A finishing boring machine for a high-precision wheel hub hole, includes: a boring machine body, a hydraulic automatic centering fixture, a computer numerical control (CNC) vertical sliding table, a spindle box, a CNC facing head, a cutter assembly, and a hydraulic system. The boring machine body is a main structure of the finishing boring machine for the wheel hub hole. The hydraulic automatic centering fixture is configured to place a to-be-processed workpiece, and is arranged on the boring machine body. The CNC vertical sliding table is configured to control operation of the CNC facing head, and is arranged on the boring machine body. The spindle box is configured to control an operation speed of the CNC facing head, and is arranged on the CNC vertical sliding table. The CNC facing head is configured to control the cutter assembly to process the to-be-processed workpiece, and is arranged on the spindle box.

Disclosed is a drilling method for PCBs with high hole position precision, comprising: step 1 of fixing a PCB on a workbench; step 2 of pre-drilling a to-be-drilled portion of the PCB by using a short-blade drilling tool; and step 3 of deeply drilling the to-be-drilled portion which has been machined in step 2 by using along-blade drilling tool. The PCB is fixed in step 1 to prevent the PCB from moving during drilling which otherwise would affect the drilling precision; the to-be-drilled portion of the PCB is pre-drilled by using a short-blade drilling tool in step 2, and the short-blade drilling tool has a higher rigidity than along-blade drilling tool and thus will not easily slide at the moment of contacting the surface of the PCB; and the to-be-drilled portion which has been machined in step 2 is deep drilled by using the long-blade drilling tool in step 3, and the long-blade drilling tool has reduced sliding upon entry, thus guaranteeing the entry alignment of the long-blade drilling tool in the case of deep drilling, so that the drilled hole meets the requirement of high hole position precision for PCBs.

Entry sheet for drilling including a metallic foil and a layer of a resin composition, the layer formed on the metallic foil without interposing an adhesion layer, in which the layer of the resin composition has a peak attributable to a carbon atom-oxygen atom double bond appearing at 1700 to 1750 cm.sup.1 and a peak attributable to a carbon atom-oxygen atom single bond appearing at 1080 to 1300 cm.sup.1 in infrared spectroscopy, and when the absorbance at the peak attributable to the carbon atom-oxygen atom double bond appearing at 1700 to 1750 cm.sup.1 is represented by Abs(CO)L, and the absorbance at the peak of the carbon atom-oxygen atom single bond appearing at 1080 to 1300 cm.sup.1 is represented by Abs(CO)L, the layer of the resin composition has an absorbance ratio (C) of 0.12 to 1.80, the absorbance ratio (C) represented by the following expression (1).

Absorbance ratio(C)=Abs(CO)L/Abs(CO)L Expression (1)

Entry sheet for drilling including a metallic foil and a layer of a resin composition, the layer formed on the metallic foil without interposing an adhesion layer, in which the layer of the resin composition has a peak attributable to a carbon atom-oxygen atom double bond appearing at 1700 to 1750 cm.sup.1 and a peak attributable to a carbon atom-oxygen atom single bond appearing at 1080 to 1300 cm.sup.1 in infrared spectroscopy, and when the absorbance at the peak attributable to the carbon atom-oxygen atom double bond appearing at 1700 to 1750 cm.sup.1 is represented by Abs(CO)L, and the absorbance at the peak of the carbon atom-oxygen atom single bond appearing at 1080 to 1300 cm.sup.1 is represented by Abs(CO)L, the layer of the resin composition has an absorbance ratio (C) of 0.12 to 1.80, the absorbance ratio (C) represented by the following expression (1).

Absorbance ratio(C)=Abs(CO)L/Abs(CO)L Expression (1)

A tool including a pair of rails is attachable to the inside surface of the skin panel. A housing is pivotally and slidably connected between the pair of rails. The housing is pivotable about a first axis and is slidable along grooves in the pair of rails. The housing has a first end and a second end opposite each other. The tool includes a rod having a third end and a fourth end, the third end attached to and extending from the first end of the housing. The tool also includes a pressure foot attached to the fourth end of the housing. The pressure foot includes a curved ankle integrally formed with a flat flange, the curved ankle curving into the flat flange. The pressure foot is configured to apply pressure along a portion of the inside surface of the skin panel when the housing is in a vertical position.

An entry sheet for drilling comprising: a metallic foil; and a layer of a resin composition, the layer formed on the metallic foil without interposing an adhesion layer, wherein the surface of the layer of the resin composition, the surface being in contact with the metallic foil, has a dispersion term SD of surface free energy in a range from 27.0 to 37.0 mJ/m.sup.2 and a polar term SP of the surface free energy in a range from 0 to 5.0 mJ/m.sup.2.

An entry sheet for drilling comprising: a metallic foil; and a layer of a resin composition, the layer formed on the metallic foil without interposing an adhesion layer, wherein the surface of the layer of the resin composition, the surface being in contact with the metallic foil, has a dispersion term SD of surface free energy in a range from 27.0 to 37.0 mJ/m.sup.2 and a polar term SP of the surface free energy in a range from 0 to 5.0 mJ/m.sup.2.

The invention relates to a method for fine-machining a bore of a plurality of workpieces and a machine tool unit. According to said method, the workpieces are subjected to fine-hole drilling and precision finishing, preferably roller-burnishing or smoothing, a post-processing measurement is carried out and, depending on said measurement, the fine-hole drilling tool is adjusted.

The invention relates to a method for fine-machining a bore of a plurality of workpieces and a machine tool unit. According to said method, the workpieces are subjected to fine-hole drilling and precision finishing, preferably roller-burnishing or smoothing, a post-processing measurement is carried out and, depending on said measurement, the fine-hole drilling tool is adjusted.

A reaction tool for forming openings in an aircraft fuselage joint is provided. The joint includes (i) a first side from which a forming tool is to be applied at a plurality of opening locations and (ii) an opposing second side. The reaction tool includes a plurality of connectors configured to couple to the joint second side, and a reaction bar coupled to the plurality of connectors. The reaction bar is configured to extend across the plurality of opening locations. The reaction tool also includes a plurality of reaction members coupled to the reaction bar. Each of the reaction members includes a clamping surface configured to couple to the joint second side such that each clamping surface at least partially surrounds a corresponding one of the plurality of opening locations.