Funtek Engineering Manual
Sintered Stone Fabrication & Installation Manual
Working limits for corner radii, cutout clearances, overhangs, support, joints, undermount sinks, cutting, handling, and installation across Funtek slab thicknesses.
- Minimum internal corner radii from R5 to R10 by thickness
- Cutout-to-edge ≥70 mm; preferred ≥100 mm
- 12 mm overhang 100 mm without reinforcement; 150 mm with reinforcement
01 / THICKNESS & APPLICATION
Select Thickness After Support, Cutouts, Edge Design, and Finished-Part Size Are Known
Thickness alone does not make a worktop safe. Cabinet level, continuous bearing, opening geometry, transport route, sink support, seam position, and the fabricator’s cutting process must be reviewed as one system.
| Thickness | Normal Funtek production | Recommended uses | Required support | Minimum inside radius |
|---|---|---|---|---|
| 6 mm | Standard | Wall cladding, furniture skins, cabinet faces, decorative panels | Full and continuous backing; do not treat as a self-supporting countertop | R5 mm |
| 9 mm | Standard | Bathrooms, wall panels, light-duty horizontal surfaces | Continuous support, particularly around openings and free edges | R5 mm |
| 12 mm | Standard / preferred worktop | Kitchen worktops, islands, dining tops, commercial counters | Level cabinet frame plus transverse support at 400–500 mm recommended | R8 mm; R10 preferred |
| 15 mm | Standard | Premium worktops, large islands, furniture requiring greater rigidity | Level cabinet frame plus transverse support at 500–600 mm recommended | R10 mm |
| 20 mm | Custom production | Heavy visual edge, premium counters, selected structural layouts | Support plan remains mandatory; confirm format, quantity, finish, and lead time | R10 mm minimum |
02 / OPENINGS & CORNERS
Cutout Geometry: The Three Distances That Prevent Most Countertop Cracks
Sharp 90° internal corners are not accepted. All sink, hob, tap, socket, and service openings must be shown on the latest drawing before material reservation and cutting.
Opening to finished slab edge
70 mm minimum; 100 mm preferred. Use 100 mm where the opening is large, the edge carries a sink, a seam is nearby, or transport stress is high.
Between two adjacent openings
120 mm minimum; 150 mm preferred. Do not leave a narrow bridge between a sink, hob, tap hole, socket, or service penetration.
Machine-drilled radius, never a sharp notch
R10 mm recommended for countertops. Drill or waterjet the corner first, connect the straight cuts to the radius, and finish without overcutting.
Cutting sequence
03 / SUPPORT & OVERHANG
Unsupported Projection Is Limited by Thickness; Sink and Appliance Loads Need Their Own Support
The values below apply to uniformly supported, level cabinetry and normal residential loading. Concentrated loads, commercial use, waterfall ends, mitred aprons, transportation joints, and unusually long spans require a dedicated frame plan.
| Condition | Without added reinforcement | With steel / aluminium reinforcement | Required action |
|---|---|---|---|
| 12 mm overhang | Up to 100 mm | Up to 150 mm | Larger projections need a bracket, steel subframe, or reinforced cabinet. |
| 15 mm overhang | Up to 150 mm | Up to 200 mm | Check edge build-up, seated load, joint position, and transport route. |
| 12 mm transverse support | Maximum 600 mm; 400–500 mm recommended | Add support at seams, cutouts, appliance voids, and dishwasher openings. | |
| 15 mm transverse support | Maximum 800 mm; 500–600 mm recommended | Commercial counters use ≤600 mm unless separately engineered. | |
| Undermount sink | Independent mechanical cradle or rail support required | Do not hang the sink, water, waste disposer, or service loads from adhesive and slab alone. | |
04 / JOINTS & INSTALLATION
Build Movement and Installation Tolerance Into the Finished Surface
2–3 mm recommended
Use a minimum 2 mm joint between finished parts. Keep seams away from opening corners and support both sides of the joint.
3–5 mm at walls and fixed elements
Do not wedge a slab tightly between walls, columns, cabinet towers, or other fixed construction. Cover the relief with the specified flexible sealant or trim.
No local high points or unsupported voids
Level cabinets first. Shim continuously where required; do not force the slab flat by clamping it to an uneven base.
05 / ENGINEERING REVIEW CASE
12 mm Matte Marble Look Kitchen: Three Drawing Changes Before Cutting
The project combined a large undermount sink with a visible marble vein direction. The first drawing left too little material at the front rail and treated the sink as an adhesive-mounted component.
opening-to-edge distance after factory review; cutting completed without cracking and the approved vein direction was maintained.
Changes made before production
The cutting sequence was changed to drill the radii first, connect straight cuts with reduced feed near the corners, finish the opening, and recheck the part before packing.
FUNTEK TECHNICAL LIBRARY
Use the Four Documents as One Project-Control System
The product data sheet defines what is supplied; the face guide defines what is seen; the fabrication manual defines how it is processed and supported; the quality standard defines how it is accepted.
Fabrication & Installation
Radii, cutouts, overhang, support, joints, sinks, and cutting sequence.
02Technical Data Sheet
Body groups, formats, thicknesses, finishes, tests, and slab weights.
03Face & Bookmatch Guide
A/B faces, direction, sequence, layouts, labels, and spare planning.
04Quality & Inspection
Dimensional tolerance, surface checks, batch, shade, packing, and claims.
Send the latest drawing, not only a colour reference.
Include application, product, body type, finish, format, thickness, quantity, face requirement, processing, destination, and project schedule. Funtek will return the material route and factory review points with the quotation.