IPC-7721(S).pdf - 第154页
NOTES IPC-7721 Number: 5.2 Revision: Date: 2/98 Subject: Plated Hole Repair , Double Wall Method P a g e4o f4
EVALUATION
1. Visual examination, dimensional requirement of pad diameter and inside diam-
eter.
2. Electrical continuity measurement.
IPC-7721
Number: 5.2
Revision:
Date: 2/98
Subject: Plated Hole Repair, Double Wall Method
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NOTES
IPC-7721
Number: 5.2
Revision:
Date: 2/98
Subject: Plated Hole Repair, Double Wall Method
Page4of4
OUTLINE
This procedure describes the use of flat set eyelets for the repair of a through con-
nection that has an inner layer connect, no surface wire is used. The inner layer
reconnect is established by soldering the barrel of an eyelet to the exposed inner
layer and the connection is encapsulated in high strength epoxy.
CAUTION
This is a complex repair procedure that demands the proper tools and materials. To
expect reliable results, repair technicians must have a high level of expertise. Use this
method only when alternative methods are unacceptable.
CAUTION
This procedure requires very accurate control over the location and depth of a milled
hole. It is recommended that a precision drill system be used in combination with a
high power stereo microscope.
REFERENCES
2.1 Handling Electronic Assemblies
2.2 Cleaning
TOOLS & MATERIALS
Ball Mills, Carbide
Buffer
Caliper
Cleaner
End Mills, Carbide
Eyelets
Eyelet Press System
Eyelet Repair Kit
Eyelet Setting Tools
Hand Held Drill
Liquid Flux
Knife
Microscope
Pin Gauges
Precision Drill Press
Solder
Solder Iron
Wipes
EYELET SELECTION CRITERIA
Figure 1 Drill press shown with PC
board pinned in place.
Figure 2 Mill down to and expose
inner layer signal or plane.
Figure 3 Solder the eyelet barrel to
the exposed inner layer.
Figure 4 Fill the milled hole with the
epoxy.
7721
Repair and
Modification of
Printed Boards and
Electronic Assemblies
Revision:
Date: 2/98
Plated Hole Repair,
Inner Layer Connection
Number: 5.3
Product Class: R
Skill Level: Expert
Level of Conformance: Medium
Material in this manual was voluntarily established by Technical Committees of the IPC. This material is advisory only and its
use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the use, application, or adaptation of this
material. Users are also wholly responsible for protecting themselves against all claims or liabilities for patent infringement.
Equipment referenced is for the convenience of the user and does not imply endorsement by the ipc.
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