Chem-Set CCH731 1/4-20 Flat Washer

Description

CCH731 washer is a Chem-Set 1/4-20 flat washer used with sink mounting and no-drill fastening hardware in countertop fabrication. It gives installers a simple bearing surface for wingnuts, clips, and bonded or mechanical anchors used under stone, quartz, solid surface, and related countertop materials.

CCH731 Washer Benefits

• Flat washer profile spreads clamp load across the connected hardware instead of concentrating force at one point.
• 1/4-20 hardware fit supports common Chem-Set sink clips, wingnuts, Keep-Nut posts, and bonded stud assemblies.
• Small replacement part helps shops keep undermount sink installs moving without breaking up a full kit.
• Useful as bench stock for service calls, repair kits, and fabrication crews that install sinks daily.
• Simple hardware format makes inspection easy before the clip is tightened under the countertop.

Use this washer when the mounting assembly calls for 1/4-20 hardware and a flat bearing face under the nut or clip. The washer is not the anchor by itself, but it helps the fastener stack load cleanly after the bonded stud, Keep-Nut post, or other threaded attachment is in place.

Where CCH731 Washer Fits

• Undermount sink clip assemblies on granite, quartz, engineered stone, and solid surface countertops.
• Chem-Set no-drill stud systems paired with adhesive and sink clips.
• Keep-Nut based installs that use 1/4-20 threaded posts and washers.
• Repair work where a missing washer is preventing proper clamp-up.
• Shop hardware bins for countertop install teams and punch-list crews.

Surface Preparation and Use

Confirm that the anchor or stud has cured or seated according to the installation method before tightening the washer stack. Remove stone dust, adhesive squeeze-out, or metal chips from the washer area so the hardware sits flat. Tighten only enough to secure the clip and sink rail without bending the clip or loading the stone edge unevenly.

For adhesive-bonded hardware, washer installation happens after the bond has reached handling strength. For mechanical inserts, confirm the insert is fully set before adding the washer, clip, and nut. Replace damaged washers rather than reusing pieces that are bent, cupped, or contaminated with cured adhesive.

Technical Details and Documentation

Chemical Concepts lists this item as a Chem-Set 731 1/4 USS flat washer with SKU CCH731 for 1/4-20 thread hardware. Related Chemical Concepts sink and fastener references show CCH731 washers used with CCH732G clips, wingnuts, Keep-Nut posts, and adhesive-mounted M1 fasteners. For broader fastener reference, review the Industrial Fasteners Institute.

Ordering Help

For related clips, posts, nuts, bonded fasteners, and install tools, browse Chemical Concepts fasteners. For help matching washers to sink clips or anchor kits, call (800) 220-1966 or email [email protected].