Furniture Connector JCB Bolts

Furniture Connector JCB Bolts are the demountable fastener at the heart of every knock-down flat-pack design - the visible fixing in a flat-pack wardrobe, kitchen carcase, bed frame or shop fitting. The flat head sits in a counterbored hole on the show face, the shank passes through the panel, and the threads engage a barrel nut in a cross-bored hole in the mating piece. Together the JCB + barrel nut combination pulls two panels tight, can be disassembled and re-assembled many times, and leaves a clean show face. M6 and M8 are the only sizes we stock - matching the panel thicknesses (16mm and 18mm) standard in Australian cabinetmaking.

Also known as: JCB bolt, JCB connector bolt, furniture connector bolt, hex socket flat-head connector bolt, furniture assembly bolt, knock-down bolt, KD bolt, flat-pack bolt.

JCB connector bolts use metric coarse threads (ISO 261) - M6 standard pitch 1.0mm, M8 standard pitch 1.25mm. The shank is fully threaded so the full embedded length engages the barrel nut. Distinguished from a standard socket-head cap screw by the flat low-profile head designed to sit flush in a counterbored hole, and from a coach bolt by the internal hex (Allen) drive rather than a square neck.

GRADES AND MATERIALS

Nickel Plated Class 4.6 Carbon Steel - the standard finish for indoor cabinetry. Class 4.6 gives 400 MPa tensile strength and 240 MPa yield - more than adequate for furniture assembly loads. The nickel plating is a thin (5-10 micron) bright-silver decorative finish, indoor use only.

Stainless Steel A2-70 G304 - upgrade for outdoor furniture, kitchens, bathrooms or anywhere the joint might see moisture. 700 MPa tensile, corrosion-resistant, largely non-magnetic (why). Costs more than nickel plated but is the correct choice in wet service.

DRIVE AND INSTALLATION

JCB bolts use Internal Hex (Allen) drive - M6 takes a 4mm hex key, M8 takes a 5mm hex key. Both are standard sizes in any hex-key set. To install:

1. Drill the panel for the JCB shank (6.5mm for M6, 8.5mm for M8) and the mating piece for the barrel nut (10mm cross-bore for M6 barrel, 12mm for M8).
2. Drop the barrel nut into its cross-bored hole and rotate it so the threads align with the panel hole.
3. Pass the JCB bolt through the panel and engage the barrel nut threads by hand for the first few turns.
4. Tighten with the hex key until the panels pull tight. Don't over-torque - the timber will compress before the bolt fails.

Hex keys and T-handle drivers in matching sizes are in our Driving range.

A NOTE ON GALLING

Stainless A2-70 JCB bolts can gall (cold-weld) if assembled at high speed with an impact driver. Tighten by hand or with a slow speed driver for the first few turns; a smear of anti-seize on the threads helps. If a stainless bolt locks up before the head seats, back it out before forcing - galled threads are not recoverable.

COMMON APPLICATIONS

JCB connector bolts are the standard fastener for:

• Knock-down (KD) wardrobes and bedroom furniture - the entire reason flat-pack works. JCB + barrel pulls panels tight on assembly, releases for disassembly when the customer moves house.
• Kitchen carcase assembly - cabinet sides bolted to bases, plinths bolted to base units, end panels bolted to gables. Most pre-drilled supplier kits ship with M6 JCB + matching barrel nuts.
• Shop and office fitouts - demountable shelving, modular display units, partition walls. The ability to disassemble for relocation is the deciding factor over screwed-and-glued joints.
• Bed frame assembly - side rails to head and foot boards, slat supports to rails. M8 JCBs handle the higher loads on bed frames; M6 is fine for lighter pieces.
• Repair and restoration - replacing stripped or lost JCB hardware on second-hand flat-pack furniture is a common service call. The standard sizing means most replacements are off-the-shelf.

THREAD LENGTH AND MEASUREMENTS

The renderer auto-emits the per-SKU dimensions table from the product master on the live page. Length, thread length, drive size, head dimensions and pack quantity are all populated row-by-row when the SEO file goes live - no need to duplicate that data here. Use the table on the live page to confirm the exact SKU you need.

WHY AUSTRALIA TRUSTS BOLT & NUT

With 15+ years selling fasteners online from Brisbane, we hold over 25,000 stock lines and 200 million pieces - 98.75% of online orders placed before 1pm leave same day. Save more as you buy more - we offer up to 13 price breaks plus 3 spend-tier discounts. Read our customer reviews or get in touch if you need help picking the right furniture fastener.