aerobysam

sharp flat tip that removes materials with the aid of hammer. Cold Chisel: made of tempered steel used to cut cold metals. The various types of Cold Chisel are: 1. Flat Chisel (cut bars) 2. Cross Cut Chisel (slots) 3. Round nose Chisel (Semi- circular groses) 4. Diamond point chisel ( cleaning out corners)

Punches are a marking rod that marks metals with the aid of a hammer. Different types of punches: a) Centre Punch Mark the centre point to be drilled. Tip angle-60-90 b) Prick Punch (dot punch) Tip angle-40 c) Drift Punch (lineup punch) To align rivet or bolt holes. d) Number Punch e) automatic Punch Other types of punches are: 1. Pin punch To remove pin. 2. Transfer punch To duplicate hole patterns. 3. Roll punch/ Spring To handle spherical faced pin.

Screw driver is a fastening tool. It consist of following parts: 1. Handle 2. shaft 3. tip Classification according to tips A) Slotted type B) Cross/ Double Slot/ Cruciform type Different types of Cruciform type screwdrivers are: 1. phillips This type of head prevents from over tightening. This is done by allowing cam out.    2. frearson Reed and Prince designed this kind of head. This gives high torque and does not cam out. 3. French recess This has a protrusion. 4. JIS Japanese origin head which is similar to fearson but has a bigger size. 5. Mortorq This is light weight and high stress head which are generally more used in aero field. 6. Pozidriv This is known as improved version of Philips. This decreases likelyhood of cam out thus providing more torque than Philips. It consist of a tick at 45  degrees. 7. Supadriv This kind of head allows short offset between screw and screw driver. Resulting in increased efficiency and less c

Screw is an inclined plane introduced to a nail. A screw can have partial or full threads. Parts of a Screw: 1. Head Head is the top most part of the screw where the force is applied with the help of screw driver or wrench. 2. Bearing surface It is the surface below the head which produces an axial force to the substrate. 3. Thread 4. Pitch Gap between 2 threads is called thread. 5. Shank The conical area below the head is called Shank. 6. Substrate The surface which is to be screwed is called sustrate. Screws and Bolts: 1. Screws grip on the substrate, while the bold requires a nut to produce an axial grip. 2. The screw has only one bearing surface while bolt and nut combination gives 2 bearing surfaces. 3. Nut and bolt combination consist of both male and female threads, while screw generally has only male threads. Different Types of Screw heads: a) pan b) round (decorations) c) truss (mushroom, prevent tampering) e) flat (counte

Hammer Hammer is a force amplifier. Parts of hammer: 1. handle axis 2. Eye 3. Peen 4. Neck 5. Head 6. Strike surface Physics of Hammer: ME=KE=ME. Let us assume that a hammer strikes an object with force F, with distance between the hammer and an object before striking be D. Then the recoile distance be d and force of recoil be f- reaction force. Then, Energy= Force * Distance travelled* gravity here conservation of energy is in action. So, F*D*g=f*d*g Therefore f=D/d*F Here the force is being multiplied by a factor of D/d. The recoil percentage is the force multiplication factor. For eg: A titanium head gives a recoil value of 3%. A steel head gives a recoil value of 30%. Effect of Head mass If we consider 2 hammers, lets say titanium and steel, of different masses, m1 and m2. and m1<m2 KE= 1/2 m v^2 now KE is directly proportional to m and square of velocity. KE1=1/2 m1 v1^2   titanium KE2=1/2 m2 v2^2   steel For m1<m2 KE1=KE2,

There is not a specific guideline to which we could follow for the NAC exam. Here we need to gain as much information as we can. So lets start with the different Hand tools: 1. Hammer 2. Screw 3. Screw Driver 4. Punches 5. Chisel 6. File 7. Hack saw 8. Riveting 9. Drill 10. Vise 11. Soldering 12. Nails 13. Wrench 14. Bearing Different processes in workshop technology 1. Welding 2. Heat treatment method 

1. Fundamentals computer: history, comp system and organization 2. mech Workshop tech, material properties, sheet metal work, strength of material, stress and strain, torsion, pure bending thermo, heat transfer, heat engine instrumentation and measurement machine construction 3. management org and management,internal org of company, industrial eng and management 4. aero  aircraft wing, airfoil, flight control surface, basic theory of flight, propulsion, Gas turbine, Atmoshphere

NAC- Nepal Airlines Corporation is a national flag carrier of Nepal. It has an opening in 7th level for the post of aero/mech engineer. There are 4 sections in the syllabus: 1. Fundamentals 2. Mechanical 3. Management 4. Aero So these are the topics we need to research on. Study plan: The 1st thing to consider while studying for NAC is that the questions are all objective. So there will be 4 options and u need to tick the right one. As with my belief all the questions will be not so difficult but confusing. So to cope with this, i believe wikipedia is the major source of knowledge. I will be using internet based resources to study the syllabus. QN paper. There will be 50 qns with each carrying 2 marks. There will be no negetive marking. The total time given is 1.5 hrs. Exam time: The exam routine is not out yet, however it is somewhere around march, on the basis of recent exams. So 3mnths tops.

This is the day i make a difficult choice. I just finished a nights out with my friends in sundhara, of which my parents are oblivious, i decided to keep it a secret. I told them it was a nights out in a friends home. Actually we booked a room in sundhara and it was kind of wild. Humm i am off topic, the thing here is not about my new year eve but thing that is much more critical. i have come to this stage of my life that it seems like all my previous plans have failed. wait it is not failure in an absolute sense but a failure in a relative sense. This is because, initial me had planned my whole life, like i would do my masters in aeronautical engineering in Germany. Without knowing any scope of work there or if i return back in nepal. So this was old me. I had set my goals in such way. But now as i grow up and discover things. I found that being fixated to Germany was not a good choice. However this is not a sense of depression. I had good times in Deutsch classes. I made lot of good