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GMTRCPLY - GeoMeTRiCPLaY - Magnetic Sticks

 Introduction   ·   Desktop Sets   ·   Floor Play   ·   Steel Balls   ·   Instagram Posts 

Magnetic Sticks
Different Magnetic Sticks 

Introduction

The classic Magnetic Stick sets come with plastic coated magnetic sticks, and ferromagnetic spheres. Other terms are Rods and Spheres, or Bars and Balls.

Usually, the ends of each stick have opposite magnetic polarity. But there are also sets where the ends have the same magnetic polarity, and therefore contain two types of sticks.

Desktop Size

Current "regular" sets come with short (~27mm) or long (~58-60mm) sticks. The balls have 12.0-12.8mm diameter.

The photo shows different Magnetic Sticks, from left to right...

The table below shows the characteristics for some sets.
Brand Type Stick
Length
Diameter Weight Magnetic Strngth Ball
Diameter
Weight Notes
Generic Short 27.1mm 6.7mm 3.9g medium 12.0mm 7.2g
Generic Long 58.0mm 7.0mm 6.8g medium 12.0mm 7.2g
BANBBY Long 58.0mm 7.0mm 6.7g medium 12.0mm 7.2g
Goobi Long 59.9mm 9.9mm 4.1g high 12.8mm 8.5g
Geomag Long 58.2mm 7.6mm 9.7g high 12.8mm 8.5g
Geomag PRO-L 58.2mm 7.4mm 9.8g high 12.8mm 8.5g
Geomag Original 27.0mm 7.4mm 4.6g high 12.7mm 8.4g Out of production
Wisemag Short 30.9mm 6.4mm 5.7g very high 12.7mm tbd Out of production
Magnetic World Medium 39.6mm 8.9mm 1.4g very low 12.0mm 6.9g Junk, for reference purposes

For more information, see:   Stick Sets 

Floor Play

There are many different sets that are usually intended for toddlers. Because of the large size, the sets come with hollow tin balls of 30-60mm diameter. But the sticks can also be used with steel balls of appropriate size. When using solid steel balls, the magnetic attraction is stronger, but the weight of the balls increases by the power of three with the radius.

The market is flooded with cheap Chinese sets, but there are also high quality products. However, with increasing magnetic strength, there is also the danger of pinched skin.

Brand Long Medium Short Ball
Diameter
Notes
Goobi Juniors, old size 144mm 60mm Bipolar sticks; min. sphere diameter ~56mm
Goobi Juniors, new size 130mm 53mm Bipolar sticks; min. sphere diameter ~45mm
Nexus Magne Sticks 81mm 60mm 54mm Bipolar sticks; min. sphere diameter ~46mm
SmartMax 119mm 71mm 45mm Monopolar sticks (indicated by warm/cold color); min. sphere diameter for long ~42mm, for medium ~36mm
Magformers Stick-O 115mm 68mm 45mm Rotating internal magnets; min. sphere diameter ~45mm
Generic Chinese 87mm 52mm 35mm Bipolar sticks; different detail design

For more information, see:   Stick Sets 

Steel Balls

You can combine any ferromagnetic sphere with the magnetic sticks. Below are some examples for 100Cr6 (1.3505) industrial grade steel balls that I have available.

Diameter Volume Weight Density
9.00mm0.38cm³2.98g7.80
9.53mm0.45cm³3.54g7.82
10.00mm0.52cm³4.09g7.81
10.50mm0.61cm³4.74g7.83
11.00mm0.70cm³5.45g7.81
11.50mm0.80cm³6.22g7.81
13.00mm1.15cm³8.99g7.81
14.00mm1.44cm³11.22g7.81
15.00mm1.77cm³13.81g7.81
16.00mm2.14cm³16.73g7.80
17.00mm2.57cm³20.07g7.80
18.00mm3.05cm³23.84g7.81
19.05mm3.62cm³28.21g7.79
20.00mm4.19cm³32.68g7.80
21.00mm4.85cm³37.86g7.81
22.00mm5.58cm³43.47g7.80
25.40mm8.58cm³66.99g7.81
28.00mm11.49cm³89.73g7.81
30.00mm14.14cm³110.34g7.81
32.00mm17.16cm³134.04g7.81
35.00mm22.45cm³175.18g7.80
40.00mm33.51cm³261.57g7.81
45.00mm47.71cm³372.50g7.81
50.00mm65.45cm³511.00g7.81

If you want to calculate the weight for a certain diameter, you can assume a density of about 7.8.

GMTRCPLY Posts on Instagram

For a start, these are the links to the Instagram Posts by topic.

Magnetic Sticks

 » Introducing Magnetic Sticks 

 » Platonic Solids with Face Pyramids 

 » Icosahedral Star with short and long Magnetic Sticks 

 » Icosahedral Star with short and long Magnetic Sticks, Take 2 

 » Dodecahedron from Magnetic Sticks 

 » Cuboctahedron from Magnetic Sticks 

 » From Cuboctahedron to Octahedron 

 » Truncated Tetrahedron from Magnetic Sticks 

 » Truncated Octahedron from Magnetic Sticks 

 » Snub Cube from Magnetic Sticks 

 » A Pair of Snub Cubes with long sticks 

 » A Pair of Snub Cubes with short sticks 

 » Rhombicuboctahedron from Magnetic Sticks 

 » Icosidodecahedron from Magnetic Sticks 

 » Icosidodecahedron in Colors 

 » Megaminx Twisty Puzzle inside an Icosehedron 

 » Long Sticks, Small Balls - Short Sticks, Large Balls 

 » Gyroelongated Pentagonal Birotunda 

 » Triangular Torus - 3×4 Toroidal Polyhedron, Order 3 

 » Triangular Tori - 3×4 Toroidal Polyhedrons, Orders 1-4 

 » Square Torus - 4×4 Toroidal Polyhedron 

 » Pentagonal Torus - 5×4 Toroidal Polyhedron 

Giant Magnetic Sticks

 » Icosahedron with Goobi Juniors 

 » Icosahedron with Nexus Magne Sticks 

 » Cuboctahedron with Goobi Juniors 

 » Stellated Octahedron "Stella Octangula"  with Goobi Juniors

 » Truncated Tetrahedron with Goobi Juniors 

 » Snub Cube with Goobi Juniors 

Geometric Dissections with Magnetic Sticks

 » Tetrahedron Dissection with Trido 

 » Octahedron Dissection with Trido 

 » Rhombic Dodecahedron Dissection with Creatice Whack Rhombi 

Magnetic Sticks and Creative Whack

 » Short Extended X-Ball 

 » Short Extended Y-Ball 

 » Short Extended Star Ball 

 » Short Extended Rhombi 

 » Short Extended Ball of Whacks 

 » Short Extended Eureka Ball 

 » Star Ball and Steel Balls 

 » Long Extended X-Ball 

 » Long Extended Y-Ball 

 » Failed Long Extended Star Ball 

 » Star Ball: Long Extended Rhombic Icosahedron 

Steel Balls and GeoBender

 » Hexagonal Tower with Steel Balls as Spacers

 » Hexagonal Castle: 16 GeoBender and 66 Steel Balls

 » Rack of Ten: 20 GeoBender and 60 Steel Balls

 » Pagoda of Hexagons: 18 GeoBender and 54 Steel Balls


Hans-Jürgen Reggel   ·   http://www.hjreggel.net/gmtrcply/   ·   Imprint   ·   2024-04-28 ~ 2024-10-03