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35mm Forstner bit for a concealed cabinet hinge

Updated: 23 October 2026

The hinge packet is on the door, the door is about 18 mm thick, and the bit you nearly ordered is labelled 1-3/8 in. A 35mm Forstner bit is the usual UK cutter for a concealed cabinet-hinge cup, and only when the sheet in that packet agrees. Depth, edge distance and a test fit matter more than a star rating. The twelve listings are on the [Forstner bit comparison](/hub/drilling-and-accessories/forstner-bit). The Products Compared editorial team wrote this on 20 October 2026 from those listings and UK fitting notes, not from a workshop trial. A qualifying purchase can earn a commission at no extra cost to you.

The hinge packet is on the door, the door is about 18 mm thick, and the bit you nearly ordered is labelled 1-3/8 in.

Our top picks

Aohoo Aohoo 16-piece Forstner set

Best overall

Aohoo Aohoo 16-piece Forstner set
8.3/10about £15.89
View offer
flintronic flintronic 6-piece Forstner set

Alternative

flintronic flintronic 6-piece Forstner set
8.2/10about £12.39
View offer
DTGN DTGN 35 mm Forstner bit, two-pack

Alternative

DTGN DTGN 35 mm Forstner bit, two-pack
5.6/10about £17.89
View offer
On this page
  1. 1.Confirm the cup is 35 mm
  2. 2.Depth and edge distance
  3. 3.Which bits in this comparison state 35 mm
  4. 4.Thin doors and chipboard

Confirm the cup is 35 mm

Read the hinge sheet before the bit advert. Many European concealed hinges use a 35 mm cup. Some compact hinges use a smaller cup, around 26 mm, and a 35 mm bore will not shrink to fit them. IRWIN's largest bit is stated as 1-3/8 in, converted as 34.9 mm. 34.9 mm is not printed as 35 mm. A cup specified at 35 mm ± 0.2 mm, as on one UK door supplier's sheet, is not an invitation to treat 34.9 mm as the same tool. Two UK guides put the centre about 22 mm to 22.5 mm from the side and about 100 mm from the ends. Probox prints 22.5 mm and 100 mm for its own doors, and your hinge sheet still wins if it differs.

Depth and edge distance

Depth is where the face gets broken. DIY Doctor uses a 35 mm bit and about 11 mm to 12 mm, then says to stop and test the cup rather than keep drilling on a thin door. Kitchen Warehouse describes about 10 mm to 12.5 mm deep. Probox's own doors are bored 13.5 mm ± 0.5 mm. Set a stop at the shallow end of what your sheet allows, bore a scrap of the same board, and press the cup in. On a door around 18 mm, a 13.5 mm hole leaves only a few millimetres of skin. If the cup is proud, go a small step deeper and test again.
Aohoo Aohoo 16-piece Forstner set

Testsieger

Aohoo Aohoo 16-piece Forstner set
8.3/10about £15.89
View offer

Which bits in this comparison state 35 mm

flintronic's six-piece set, £12.39, includes 35 mm. UK texts say that bit is hard to control in 18 mm plywood with a hand drill. Aohoo's sixteen-piece set, £15.89, stops at 35 mm, with alloy steel in the table and titanium language in the title. Hinrichs, the hsawbit seven-piece, Yueqing Zhongji and Nisorpa also print 35 mm. DTGN's two-pack is two 35 mm tungsten-carbide bits at £17.89. The warm tip says to use a drill press over 35 mm, so this size sits on that line. None of these rows is a Blum MINIPRESS cutter. Repeated doors belong on the drill press page.

Thin doors and chipboard

An 18 mm door is thin next to a 12 mm or 13.5 mm cup, and melamine chips if the rim lifts the coating. Faithfull's 35 mm tungsten-carbide bit is £27.61 including VAT, for a stand-mounted drill, and DeWalt's DT4543-QZ is a 35 mm TCT hinge bit. Neither is in this comparison. The cup has to stay a stopped hole. Practise on an offcut. Call a joiner when the job is a whole kitchen and you have no depth stop. Wider material checks are on the Forstner bit buying guide.

Common questions

What size Forstner bit fits a concealed cabinet hinge?
Usually 35 mm, if the sheet says 35 mm. Compact hinges can be nearer 26 mm, and a 35 mm hole will not do. IRWIN's largest bit here is stated as 34.9 mm, so it is not the labelled 35 mm cutter. Confirm the cup, buy the printed diameter, and test it in a scrap before the door.
How deep do I drill the cup?
Use the hinge sheet. UK guides sit in a range: DIY Doctor about 11–12 mm, Kitchen Warehouse about 10–12.5 mm, and one supplier's doors at 13.5 mm ± 0.5 mm. None of those is a law for every brand. Stop at the shallow end, press the cup in, and deepen only if it sits proud. On an 18 mm door, extra depth is how the face breaks.
Is 1-3/8 in close enough?
The IRWIN listing states that size as 34.9 mm. It is close to 35 mm and it is not the same label. If the packet's tolerance still grips the cup, a scrap will show it. If the cup is loose, or specified at 35 mm ± 0.2 mm, buy a bit that is stated as 35 mm.
Can I do this with a hand drill?
You can start a single cup if the bit stays square and you obey a depth mark. flintronic reviewers found the 35 mm bit hard to control in 18 mm plywood by hand. DTGN's tip points diameters over 35 mm to a drill press, and a 35 mm hinge bit is on that edge. For repeated doors, use a pillar drill.
Do I need a carbide hinge bit for MDF or melamine?
You need an edge that cuts the coating without lifting it, and a carbide-tipped 35 mm hinge bit is what Faithfull and DeWalt sell for that. A cheap set can cut a first plywood hole and still tear melamine. Faithfull also wants a stand-mounted drill. If one scrap looks clean, the set may be enough. If the coating is chipping, change the bit before the next door.

Related pages

How to use a Forstner bit

Forstner bit

Best Forstner bit for a UK hinge cup or metric set

Forstner bit set: check the diameter and the shank

Forstner bit on a drill press or in the hand drill

Sources

Public UK sources from the research digest, last checked on 20 October 2026. Shelf prices and star lines are the amazon.co.uk figures on the listings.

  1. HSE: wood dust (retrieved 20 October 2026)
  2. PPE at Work Regulations 1992 (retrieved 20 October 2026)
  3. HSE: PUWER overview (retrieved 20 October 2026)
  4. Bosch Professional GB: Forstner bits (retrieved 20 October 2026)
  5. Faithfull: TC 35 mm hinge boring bit (retrieved 20 October 2026)
  6. DIY Doctor: fit a concealed hinge (retrieved 20 October 2026)
  7. Axminster: 16-piece Forstner bit set (retrieved 20 October 2026)
  8. UK Workshop: Forstner bits in hand drills (retrieved 20 October 2026)