Cylinder Head Fully Threaded Self-Tapping Wood Screw
  • Code Approval
  • Connection Type
  • Wood/Wood
  • Applications
  • Timber Framing, Log Home Building, Mass & Heavy Timber Construction
  • Manufacturer
  • SWG

Request a Quote Tech. Support

Cylinder Head

Fully Threaded

Tapping Tip

Wood Reinforcement

Product Description

Product Description

The ASSY VG Cyl (Cylinder Head) screw is a fully threaded self-tapping wood screw engineered for timber reinforcement, beam repair, and connections where a small head is required for a clean, concealed, architectural finish.

Code-approved reliability, the ASSY VG Cyl screw has been awarded an ICC-ESR approval in the United States and the Canadian Construction Materials Centre Reports (CCMC) approval in Canada.  



Diameters 1/4″ (6 mm) , 5/16″ (8 mm) , 3/8″ (10 mm)
Lengths 3-1/8″ (80 mm)  to  31-1/2” (800 mm)
  • Small cylindrical head almost invisible when installed
  • Easily concealable with a wood plug
  • Zinc coating designed for dry service condition
  • Aggressive drill tip mimics a drill bit and bites into the wood and assures quick and easy installation
  • Ideal for incline wood-to-wood connections and wood reinforcement
  • Can be used in Timber Concrete Composite systems, potentially replacing ASSY VG CSK
  • For more connection examples and information see our Design Guides
  • All ASSY fasteners can participate in LEED BD+C 2.0 certification [MRc 4.1 & 4.2, 2 points possible] thanks to the percentage of post-consumer recycled steel used to manufacture them. LEED certification letter is available on request.

The range of available lengths and diameters makes the ASSY VG Cyl suitable for a broad range of projects from log home building to multi-story mass timber construction. The ASSY VG Cyl screw can also be used in beam upgrades and connections where a small screw head is required. ASSY fully threaded screws can be used in typical reinforcing applications, including checked or cracked members, potentially restoring them to nearly their full original strength following our Timber Reinforcement Guide.



SpecificationASSY VG CYLThread LengthAW Drive BitPackaging Qty.
# ItemMaterialHead
CYL0680Hardened Steel Cylinder Head1/4 x 3 1/86 x 802 7/873RW 30100
CYL06100Hardened Steel Cylinder Head1/4 x 46 x 1003 5/893RW 30100
CYL06120Hardened Steel Cylinder Head1/4 x 4 3/46 x 1204 1/2113RW 30100
CYL06140Hardened Steel Cylinder Head1/4 x 5 1/26 x 1405 1/4133RW 30100
CYL06160Hardened Steel Cylinder Head1/4 x 6 1/46 x 1606153RW 30100
CYL06180Hardened Steel Cylinder Head1/4 x 7 1/86 x 1806 3/4173RW 30100
CYL06200Hardened Steel Cylinder Head1/4 x 7 7/86 x 2007 5/8193RW 30100
CYL08120Hardened Steel Cylinder Head5/16 x 4 3/48 x 1204104RW 4050
CYL08140Hardened Steel Cylinder Head5/16 x 5 1/28 x 1404 7/8124RW 4050
CYL08160Hardened Steel Cylinder Head5/16 x 6 1/48 x 1605 5/8144RW 4050
CYL08180Hardened Steel Cylinder Head5/16 x 7 1/88 x 1806 1/2164RW 4050
CYL08200Hardened Steel Cylinder Head5/16 x 7 7/88 x 2007 1/4184RW 4075
CYL08220Hardened Steel Cylinder Head5/16 x 8 5/88 x 2208204RW 4075
CYL08240Hardened Steel Cylinder Head5/16 x 9 1/28 x 2408 7/8224RW 4075
CYL08260Hardened Steel Cylinder Head5/16 x 10 1/48 x 2609 5/8244RW 4075
CYL08280Hardened Steel Cylinder Head5/16 x 118 x 28010 3/8264RW 4075
CYL08300Hardened Steel Cylinder Head5/16 x 11 7/88 x 30011 1/8284RW 4075
CYL08330Hardened Steel Cylinder Head5/16 x 138 x 33012 3/8314RW 4050
CYL08360Hardened Steel Cylinder Head5/16 x 14 1/48 x 36013 1/2344RW 4050
CYL08380Hardened Steel Cylinder Head5/16 x 158 x 38014 3/8364RW 4050
CYL08430Hardened Steel Cylinder Head5/16 x 178 x 43016 1/4414RW 4025
CYL08480Hardened Steel Cylinder Head5/16 x 198 x 48018 1/4464RW 4025
CYL08530Hardened Steel Cylinder Head5/16 x 20 7/88 x 53020 1/4514RW 4025
CYL08580Hardened Steel Cylinder Head5/16 x 22 7/88 x 58022 1/4564RW 4025
CYL10180Hardened Steel Cylinder Head3/8 x 7 1/810 x 1806 1/2165RW 5050
CYL10200Hardened Steel Cylinder Head3/8 x 7 7/810 x 2007 1/4185RW 5050
CYL10220Hardened Steel Cylinder Head3/8 x 8 5/810 x 2208 1/8205RW 5050
CYL10240Hardened Steel Cylinder Head3/8 x 9 1/210 x 2408 7/8225RW 5050
CYL10260Hardened Steel Cylinder Head3/8 x 10 1/410 x 2609 5/8245RW 5050
CYL10280Hardened Steel Cylinder Head3/8 x 1110 x 28010 3/8265RW 5050
CYL10300Hardened Steel Cylinder Head3/8 x 11 7/810 x 30011 1/4285RW 5050
CYL10320Hardened Steel Cylinder Head3/8 x 12 5/810 x 32012305RW 5050
CYL10340Hardened Steel Cylinder Head3/8 x 13 3/810 x 34012 3/4325RW 5050
CYL10360Hardened Steel Cylinder Head3/8 x 14 1/410 x 36013 5/8345RW 5050
CYL10380Hardened Steel Cylinder Head3/8 x 1510 x 38014 3/8365RW 5050
CYL10400Hardened Steel Cylinder Head3/8 x 15 3/410 x 40015 1/8385RW 5050
CYL10430Hardened Steel Cylinder Head3/8 x 1710 x 43016 3/8415RW 5025
CYL10480Hardened Steel Cylinder Head3/8 x 1910 x 48018456RW 5025
CYL10530Hardened Steel Cylinder Head3/8 x 20 7/810 x 53019 7/8506RW 5025
CYL10580Hardened Steel Cylinder Head3/8 x 22 7/810 x 58021 7/8556RW 5025
CYL10650Hardened Steel Cylinder Head3/8 x 25 5/810 x 65024 5/8626RW 5025
CYL10700Hardened Steel Cylinder Head3/8 x 27 5/810 x 70026 5/8676RW 5025
CYL10750Hardened Steel Cylinder Head3/8 x 29 1/210 x 75028 5/8726RW 5025
CYL10800Hardened Steel Cylinder Head3/8 x 31 1/210 x 80030 1/2776RW 5025
CAD Drawings

2D & 3D Geometry

ProductASSY VG CYL Diameter File Extension
Design Guides

Design Guides

Structural Screw Catalog

A catalog with all information on our ICC & CCMC code-approved fasteners, including dimensions, references & design properties.

Structural Screw Connection Design Guide

Companion to the Structural Screws Catalog, it provides easy-to-read tables for the most common mass timber connections with design values & installation instructions.

Code Approvals

Code Approvals

ICC Code Approval ESR 3178 for Fully Threaded Screws - 2023 Edition

CCMC Code Approval 13677-R

ISO 50001 Certification for ASSY Fasteners

LA Research Report (LARR): RR 26072

White Papers

White Papers

Supplementary Considerations for the Conventional Yield Model

Screw Buckling Values for Compression Perpendicular to Grain Reinforcement

Withdrawal Resistances of ASSY Screws at Various Angles to the Grain

Timber Reinforcement Guide

Designing Timber Concrete Composite Systems (TCC) with ASSY Self-Tapping Screws

Purlin to Beam Connections Using ASSY Fully Threaded Fasteners

Roof-to-Wall Connections (Truss Uplift)

ASSY Screws vs. Lag Bolt

Timber Moisture Content Changes and Associated Stress Predictions on Structural Wood Screws

Technical Blogs

Technical Blogs

    Stay informed with MTC Newsletter

    Request a Quote

    Provide your contact information and the quantity and size you would like, and our Product Consultants will contact you with a quote for your requirements.

    Contact tech Support

    Provide your contact information , our Engineers will get back to you within 48hrs.

    Sign Up

    Register for a Technical Learning Session


    Sign up for MTC Newsletter and keep up to date with all our progress.