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Tight Tolerance Shoulder Screws
Tight Tolerance Smooth Head Shoulder Screws are available in Standard Profile, Low Profile, and Ultra Low Profile Head heights.

Standard-Inch

Tight Tolerance Smooth Head Shoulder Screws are also known as Smooth Head Screws and Precision Grade Shoulder Screws. Smooth Head screws are used as fasteners joining two pieces of an assembly where maintaining alignment is critical. These screws have an unthreaded shoulder made with an undersized tolerance to fit bearings, linear motion bushings, and other precision components. Some product applications are: imaging equipment, surgical tools, measuring devices, laboratory instruments, enclosures, and optical fixtures. Screws are machined with hex socket, slotted and 6-lobe drives on precise unmarked smooth heads, with an undercut portion between the thread and shoulder to allow a close fit. The shoulder diameter tolerance is held to +0 to -.001 inches and the shoulder length tolerance is +.002 to -0 inches. Tight tolerance screws have a Class 2A thread fit for inch.

Standard-Metric

These are manufactured for mechanical and electronic applications. Screws have shoulders that are held to precise diameter. All product is turned (not headed or forged) on our advanced Swiss Lathes, and we produce the finest looking parts available today. Each bolt is manufactured in one complete operation, which produces a tightly controlled, consistent, and concentric product. Extra care is taken in our cleaning and packaging processes to protect the product after it is manufactured, so they arrive at your door looking like jewelry. Shoulder length tolerance is +.05mm to -0mm. Screws have a Class 6g thread fit.

Friction Resistant Smooth Head-Inch

Brass shoulder screws are electrically conductive, nonmagnetic, and have good corrosion resistance. Use them where precision matters, such as in measuring devices, optical fixtures, and laboratory equipment. Screws are machined with hex socket, slotted and 6-lobe drives on precise unmarked smooth heads, with an undercut portion between the thread and shoulder to allow a close fit. The shoulder diameter tolerance is held to +0 to -.001 inches and the shoulder length tolerance is +.002 to -0 inches. Tight tolerance screws have a Class 2A thread fit for inch.

Friction Resistant Smooth Head-Metric

Brass shoulder screws are electrically conductive, nonmagnetic, and have good corrosion resistance. Use them where precision matters, such as in measuring devices, optical fixtures, and laboratory equipment. Shoulder length tolerance is +.05mm to -0mm. Screws have a Class 6g thread fit.

Extended Thread Smooth Head - Inch

These specialty shoulder screws have thread lengths that are twice as long as standard smooth head shoulder screws. Longer thread lengths are provided to facilitate fastening of materials using a hex nut and washer. Screws have the same thread fit as standard nuts and other than additional thread length, these screws are dimensionally the same as other smooth head shoulder screws.

Screws are machined with hex socket drive, unmarked smooth heads, and an undercut portion between the thread and shoulder, allowing a close fit. The shoulder tolerance is held to +0 to -.001 inches and the shoulder diameter is held to +.002 to -0 inches. Screws have a Class 2A thread fit.

Mil Spec Smooth Head - Inch

Precision shoulder screws were originally developed for use as the mechanical component in linear motion assemblies, and used to anchor bearings, gears, pulleys, etc. Precision shoulder screws manufactured in the USA to MS51575 for slotted shoulder screws, and MS51576 for socket drive shoulder screws. The military specification allows a wide range of head dimensions, according to the manufacturer's design. We have chosen to produce heads that are in the middle of the allowable range. You can find smaller heads in our "Low Profile" section. Passivated per QQ-P-35. Screws have a shoulder diameter tolerance of +0 to -.001 inch and a shoulder length tolerance of +.003 to -0 inches. Screws have a Class 2A thread fit.

Low Profile Smooth Head-Inch

The shallow head makes these screws the right size to hold components in tight spaces. Low Profile screws are 2/3 the head height of standard head height shoulder screws. The shoulder diameters are held to the same precise tolerance as other smooth head screws, at +0 to -.001 inches and the shoulder length tolerance is +.002 to -0 inches. All screws have a Class 2A thread fit.

Low Profile Smooth Head-Metric

The shallow head makes these screws the right size to hold components in tight spaces. Low Profile screws are 2/3 the head height of standard head height shoulder screws. Shoulder diameters are held to the same precise tolerance as other smooth head screws, at +0mm to -.025mm. Shoulder length tolerance is +.05mm to -0mm. All screws have a Class 6g thread fit.

Friction Resistant Low Profile - Inch

Brass shoulder screws are electrically conductive, nonmagnetic, and have good corrosion resistance. The shallow head makes these screws the right size to hold components in tight spaces. Low Profile screws are 2/3 the head height of standard head height shoulder screws. The shoulder diameters are held to the same precise tolerance as other smooth head screws, at +0 to -.001 inches and the shoulder length tolerance is +.002 to -0 inches. All screws have a Class 2A thread fit.

Ultra Low Profile Smooth Head-Inch

The shallow head makes these screws the right size to hold components in tight spaces. Ultra Low Profile screws are 1/3 the head height of standard head height shoulder screws. Shoulder diameters are held to the same precise tolerance as other smooth head screws, at +0 to -.001 inches. Shoulder length tolerance is +.002 to -0 inches. All screws have a Class 2A thread fit.

Ultra Low Profile Smooth Head-Metric

The shallow head makes these screws the right size to hold components in tight spaces. Ultra Low Profile screws are 1/3 the head height of standard head height shoulder screws. Shoulder diameters are held to the same precise tolerance as other smooth head screws, at +0 to -.025mm. Shoulder length tolerance is +.05 to -0mm. All screws have a Class 6g thread fit.
APEX FASTENERS, Inc - 15858 Business Center Drive - Irwindale, CA 91706 USA
APEX Fasteners supplies standard and custom screws, nut retainers, shoulder screws, plastites and taptites, all types of rivets, spring steel fasteners and special stampings, sems screws in standard, fractional or metric to electronics, aviation and other OEM industries worldwide. ApexFasteners.com custom manufactures screw machine components for electronic enclosure hardware as well as cold forming and cold headed specials for assembly and production requirements.
Tel: (626) 962-2219 - info@apexfasteners.com
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