Chapter 7. SOLDERING

TM 750-245-4

CHAPTER 7

SOLDERING

Section I. INTRODUCTION

electrical connections. Material requirements and tools

7-1. General

are provided in system TM's.

a. This chapter contains requirements for soldering

of electrical and electronic equipment.

This information has been developed to increase the

7-2. Inspection Requirements

reliability of equipment undergoing repairs at direct

Inspection requirements will hold true only if the

support and general support shops. These concepts

inspector has a knowledge of proper soldering

have proven to be adequate for all fielded equipment.

techniques. He must also have a knowledge of proper

Harness layout, lacing, crimping of solderless

tools and materials available. The following sections

connectors, and terminations are contained in chapter 3,

should provide him with adequate inspection procedures

electrical and electronic equipment.

and acceptance criteria to evaluate and determine if

proper soldering repairs have been accomplished.

b. This chapter presents the instructions for

inspections of soldering to obtain high reliability

Section II. INSPECTION PROCEDURE

should be inspected in accordance

7-3. General

Many electrical chassis in the field were produced under

with paragraph 7-3.

standards that are no longer used for missile system

production. The inspector must know and recognize

7-5. Mechanical

these differences to preclude unnecessary rejection and

Mechanical check of a solder point is acceptable only

rework of chassis. These differences are:

when required to supplement a visual inspection. This

a. Wraps of conductor 270 degrees to 360 degrees

must be limited to a minor movement of component

around turret terminal were permitted, present

leads using only padded pliers or wooden soldering aid.

requirements are 180 degrees, but not more than 360

Care must be taken not to fracture delicate solder joints

degrees except multiple adjacent terminals.

or to break the component leads.

b. Bare copper ends were permitted; now

7-6. Surveillance

conductor ends must be covered by solder.

A surveillance program should be initiated jointly by the

c. Nicks on leads were permitted; padded tools

repair shop and QC inspection units. The primary

must now be used to form leads.

purpose of the surveillance program is to establish the

d. Slack in leads and vibration bends for mounting

standard operating procedures and standard inspection

of components were not required; these are now

procedures to assure that repaired materials will meet

required.

the designated purpose for tactical operations. The

e. Insulation clearance from the solder joint was

following areas should be included in the surveillance

not specified; see paragraph 7-10f.

program, but may vary depending upon: DS/ GS

mission

assignments,

tactical

situation,

and

7-4. Visual Inspection

geographical location.

All soldered connections shall be inspected for:

a. Housekeeping.

a. Adequate mechanical and solder application.

(1) Cleanliness of work area.

b. Cleanliness.

(2) Lighting of work area.

(1) Removal of rosin flux.

(3) Arrangement of work benches to test

equipment.

(2) Removal of solder splatter from adjacent

areas.

b. Control of Tools.

NOTE

(1) Correct tools to perform the specific

Solder connections other than those

soldering function.

made by the DS/GS repairman

(2) Proper use of soldering tools.

7-1