PCB Substrates & Drill Materials
150 × 220 mm · FR4 1.55 mm · Single / Double-Sided · 18 / 35 µm copper · Drill underlay 2.5 mm
Product detailed description
FR4 copper-clad laminates and drill underlay sheets for mechanical PCB prototyping and in-house PCB fabrication.
MIPEC PCB Substrates & Drill Materials include FR4 copper-clad boards for circuit fabrication and dedicated drill underlay material for supporting through-drilling and contour-routing operations.
FR4 variants are available as single-sided or double-sided boards with different copper thicknesses, including lower-cost 2nd Quality versions for applications where minor cosmetic surface imperfections are acceptable.
FR4 Copper-Clad PCB Substrates
FR4 copper-clad laminate is the starting material for mechanically milled prototype PCBs. The copper layer is selectively removed during isolation milling while the FR4 laminate provides the mechanical base of the circuit board.
All FR4 variants in this product group have a thickness of 1.55 mm and dimensions of 150 × 220 mm.
Single-Sided or Double-Sided?
Single-sided material has copper on one side of the FR4 core. Double-sided material has copper on both sides and is used when conductive features are required on both PCB surfaces.
Available FR4 Variants
| Double-Sided FR4 | 18 µm copper · 150 × 220 mm · 1.55 mm substrate thickness |
|---|---|
| Double-Sided FR4 | 35 µm copper · 150 × 220 mm · 1.55 mm substrate thickness |
| Double-Sided FR4 – 2nd Quality | 35 µm copper · 150 × 220 mm · 1.55 mm substrate thickness |
| Single-Sided FR4 | 35 µm copper · 150 × 220 mm · 1.55 mm substrate thickness |
| Single-Sided FR4 – 2nd Quality | 35 µm copper · 150 × 220 mm · 1.55 mm substrate thickness |
18 µm or 35 µm Copper?
Copper thickness determines how much copper is present on the laminate surface before machining.
The available material range includes both 18 µm and 35 µm copper on selected double-sided FR4 variants, while the single-sided boards are available with 35 µm copper.
The required copper thickness should be selected according to the electrical and mechanical requirements of the PCB design.
Copper Thickness Is Part of the PCB Design
Copper thickness affects the conductive layer itself and should be chosen according to the requirements of the circuit rather than treated only as a machining parameter.
What Does 2nd Quality Mean?
2nd Quality FR4 boards are fully usable PCB laminate offered at a significantly lower price than top-grade boards, but the copper surface may contain minor cosmetic imperfections.
These may include fingerprints, scratches or light surface oxidation. Such imperfections make the material less suitable where a perfect cosmetic surface is required, but can make 2nd Quality material a practical choice for development, testing, education and many prototype applications.
Same Function, Lower Cosmetic Grade
2nd Quality refers to the surface appearance of the material. Minor fingerprints, scratches or light oxidation may be present, which is why these boards are offered at a substantially better price.
Drill Underlay Material
The drill underlay sheet is not a PCB substrate. It is placed underneath the PCB during operations where the cutting tool passes completely through the board.
This provides supporting material beneath the PCB for drilling and contour-routing operations and allows the tool to continue below the PCB surface without immediately contacting the machine table.
The underlay sheet has dimensions of 150 × 220 mm and a thickness of 2.5 mm.
Use Underlay for Through-Material Operations
Microdrills and contour routers are designed to pass through the complete PCB thickness. A drill underlay sheet provides the supporting layer underneath the board during these operations.
PCB Substrate or Drill Underlay?
FR4 Copper-Clad Board
This is the actual PCB material. Copper tracks and pads are created by machining the copper-clad laminate.
Thickness: 1.55 mm
Drill Underlay Sheet
This is a supporting consumable placed underneath the PCB during through-drilling and routing.
Thickness: 2.5 mm
Typical Applications
Technical Specifications
| Product group | PCB substrates and drill support materials |
|---|---|
| Sheet dimensions | 150 × 220 mm |
| FR4 thickness | 1.55 mm |
| FR4 construction | Single-sided or double-sided copper clad |
| Available copper thickness | 18 µm / 35 µm depending on variant |
| 2nd Quality variants | 35 µm copper; minor cosmetic surface imperfections such as fingerprints, scratches or light oxidation may be present |
| Drill underlay thickness | 2.5 mm |
| Drill underlay application | Supporting layer for through-drilling and contour-routing operations |
Part of PCB Milling & Drilling
FR4 copper-clad material provides the starting substrate for mechanical PCB fabrication, while drill underlay supports the through-material machining stages.
Need Milling & Drilling Tools?
Isolation cutters, flat endmills, microdrills and contour routers are available separately or as pre-selected PCB Toolsets.