Hollow needle is used to remove air under press. or under vacuum from the vicinity of fresh pieces of uncured rubber when applying new treads or local grafts to repair worn or damaged tyres. The needle may be used at =1 place either to pierce the structure and remove air from the internal interface between old and new rubber, or to remove air from beneath an elastic bandage or sleeve used to enclose the portion of tyre under repair. The perforation made by the needle is promptly sealed with a suitable rubber mastic as the needle is withdrawn. Method may be adapted for fitting either hoop or butt joint retreads or local tread pieces. Use of a needle at selected positions evacuates air more completely than use of covers evacuated by one external hose, where the cover may form a seal close to the outlet.
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