Presentation on theme: "1 Working with the Workshop Andy Edgar. If you can buy it from a catalogue, buy it, don’t build it. 2 US $400."— Presentation transcript:
1 Working with the Workshop Andy Edgar
If you can buy it from a catalogue, buy it, don’t build it. 2 US $400
Strategies Don’t be lazy – design it yourself –that way you get what you want, or at least asked for. 3 But get the WS to check a sketch first for manufacturability. Get as much right as possible first time, but allow for mods.
Find 10 things wrong with this job request 1.No date 2.No charge code 3.Who is Dave? Contact details (room, phone #) 4.No idea of urgency 5.Material not specified 6.Thickness not specified 7.Quantity not specified 8.Depth of 5 x 5mm recess not specified 9.They can’t easily make a 4.37mm hole 10.They can’t make a square recess with a milling machine 5
The lathe - turning 6
What can be done on a lathe 7 Routine Tolerance 0.1mm
Making Holes/Threads 8 Drills – only fixed sizes –typ. 0.5 mm increments Tolerance - ~ 0.1mm
The Vertical Mill 9 For making flat surfaces Tolerance ~ 0.1mm CNC – Numerically controlled
Sheet metal working 10
For a 6mm screw, the 6 mm means 1.The distance between consecutive turns 2.The diameter of the head 3.The maximum diameter of the threaded part 4.The minimum diameter of the threaded part 11
Screws and Bolts Which of the following heads are described as, –Phillips –Knurled –Countersunk –Allen/Cap –Hex –Cheese –Posidrive 12
Which Material? Which of these W/S metals are not “pure ( >99%) metals? –Brass, copper, aluminium Which of the W/S materials would you use for, 1.A cryostat for liquid nitrogen/helium? 2.A sample holder for cryogenics 3.A good electrical insulator for T<200˚C 4.An electrode holder for high temperatures? Which metal would you not use for vacuum? Which metal is the most expensive? 20
Joining Materials 21
Soldering and Brazing Soldering ( ˚C) –Brass, copper Sn-Pb (banned) Tin-Antimony –Have to remove surface oxide first with flux Brazing ( ˚C) –Brass, copper, steel, SS Brass brazing rod, or Ag-Cu-Sn “silver solder” Hydrogen acts to clean surfaces 22
Welding Mainly steel, any other metal incl. Al Filler of same metal used to reinforce joint Localised electric arc melting of metal and filler. TIG – tungsten/inert gas (argon) 23
Glues Aim for thin joints, clean surfaces first Standard 2-part resin (araldite). Soften in acetone, flame. Silicone RTV Thermosetting polymers and resins ( hot glue) 24 Superglue (cyanoacrylate) Soluble ceramics for furnaces Low vapour pressure resin (Varian) Silver-filled epoxy, silver conductive paint
Two Examples of Clever Design 25
“Kinematic” Bearings 26
Translation Platform 27
Drawings Hand drawings are fine Ruler is good for straight lines! Use grid/graph paper To scale is best Sketch, front, top, side views for clarity (conventions) Specify ID, OD, threads, material If frequent user, consider CAD ( eg SolidWorks) 28
Acknowledgements Many diagrams and info from, “Building Scientific Apparatus” JH Moore, CC Davis, MA Coplan, SC Greer (new copy ( 4 th edition) ordered for library) 29
30 Table of Contents 1. Mechanical design and fabrication 2. Working with glass 3. Vacuum technology 4. Optical systems 5. Charged-particle optics 6. Electronics 7. Detectors 8. Measurement and control of temperature Index.
3d Printing - Justin 31
3D Printing For personalised, custom-made lab equipment. Requires a 3D design- solidworks 3D printer- School of Architecture and Design.
Solidworks The final design is sent as a.stl file to the printer. The design is printed by slicing the design into 2D digital cross sections and depositing the materials layer-by-layer. Materials used include thermoplastics eg. acrylonitrile butadiene styrene, polycarbonate, polylactic acid. A 3D Computer Aided Design (CAD) software used to create a model. The design starts with a 2D sketch and is extruded to give a 3D object.