CUTTING TOOLS (DEFINATION OF OPERATIONS)

A tool which is used to cut or/and form sheet metal is know as a presstool. Usually this cutting and forming is done in combination with a machine, called press, (excenter press, mechanical press, hydraulic press). A press tool is made in order to manufacture hundreds and thousands of indentical components in comparetively short time. This means that a press tool makes it possible to produce sheet metal parts in on economical way, economical in terms as long as mass production is required and/or regular dimensions have to be maintenence.

The presstools can be basically divided into the two following categories :
a. Cutting Tools
b. Forming (non cutting) tools,

Cutting Tools (Punching Tools)

Blanking
The operation of punching about a complete contour is called blanking. The product is a blank. The blank is punched (cut) out as a plain stockstrip (coil).
A scrap coil is easily identified : in reguler intervals openings (scrap openings) of identical shape appear. The scrap - share per blank is high. In this respect blanking is not very economical. However, if the shape of the component makes it necessary we use this method. Blanks are produced in blank through tools (Component falls through die on bottom plate) or in inverted blanking tools (Components is ejected, from the die which is fixed on the top plate) .

Piercing
When opening(eg. holes) are punched (cut) into a blank or a semifinished product, the operation is know as piercing. The unwanted material (scrap) is called slug.

In the same books to the operation what we define (within these notes) as piercing, is referred to as "punching" (for round, oval or square openings) and slotting for cutting slots. We combine cutting of any shaped openings in the some ter piercing.

Notching
Notching is some how similar to piercing but the punch does't cuton all sides. It might act on 2 sides (free corners prior to bending) or three, but never on all. Nothing is used to fee sheet metal for drawing and forming (in progressive dies, see later) and to cut step by step the contour comlicated shaped blanks (also progressive dies). The cut out material is scrap.

Scropping
This is a scrapless operation. The width of the components is equal to the strip-width. The length of the part id determined by the feed. This method is used when the components shape is not comlicated. Moreover burrs have to be accepted on each opposite side once.

Parting
This operation is semi scrapless, scrap occurs only where the part is cut off (separated) from the strip. This method is frequeintly used when the component shapes are more complicated in one diricttion and straight in the other. The tours of the two shaped and might be different to each other.The burrs appear on the same side (toward the die opening).

Lanzing
When part of the material is cut (sheared) and the so feed portionis bent we know it as lanzing. Cutting is done at 3 edges. Bending takes place dring the same presstroke. Scrapless operation - combination shearing/bending. (Sometimes this operation is refered to as semi piercing).

Semi-Notching
This is a similar operation as lanzing. Cuttinng(shearing) is done at te most on 2 edges only since semi - notching is performed on least one outer board of the part.
Cutting and bending are done at the same press-stroke. Srapless operation combination shearing/bending. Sometimes this operation is included in "lanzing"

Shaving
Shaving is the only sheet metal cutting method which is not based on the shearing(fracture)principle, it is a chipping operation. Shaving is used when we want a high quality surface of a previously cut edge or dimensional accuracy or both. Blanks as well as pieroed holes an be shaved.
A very small amount of the fractured edge is removed. In extreme cases more than one shaping is recomended. This applies for very thick components and or extremely high accuracy. No cutting clearance is made.
In order to obtain good shaving results it is important that the previous cutting operation has produced awell finished cutting edge.

Trimming
Trimming is another finishing operation. This method is applied to remove excess material of forged or deep drawn parts. If the trimming cut is done in 90 degrees to the usual (vertical) direction we call it horizontal trimming.

Non cuttng tools defination of operation

Bending
Bending is defined as shaping sheetmetal around a stright axis which extend ompletely across the width or leght of the part. If during that bending the metal is stessed beyond the elastic limit but below the ultimate tnsile stereght it results in a permanent new countour.
The new countour is at an angle to the original (partlu remaining) one. Bende are made (in addition to obtail new countours) also to achive more rigidity.

Flanging
It is a similar operation as bendinbg. It is difficult to say where flanging ends and bending begins, The operation is known as flanging when the amount formed down is small compared to the remaining one. If the shape anyway shape of the flange (bend) is curved we call it anyway flanging.

Coining or stamping
Coining makes two sided impression or projextions by means of compressing the material in or arround the desired shape. On the opposite side of the impression no respective mark is visible but another design is impressed. If coining is one sided (opposite side flat) it is known as embossing. Typical application of coining making coins.

Semi piercing
This operation is similar to embossing. The difference is that opposite as the impression we fird projecttions. It is used for forming reinforcing ribs, welding projections to permit assembly by resistance welding.

Deep drawing
Deep drawing techique permits to produc semless hollow containers of regular and irregular shapes.
The metal is drawn by the punch and die. Blank holder pressure is applied to control the material flow. If the blakholder pressure is required it is know as form drawing.

Crimping
Crimping is a sort of bending. It is appli3ed to assemble electrical wire to sheet metal (brass, copper)

CURLING
Curling means rolling one-edge of a flat sheet metal blank, curled components are very rigid. Sometimes two curled parts are assembled to form a lid and a can. The assembly is not leak proof.

FORMING
Forming as such is difficult to define since it is general expression. It has become a bit the collective term for as unusual, indefinable forming operations as long as a pad is used.

COLLAR DRAWING
This is actually not cutting operation. It is scrapples and the material is torn and formed. The punch is bullet shaped. Although we call it “Collar-Drawing” it is not a typical drawing operation. We can easily identify application for collar drawn openings id to offer extended length for holes which are to be tapped. Sometimes this operation is known as “hole flanging” provided a hole is pierced before.

SUMARY OF CUTTING OPERATIONS
Operations to Produce Blanks
- Shearing
- Blanking
- Cropping (Cut – Off)
- Parting
- Shaving (secondary operation)

Operations To Cut Holes
- Piercing
- Hole Flanging (pre–cut collar drawing)
- Shaving (secondary operation)

Scapless Operations
- Shearing
- Cropping
- Lanzing
- Semi-notching
- Collar drawing



OPERATION SUITABLE FOR PROGRESIVE WORK
Cuting Operation
- Pierching
- Blanking
- Nothing
- Parting
- Cropping
- Lanzing
- Semi-Notching
- Shaving
- Trimming

Non Cutting Operations
- Bending
- Flanging
- Coining
- Embossing
- Semi- Piercing
- Deep Drawing (limited)
- Crimping
- Curling


TERMS FOR PRESS TOOL PARTS
Punch: The male part of a press tool, is fixed either with the top or bottom plate. It determines the dimensions of openings. Material : Preferably High Cromium High Carbon Steel, Hardened and tempered 60-62 HRC.

Die : is the female counter part of the punch and therefore fixed on the opposite appropriate plate. The die opening determines the dimensions of the outer shape of components. Material : Same as punch, hardened 60-62 HRC.

Bottom Plate (die shoe)
Supports usually the die (Except for inverted or compound tools) and locates guide pillars. Migh be graded cost Iron or Mild Steel (40 kg/mm2)

Top Plate (Punch Shoe)
Support normally the punches or punch holder plate (Except for inverted or compound tools), accommodates guide-bushes, shank. Material : Graded Cast Iron or Mild Steel (40/mm2).

Guide Pillar, Guide Bush
Are assembled as a matching pair to locate top plate and bottom plate accurately. Material : Carbon Steel Hardened.

Shedder
Use in compound or inverted dies to eject the blank, medium alloyed steel, hardened.

Punch Holder Plate
Holds smaller punches and is fixed and located with the top plate, Mild Steel.

Pressure Plate (Thrust Plate)
Is mounted at the back of the punch holder plate to take the punching pressure, medium alloyed steel, hardened.

Stripper
Strips coil (fixed or spring loaded) and pierced components (spring loaded) from the punch medium alloyed steel, hardened. Fixed stripper serves as punch guide in case of absence of guide pillars.

HOW TO GET NICE MUSCLE TONE AND BUILD AN ATTRACTIVE MUSCULAR BODY

Most people know that they need to lift weight build muscles. However many just want to have nice muscle tone and an attractive but not too muscular body as they do not want big muscles. So they just lift light weights with high repetitions. Well, it is not going to work. To have nice muscle tone, you will have to build some muscles right? So you will have to lift heavy to force your muscles to grow. Once you are satisfied with the size of your muscles, you will then need to cut your body fats for your muscles to show up well and that means nice muscle tone.

You need to have a solid commitment and knowledge to get nice muscle tone and build an attractive muscular body. Here are some muscle building tips. Before you commence weight training, remember to warm up and as well as doing some

Because of this, it is important that every time you train hard, you give your body time to recover as it has suffered strains and actually sustained many small scarring. Contrary to popular belief, your muscles grow when you rest, especially when you sleep and not in the gim. So sleep at least 8 hours a day. Also, do not train everyday or work the same muscle group more than once or twice a week. If your training was vigorous enough, do no more than an hour per session.

Try not to do cardio work on the same day as your weight lifting work. In fact, during the muscle building phase, you should do less cardio work as aerobic exercises burn muscles. You can increase your cardio work at cutting body fat phase, so as to lose body fat in order for your muscle tone to show up nicely.

•Technique And Form

This is the most neglected fundamental of bodybuilding. Everywhere, everyday, you will see people using wrong forms and techniques. This not only compromises your growth, it will also make you susceptible to injuries... sometimes even permanently putting you out of the gym.

Wrong form occurs usually when people try to lift weights that are too heavy, whether out of vanity or ignorance. As a guide, always lift with strict focus on the muscle you intend to build for that ecercise. Feel it contract and extend. Lift the weights deliberately and slowly. Never ever swing your weights up especially when doing bicep curls or the military press.

•To Build Muscles Fast You Must Perform Lower Body Exercises!

This is what most people don't realize. Your lower body makes up 60-70% of your musculature. If you don't train them, not only will you look spider-legged, your entire body will not grow as quickly and as large. Don't think that you can hide those skinny limbs in pants! Most people do not train their legs because squats, dead lifts and lunges can be very grueling exercises. But it is precisely because of such intensity that you will produce more growth hormones when you sleep and overall muscular development is stimulated. Your body shape will also be more balanced and therefore more attractive.

Do read up more to understand how your muscles work and then work on it so that in no time you will be a proud owner of a well tone attractive muscular body.