Circuit Board Repair Guide > Base Board Repair > 3.3.2 How to Repair Major Damage to Non-Plated Holes

How to Repair Major Damage to Non-Plated Holes

Repair Circuit Boards | Repair SMT Pads | Repair BGA Pads | Repair Lands | Repair Edge Contacts
Repair a Conductor | Plated Hole Repair | Base Board Repair | Replace Solder Mask or Coatings

This circuit board repair procedure is used to repair severe damage to a hole or to modify the size, shape or location of an unsupported tooling or mounting hole. The hole may have component leads, wires, fasteners, pins, terminals or other hardware running through it. This repair procedure uses a dowel of matching board material and high strength circuit board epoxy to secure the dowel in place. After the new material is bonded in place, a new hole can be drilled. This procedure can be used on single sided, double sided or multilayer printed circuit boards and printed circuit board assemblies.

Damaged inner-layer connections may require surface wire adds.
Non plated damaged hole in base board needs repair
Damaged Hole, Non Plated

IPC Acceptability References
IPC-A-600 2.0 Externally Observable Characteristics
IPC-A-610 10.0 Laminate Conditions
Related Procedure Reference
CTC 1.0 Foreword - Circuit Board Repair Guide
CTC 2.1 Handling Electronic Assemblies
CTC 2.2.1 How to Clean a Circuit Board
CTC 2.2.2 Cleaning Circuit Boards, Aqueous Batch Process
CTC 2.5 Baking and Preheating of Printed Circuit Boards
CTC 2.7 Epoxy Mixing and Handling
IPC 7721 3.3.2 Hole Repair, Transplant Method

Tools and Materials
Alcohol Swabs - Self-saturating Isopropyl alcohol swabs. Squeeze handle to release alcohol.
Circuit Bond Pack - Clear, superior strength epoxy in two-compartment plastic package.
Cleaner - General purpose cleaner for removing contamination.
Cleaning Brushes - Disposable brushes for use with solvents for cleaning and application of coatings.
End Mills - Designed for end cutting and hole boring.
File - High carbon steel needle file perfect for all kinds of detail work.
High Temperature Tape Discs - High temperature polyimide tape discs, .50" diameter.
Knife with #16 Blades - A must-have tool for precise cutting, scraping and trimming.
Microscope - It is a challenge to undertake precision repair without a good microscope.
Micro Drill System - Versatile power tool for milling, drilling, grinding, cutting and sanding circuit boards.
Ball Mills, Abrasives, Cutting Tools - Ball mills, abrasives and cutting tools for working on circuit boards.
Oven - General purpose oven for drying, baking and curing epoxies.
Precision Drill - Precision drill press for accuracy and controlled depth drilling.
Scraper - Hardened stainless steel tip for scraping solder mask and removing defects.
Wipes - Nonabrasive, low-linting wipes for cleanup.

3.3.2 Hole Repair, Transplant Method

Printed Board Type: R/W  |  Skill Level: Expert  |  Conformance Level: High  |  Rev.: E  |  Rev. Date: Jul 7, 2000

New hole milled to encompass damaged area

Figure 1: New hole is milled to encompass entire damaged area.

1.  Clean the area.
2.  Drill out the damaged or improperly sized hole using a carbide end mill or drill. Mill the hole using a precision drill press or milling machine for accuracy. The diameter of the cutting tool should be as small as possible yet still encompass the entire damaged area. (See Figures 1 and 2).
   Abrasion operations can generate electrostatic charges.
Precision Drill System for hole drilling and milling

Figure 2: Precision Drill System
for accurate hole drilling and milling.

3.  Cut a piece of replacement base material rod. Base material rod is made from FR-4 dowel stock. Cut the length approximately 12.0 mm (0.50") longer than needed.
4.  Clean the reworked area.
5.  Use High Temperature Tape to protect exposed parts of the circuit board bordering the rework area.
6.  Mix the epoxy.
Place replacement dowel and bond with epoxy

Figure 3: Place replacement dowel
in position and bond with epoxy.

7.  Coat both the dowel and the hole with epoxy and fit together. Apply additional epoxy around perimeter of new material. (See Figure 3). Remove excess epoxy.
8.  Cure the epoxy per Procedure 2.7 Epoxy Mixing and Handling.

Some components may be sensitive to high temperatures.
Cut off excess material and redrill holes

Figure 4: Cut off excess material
and redrill holes as required.

9.  Remove the tape and cut off the excess material using the razor saw. Mill or file the dowel flush with the board surface. (See Figure 4).
10. Complete the procedure by redrilling holes and adding circuitry as required.
(See Figure 4).

Apply surface coating to match prior coating as required.
Micro Drill System used for milling, drilling, grinding, cutting and sanding circuit boards

Figure 5: Micro Drill System.
11. Clean the reworked area.
1.  Visual and dimensional examination of the reworked area for conformance to drawings and specifications.

Special Order. Usually ships within 3 business days from Haverhill, MA, USA.   For customer service call 1-519-651-3060.

How to purchase.                                                           View cart Minimum order $50 + shipping
Image Description Part No., Price and Quantity
Alcohol Swab Alcohol Swabs (package of 50), 235-1000-50

Self-saturating foam swabs filled with 99% Isopropyl alcohol. Ideal for removing flux residue and cleaning surfaces prior to soldering, coating and application of epoxy. Overall Length: 4.125". Squeeze handle until it "pops" releasing alcohol into the tip.


$39.00 pkg/50

Liquid circuit board epoxy Circuit Bond Pack  MSDS, 115-3302

Clear, low viscosity, superior strength epoxy, precisely measured out into a two-compartment plastic package so it's easy to use and there's no measuring (2 gram). Shelf life: 6 months minimum.


$12.95 each

Cleaning Brush Cleaning Brushes (package of 100), 235-2106-100

Disposable brushes for use with solvents for cleaning and application of coatings.


$29.95 pkg/100

File 115-3132 File, 115-3132

High carbon steel needle file perfect for all kinds of detail work. File can be used to put the perfectly beveled edge on replacement gold edge contacts.


$9.95 each

High Temperature Tape Discs 235-3050 High Temp. Tape Discs, .50" Diameter, 235-3050

High temperature tape discs are made of polyimide film with 1.5 mil of silicone adhesive that will not leave any residue. They can withstand temperatures of up to 500°F (260°C).

US $5.95 pkg/60

Knife 355-0614 Knife with #16 Blades, 355-0614

A must-have tool for precise cutting, scraping and trimming. Includes five #16 blades.


$9.95 each

Scraper 335-3197 Scraper, 335-3197

Hardened stainless steel tip for scraping solder mask and removing defects.


$9.95 each


Products above ship direct from manufacturer and are special order/non-returnable. Will ship within 3 business days. Inc. is a payment facilitator for goods provided by ELAB (Engineering Lab). View cart

Payment methods accepted: American Express, Visa, MasterCard, Discover, Diners Club, JCB and Paypal.

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Import duties and Value Added Tax will be collected at time of delivery for all shipments outside the USA.

Links to Related Products

Professional Repair Kit used to repair damaged circuit boards   Professional Repair Kit 201-2100
This circuit board repair kit includes everything needed for a wide range of circuit board repair needs. The Professional Repair Kit is designed to be used for the following applications: surface mount and BGA pad repair, circuit and land repair, plated hole repair, gold edge contact repair, solder mask and base board repair. This is the most popular circuit board repair kit we sell.

Micro Drill System used for drilling, grinding, cutting circuit boards   Micro Drill System 110-4105
The Micro Drill System is a repair technician's dream and is ideal for milling, drilling, grinding, cutting and sanding circuit boards. It removes coating, cuts circuits, cuts leads, drills holes, cuts slots, shapes FR4 and performs many other procedures using various interchangeable bits. Unlike most hand-held tools, the Micro Drill has a tiny, high speed DC motor in the hand piece, eliminating cumbersome drive cables and giving you better control. A separate power supply keeps the hand piece lightweight and reduces operator fatigue. Base unit has controls for forward/reverse and speed up to 45,000 RPM.

Copyright and Disclaimer Notice    Phone: 1-519-651-3060    Ships From: Haverhill, MA 01835 USA

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