I have some more building galleries/instructions thanks to Joo G.

Some building ideas/instructions for Supermag and Geomag: 1 (non-English), 2 (non-English), 3 (very nice! includes description of magnetic forces), 4 (annoying javascript) (non-English), 5 (non-English), 6 (non-English), 7 (non-English, WMV-format videos), 8 (describes magnetic forces)

Nelson M. and Joo G. both point me to Geomag SA, the Geomag site. Apparently the inventor of Geomag and the previous producer of Geomag, Plastwood, no longer get along. Plastwood has abandoned Geomag and come out with their lookalike, Supermag. This would explain the promotional material I've read, in which Plastwood makes it sound like Supermag is the successor to Geomag. It also explains the difficulty of finding Geomags―I'm sure Geomag was scrambling to find a new manufacturer. The catalog includes a list of their sets, including some building image galleries. The Geomag site argues that Geomag is better than Supermag:

  1. Supermag magnets are ~25% weaker
  2. Supermag magnets are a single bar instead of Geomag, which has two bars (!)

They also describe why they think two different lengths is a dumb idea. The example they give is essentially suppose you want to build something with only one length... you have to buy all these extra magnets that you don't use. True, but with the new Geomag you end up having to buy these "panels" (at least it appeared that the panels were included in sets with rods). I do like having a single length but I can also see some advantages of having two lengths. Their site navigation is a little confusing, but eventually you'll find a gem: Geomag: Come & Play. This part of the site has beautiful diagrams showing how Geomag works, how you should build things, and so on. In particular, they show the two-magnet interior of a Geomag rod. From what I read on their site, Supermag contains a single magnet in each rod. However, it's not clear to me what the difference is in practice. Geomag claims between the magnets is a steel rod. Doesn't this essentially turn it into a single magnet? In any case, the Geomag site is convincing. It matches my own experience with Geomag vs. Supermag: Geomag is generally better than Supermag but Supermag is still decent.



Ethan wrote at Wednesday, November 4, 2009 at 9:07:00 AM PST

Do you have any more info on geomag vs. supermag and plastwood? this was very interesting, I used to buy cases of geomag a bunch of years ago. I am thinking about getting more, and this was very useful information. (I tried doing a search of your blog for geomag, but nothing came up, not sure what I was doing wrong. Have your written any more on the subject?)
Thanks a bunch,

Amit wrote at Wednesday, November 4, 2009 at 9:19:00 AM PST

Hi Ethan,

Sorry, I haven't written anything recent. Back in 2004 I bought the Supermag (see http://amitp.blogspot.com/2003/12/shopping-for-myself-this-christmas.html and http://amitp.blogspot.com/2004/01/geomag-vs-supermag.html and http://amitp.blogspot.com/2003/12/playing-with-magnets.html) and found some sites with building ideas (see http://amitp.blogspot.com/2004/09/geomag-pictures.html and http://amitp.blogspot.com/2004/01/geomagsupermag-galleries.html) but some of those links are broken now :(

I played with my Supermag set for a few months but then got bored of it, and now it sits in a box somewhere.