Side Cutters
The side cutter is installed in the first position of the tool.this eliminates extra stops and simplfies both construction and peration of the tol.Usualy side cutter is located along the front edge of the stck trip.Two side cutters on each side is used when the number of stages are more or if the pitch is less.
Side cutter is an accurate method of stopping arrangement.It is mainly used for thinner strips where it is difficult to accommodate other types of stoppers.Side cutter is a trimming punch which trims the side of the stock material.A shoulder is formed on the strip.The shoulder is stopped against a hardened insert provided in the spacer.The width of the side cutter is equal to the pitch.
The allowance for side cutting depends on the type and thickness of the stock material.The size of the side cutter will be more than the pitch by 0.05 to 0.01mm when pilots are used in the tool.The pilots will register the strip at the correct location.But in tools without pilots the side cutter is made equal to the pitch.
unbalanced forces act on side cutters during the cutting operation.Therefore the side cutters are provided with heels.
Thorns(small projections) occur on the side of the strips due to side cutter wear ut.The undercuts provided on side cutter eliminates the difficulties of feeding due to formation of thorns.The slugs may go up with the punch.Slug pushers are used to avod this.
Advantages of using side cutters
1. It is a safer method than stop pins.
2. Avoids deformation of thinner strips by stop pins.
3. Preferred for small punchings where it could be difficult to employ other types of stops.
4. It is economical and avoids complications in tools where number of stages are more.
5. Pilots can be avoided for punching components with moderate accuracy.