised design where I stuck with the same sort of idea as before but just simplified it to the radiation warning symbol. Again Google Sketchup.

So this is how the key fob ended up at the end of the project at school. As you can see I never got round to the dip coating stage, but no one else did either as we ran out of time (mainly due to the thickness of the mild steel it's made out of).

 

 So I returned to this today and with some sandpaper and wirewool I got rid of the small bits of rust on it, cleaned up the edges and surfaces and attached a small chain thing I had lying around.

 So there we are. Thats a sort of closure for this miniproject, thanks bye.