Inquire: Call 0086-755-23203480, or reach out via the form below/your sales contact to discuss our design, manufacturing, and assembly capabilities.
Quote: Email your PCB files to Sales@pcbsync.com (Preferred for large files) or submit online. We will contact you promptly. Please ensure your email is correct.
Notes: For PCB fabrication, we require PCB design file in Gerber RS-274X format (most preferred), *.PCB/DDB (Protel, inform your program version) format or *.BRD (Eagle) format. For PCB assembly, we require PCB design file in above mentioned format, drilling file and BOM. Click to download BOM template To avoid file missing, please include all files into one folder and compress it into .zip or .rar format.
When you’re standing at an inspection station trying to decide if a through-hole solder joint passes or fails, the last thing you want is ambiguity. Is that barrel fill sufficient for Class 2? Does that wetting angle meet spec? Is that dull surface a defect or just lead-free solder doing what lead-free solder does?
That’s exactly why IPC developed IPC-DRM-PTH. This compact training and reference guide puts through-hole solder joint acceptance criteria right at your fingertips—on the shop floor, in the training room, or wherever accept/reject decisions happen. It’s not meant to replace IPC-A-610 or J-STD-001, but rather to distill the most critical PTH criteria into a visual, easy-to-use format that inspectors and operators can reference quickly.
I’ve used IPC-DRM-PTH for years in training programs and as a shop floor reference. At 30 pages in a spiral-bound format, it fits in a tool drawer or sits open on a workbench without falling apart. This guide covers what IPC-DRM-PTH includes, how to use it effectively, and why it’s become a staple in electronics manufacturing training programs.
What is IPC-DRM-PTH?
IPC-DRM-PTH stands for “Desk Reference Manual – Plated Through-Hole.” It’s a training and reference guide published by IPC that illustrates acceptance criteria for through-hole solder connections based on IPC-A-610, the industry’s primary standard for electronic assembly acceptability.
The guide uses computer-generated color illustrations and high-quality photographs to show what acceptable and defective through-hole solder joints look like. Each illustration shows the joint from multiple perspectives—component side, barrel cross-section, and solder side—so inspectors can understand the three-dimensional nature of PTH solder joints.
IPC-DRM-PTH Key Information
Attribute
Details
Full Title
Through-Hole Solder Joint Evaluation Training & Reference Guide
Document Number
IPC-DRM-PTH
Current Revision
Revision G (aligned with IPC-A-610G)
Format
Spiral-bound, 5.5 x 8.5 inch (14 x 21.5 cm)
Page Count
Approximately 30 pages
Languages
English, German, Chinese, and others
Reference Standard
IPC-A-610 Rev G
IPC-DRM-PTH Revision History
The guide is updated to align with new revisions of IPC-A-610:
Revision
Release
Aligned With
Rev A
1997
IPC-A-610A
Rev B
1999
IPC-A-610B
Rev C
1999
IPC-A-610C
Rev D
2005
IPC-A-610D
Rev E
2010
IPC-A-610E
Rev F
2015
IPC-A-610F
Rev G
2018
IPC-A-610G
Rev H (QRG-PTH)
2021
IPC-A-610H
Note: Starting with Rev H, IPC renamed the series to “QRG” (Quick Reference Guide) instead of “DRM” (Desk Reference Manual), but the content and purpose remain the same.
What IPC-DRM-PTH Covers
The guide focuses specifically on plated through-hole solder connections—joints where component leads pass through holes in the PCB and are soldered on the opposite side. It doesn’t cover surface mount technology (that’s IPC-DRM-SMT) or terminal connections.
Topics Covered in IPC-DRM-PTH
Topic
Description
Land Coverage
Solder coverage on the pad/land around the hole
Vertical Fill
How much solder fills the barrel from source to destination side
Wetting of Lead
Solder adhesion to the component lead
Wetting of Barrel
Solder adhesion to the plated hole wall
Wetting of Land
Solder adhesion to the pad surface
Contact Angle
The angle where solder meets the base metal
Excess Solder
Too much solder on the joint
Insufficient Solder
Not enough solder on the joint
Solder Bridging
Unintended solder connections between conductors
Cold Solder Joints
Grainy, disturbed, or poorly formed joints
Nonwetting
Solder doesn’t adhere to surfaces
Dewetting
Solder recedes after initial wetting
Lead Protrusion
How far the lead extends beyond the solder
Disturbed Joints
Evidence of movement during solidification
Fractured Joints
Cracks in the solder connection
Solder Balls
Loose spheres of solder
Solder Splashes/Webbing
Unintended solder on surfaces
Voids and Blowholes
Cavities in the solder joint
Residue
Flux or other contamination
PTH Solder Joint Anatomy
IPC-DRM-PTH uses consistent terminology to describe through-hole joints. Understanding this terminology is essential for using the guide effectively:
Solder Source Side: The side where solder is applied (typically the bottom during wave soldering)
Solder Destination Side: The opposite side where solder flows through the barrel (typically the top/component side)
Barrel: The plated wall of the hole through the PCB
Land/Pad: The copper area surrounding the hole on each side
Fillet: The concave meniscus of solder that forms between the lead and the land
Lead: The component terminal that passes through the hole
IPC-DRM-PTH Class 1, 2, and 3 Requirements
Like all IPC acceptance documents, IPC-DRM-PTH presents criteria for three product classes. The guide uses color-coded bars to indicate which class(es) each acceptance level applies to.
Understanding IPC Classes in IPC-DRM-PTH
Class
Name
Description
Typical Applications
Class 1
General Electronic Products
Function is primary requirement
Consumer electronics, toys, non-critical devices
Class 2
Dedicated Service Electronic Products
Extended life and reliable performance required
Industrial equipment, telecom, computers
Class 3
High-Performance Electronic Products
Continued performance critical, no downtime tolerated
Aerospace, medical, military
Vertical Fill Requirements by Class
One of the most referenced criteria in IPC-DRM-PTH is vertical fill—how much of the barrel must be filled with solder. This is critical because adequate fill ensures mechanical strength and electrical reliability.
Measurement
Class 1
Class 2
Class 3
Minimum Vertical Fill
75%
75%
75%
Circumferential Wetting (Source Side)
180°
270°
330°
Circumferential Wetting (Destination Side)
180°
180°
270°
Important Notes:
Vertical fill is measured from the solder source side toward the destination side
The fill must be continuous (no circumferential voids that separate source and destination side solder)
For supported holes (with internal plane connections), requirements may differ
Wetting Requirements
Good solder joints require proper wetting—the solder must adhere uniformly to all metal surfaces. IPC-DRM-PTH illustrates acceptable wetting conditions:
Surface
Requirement
Lead
Evidence of wetting; solder outline follows lead contour
Barrel
Solder wets plated barrel wall
Land (Source Side)
Fillet with concave surface showing good wetting
Land (Destination Side)
Evidence of wetting; fillet may be smaller
Key PTH Solder Defects Illustrated in IPC-DRM-PTH
The guide provides photographs and illustrations of common defects, making it easier to identify problems during inspection.
Solder Joint Defects Summary
Defect
Description
Visual Indicators
Insufficient Solder
Not enough solder to form proper joint
No fillet, lead outline too visible, incomplete fill
Excess Solder
Too much solder obscuring the joint
Lead contour not visible, convex fillet, potential bridging
Cold Joint
Disturbed or improperly formed solder
Grainy texture, dull surface, irregular shape
Nonwetting
Solder doesn’t adhere to surface
Visible basis metal, solder beads up
Dewetting
Solder recedes after initial wetting
Irregular covered areas, exposed metal between solder regions
Solder Bridge
Unintended connection between conductors
Solder spans gap to adjacent land or conductor
Disturbed Joint
Movement during solidification
Cracked appearance, rough surface, possible fracture
Fracture
Crack in the solder connection
Visible crack line, possible separation
Void/Blowhole
Cavity in the solder
Visible hole or depression in solder surface
Solder Ball
Loose sphere of solder
Free solder ball on board surface
Lead-Free vs. Tin-Lead Solder Appearance
IPC-DRM-PTH addresses an important issue that confuses many inspectors: lead-free solder looks different from traditional tin-lead solder, but this doesn’t necessarily indicate a defect.
Characteristic
Tin-Lead Solder
Lead-Free Solder
Surface Finish
Bright, shiny
May be dull, matte, or grainy
Contact Angle
Generally lower
May be higher (steeper)
Surface Texture
Smooth
May show graininess or texture
Color
Silver-bright
May appear slightly different hue
The guide emphasizes that surface appearance alone doesn’t determine acceptability for lead-free joints—wetting, coverage, and fill are still the primary criteria.
IPC-DRM-PTH vs. IPC-DRM-SMT: Understanding the Difference
IPC publishes two primary solder evaluation desk reference manuals. Understanding which one to use is important for training and inspection programs.
Comparison: IPC-DRM-PTH vs. IPC-DRM-SMT
Aspect
IPC-DRM-PTH
IPC-DRM-SMT
Full Name
Through-Hole Solder Joint Evaluation
Surface Mount Solder Joint Evaluation
Focus
Plated through-hole connections
SMT components (chip, gull wing, J-lead, BGA)
Page Count
~30 pages
~44 pages
Joint Types
PTH barrel fill, lead wetting
Fillet dimensions, heel/toe/side fillets
Key Criteria
Vertical fill, circumferential wetting
Maximum/minimum side overhang, fillet height
Component Types
Axial, radial, DIP, connectors
Chip resistors/caps, QFP, SOIC, BGA
Reference Standard
IPC-A-610 Chapter 7
IPC-A-610 Chapter 8
When to Use Each Guide
Use IPC-DRM-PTH when:
Inspecting wave-soldered assemblies
Evaluating hand-soldered through-hole connections
Training operators on PTH component assembly
Mixed technology boards (for the PTH portion)
Use IPC-DRM-SMT when:
Inspecting reflow-soldered assemblies
Evaluating chip components, leaded SMT, BGAs
Training operators on SMT placement
Mixed technology boards (for the SMT portion)
Use Both when:
Mixed technology assembly operations
Comprehensive inspector training programs
Quality systems covering all assembly types
How IPC-DRM-PTH Relates to IPC-A-610 and J-STD-001
IPC-DRM-PTH doesn’t replace IPC-A-610 or J-STD-001—it supplements them by providing quick visual reference to specific criteria.
Relationship Between Standards
Document
Purpose
Role
IPC-A-610
Acceptability of Electronic Assemblies
Complete acceptance standard with all criteria
J-STD-001
Requirements for Soldered Electrical and Electronic Assemblies
Process and materials requirements
IPC-DRM-PTH
Through-Hole Solder Joint Evaluation Training & Reference Guide
Quick reference to PTH visual criteria
Cross-References in IPC-DRM-PTH
Each acceptance criterion in IPC-DRM-PTH includes references to the corresponding sections in IPC-A-610. For example:
Vertical fill criteria reference IPC-A-610 Table 7-3
Wetting criteria reference IPC-A-610 Figures 7-71 through 7-77
While there’s no specific IPC-DRM-PTH certification, the guide supports training for:
Certification
Description
IPC-A-610 CIS
Certified IPC Specialist for Assembly Acceptability
IPC-A-610 CIT
Certified IPC Trainer for Assembly Acceptability
J-STD-001 CIS
Certified IPC Specialist for Soldering
J-STD-001 CIT
Certified IPC Trainer for Soldering
Frequently Asked Questions About IPC-DRM-PTH
Is IPC-DRM-PTH a standard or a training guide?
IPC-DRM-PTH is a training and reference guide, not a standard. It doesn’t establish requirements—it illustrates requirements from IPC-A-610, the actual acceptance standard. Think of IPC-DRM-PTH as a visual quick-reference tool that helps inspectors and operators understand and apply IPC-A-610 criteria. The guide explicitly states it doesn’t take precedence over IPC-A-610 or other contractual requirements.
Do I need IPC-DRM-PTH if I already have IPC-A-610?
IPC-A-610 is comprehensive but can be overwhelming when you need a quick answer at an inspection station. IPC-DRM-PTH distills the through-hole criteria into 30 focused pages with clear illustrations and photographs. Many operations use both: IPC-A-610 as the authoritative reference and IPC-DRM-PTH as the shop-floor quick reference. The compact, spiral-bound format of IPC-DRM-PTH makes it practical for workstation use in ways that the larger IPC-A-610 isn’t.
How often is IPC-DRM-PTH updated?
IPC-DRM-PTH is updated when IPC-A-610 is revised, which typically happens every 3-5 years. The guide revision letter corresponds to the IPC-A-610 revision it supports (e.g., IPC-DRM-PTH-G supports IPC-A-610G). When a new revision releases, update your training materials and shop floor references to ensure inspectors are using current criteria. IPC allows a transition period for adopting new revisions.
Can I use IPC-DRM-PTH for lead-free soldering inspection?
Yes, IPC-DRM-PTH includes information about lead-free solder appearance and explicitly addresses how lead-free joints may look different from tin-lead joints. The guide notes that lead-free solder may appear duller, grainier, or have higher contact angles than tin-lead—without these appearances being defects. The acceptance criteria (wetting, fill, coverage) remain the same regardless of solder alloy. Understanding these visual differences is critical for inspectors working with lead-free processes.
What’s the difference between IPC-DRM-PTH and IPC-QRG-PTH?
They’re essentially the same product with different naming. Starting with the revision aligned to IPC-A-610H, IPC renamed the series from “DRM” (Desk Reference Manual) to “QRG” (Quick Reference Guide). The content, format, and purpose remain unchanged. If you’re purchasing the current version, you may see it listed as IPC-QRG-PTH-H. Both DRM and QRG designations refer to the same training and reference guide product line.
Conclusion
IPC-DRM-PTH serves a specific but important role in electronics manufacturing quality systems. It’s not meant to replace IPC-A-610—it’s meant to make IPC-A-610’s through-hole criteria accessible and usable on the shop floor.
The strength of IPC-DRM-PTH is its focused, visual approach. When an inspector needs to quickly verify whether a solder joint meets Class 2 barrel fill requirements, flipping through 30 illustrated pages is faster than searching through the hundreds of pages in IPC-A-610. When a trainer needs to explain what dewetting looks like versus nonwetting, the side-by-side photographs in IPC-DRM-PTH communicate more clearly than text alone.
For operations that perform through-hole soldering—whether wave, selective, or hand soldering—IPC-DRM-PTH should be part of your training toolkit. Combine it with IPC-DRM-SMT for mixed technology operations. Use both in conjunction with formal IPC-A-610 training for comprehensive inspector development.
The investment is minimal (under $50 per copy), and the payback comes in faster training, more consistent inspection decisions, and fewer disputes about what constitutes an acceptable through-hole solder joint. For quality engineers building inspection programs, IPC-DRM-PTH is a practical tool that bridges the gap between standards knowledge and shop floor application.
If you’re responsible for PTH inspection training or quality, obtain the current revision of IPC-DRM-PTH and integrate it into your programs. Your inspectors and operators will thank you for giving them a tool that makes their accept/reject decisions clearer and more confident.
Inquire: Call 0086-755-23203480, or reach out via the form below/your sales contact to discuss our design, manufacturing, and assembly capabilities.
Quote: Email your PCB files to Sales@pcbsync.com (Preferred for large files) or submit online. We will contact you promptly. Please ensure your email is correct.
Notes: For PCB fabrication, we require PCB design file in Gerber RS-274X format (most preferred), *.PCB/DDB (Protel, inform your program version) format or *.BRD (Eagle) format. For PCB assembly, we require PCB design file in above mentioned format, drilling file and BOM. Click to download BOM template To avoid file missing, please include all files into one folder and compress it into .zip or .rar format.
