20mm x 3mm N42 Neodymium Disc Magnets
1
$4.16
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$4.16
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Hobby Heaven
20mm x 3mm N42 Neodymium Disc Magnets
$4.16
Sale price
$4.16
Regular price
Shipping calculated at checkout.
Number of packs
In stock · same-day dispatch before 3pm
- Store rating 4.9/5 · 2141 reviews
- UK tracked delivery
DWG · Product Information
PROJ: MAG/D20X3/1 · SHEET 2 / 4
Notes · Q & A
Which magnet size should I choose for miniatures?
A 2×1 mm disc suits infantry weapon swaps, while 3×1 mm is a practical step up for arms and small components. Sizes around 3×2 to 5×2 mm work well for basing and larger parts, with 5×3 mm and above better suited to vehicles, large models and army transport. Each listing includes a calculated pull figure in grams so you can compare sizes on the same basis.
What does the N42 magnet grade mean?
The grade describes the magnetic material: at identical dimensions, a higher number generally produces more pull. N52 is typically around 20–25% stronger than N42 at the same size, but increasing the magnet's diameter or thickness usually makes a larger practical difference than changing grade alone. Our range is clearly specified as N42.
How do I keep the polarity consistent?
Before separating the stack, mark one face with a permanent marker and use that mark as your polarity reference. Dry-fit every pair before applying adhesive, and glue the two halves while the magnets are still attracting each other in the intended orientation. Reversing one magnet is one of the most common magnetisation mistakes.
What size hole should I drill for a magnet?
Use a drill matching the magnet diameter; for a designed 3D-printed socket, allow roughly 0.1 mm extra diameter. Make the recess approximately the magnet thickness plus 0.2 mm for adhesive so the face can sit level with the surrounding surface. CA adhesive is suitable for fixing these magnets into plastic, resin or metal parts.
How should neodymium magnets be handled safely?
Swallowing two or more magnets can cause serious internal injury, so keep loose magnets away from children and use them only for adult hobby work. Neodymium magnets are also brittle and may chip if allowed to snap together. Bring them together slowly from the edge rather than letting their flat faces strike each other.
Notes · Logistics
Shipping
Orders placed before 3pm (Mon–Fri) are dispatched the same day. UK delivery is by Royal Mail 24 Tracked. Free UK delivery on orders over £70. International delivery available via Royal Mail International Tracked or courier.
Returns
If you're not happy with your purchase, contact us within 30 days for a full refund or exchange. Items must be unused and in original packaging.
Table · Specification
Technical specifications
Product details
Brand
Hobby Heaven
Product code
MAG/D20X3/1
Type
Accessories
Made in
China
Dimensions & contents
Diameter
20 mm
Thickness
3 mm
Weight per magnet
7.16 g
Magnetic properties
Grade
N42
Pull to steel (calculated, zero gap)
4300 g
Pull to steel
42.17 N
Magnet-to-magnet pull
4300 g
Shear resistance (estimate)
640 g
Magnetisation
Axial
Max working temperature
80 °C
Coating
Nickel-Copper-Nickel (NiCuNi)
Usage & compatibility
Drill bit
20 mm
Hole in 3D prints
20.1 mm
Recess depth
3.2 mm
Size comparison
20 mm — almost exactly a 1p coin (20.3 mm)
Related sizes
Also consider
Product
20mm x 3mm N42 Neodymium Disc Magnets
Code (proj)
MAG/D20X3/1
Brand
Hobby Heaven
Hobby Heaven · By hobbyists, for hobbyists
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