Helsinki Model Expo 2007 - Day 2

A long day at Model Expo today...

Our main new attraction for this year was Micro Magic sailing in the pool - and it worked great!

This picture shows a general view of the pool, the marks, and the blowers(the yellow and blue fans at the top of the picture) that created wind for us. The size of the pool was 14x17m and we sailed a windward-leeward course along the diagonal of the pool.

Here the boats are rounding the leeward marks.

Rounding the top mark, with one of the fans in the foreground.

Looking for the stream of quickly moving air on the run.

What can be done better next year? Now we have three boats, but there's certainly room for more. Perhaps up to 6-8 MicroMagics could be sailing at the same time. I'm sure that would please the crowd as there will then always be something to watch and incidents all the time. One or two more fans would not hurt either. The power of the fans was fairly OK with a nice gust towards the top of the course and steady decreasing wind towards the leeward marks. Finally, frequency allocation between us, the motor boats, the car track, and robo-war was a bit of a hassle - bring only 2.4 GHz radios next time!

A general trend across all disciplines in model hobby(cars, boats, airplanes, etc.) seems to be towards smaller, lighter, and cheaper models. New tiny electronics makes it possible to build these models. Here's a plane with a small LiPo cell in the front (I'm told these cells can come from bluetooth headsets or similar), a combined receiver/motor controller in the middle, and two motors in each wing for propulsion/control (people use motors from CD-players, cell-phone vibration alarms etc)

Even the smallest mini servos are too heavy for the lightest models, so people use these more or less home-made coil/magnet actuators. There are two magnets, one on the moving control surface, and one on the stationary part. The stationary magnet attracts the moving magnet and thus centers the control surface. When a current is applied to the coil the control surface can be deflected each way. Weight 0.3g . Brilliant!

More and more devices are showing up on 2.4 GHz. This is a ready-to-fly plane and transmitter from the Kyosho stand. With the electronics becoming cheaper and cheaper all the time I'm sure these things will show up in supermarkets for about 50 eur or so.

There were many heli/airplane simulators hooked up to a computer and a wall-projector. Great fun, and no expensive re-building after each crash. I might actually get one...

Another futuristic looking transmitter from the Kyosho stand. (is it for a simulator?)

One company was showing tiny cnc-lathes and mills. These were from some uknown Asian company. Looks like they are entry-level hobby-cnc stuff: small stepper motors connected to normal threaded screws.

These machines are kind of cute, and may be suitable for making a small number of very small parts in soft materials. I'm afraid that Jari's and my own cnc-hobby (or is it an addiction? 🙂 ) will require something substantially bigger and more expensive for our next machine (think Haas Minimill or similar...)

A nice long-exposure shot of one of many slotcar tracks.

I'm hoping to shoot some sailing videos tomorrow.

Preparing for Model-Expo

I spent most of the afternoon and evening preparing the Finnish RadioSailors stand at the Helsinki Model Expo which will be open Friday - Sunday. The plan is to have 2 IOMs, one 5.5mrc, and about three MicroMagics on display. A 32" LCD screen displays sailing videos while people interested in the sport can pick up an information leaflet or ask questions from our club members who will be manning the stand. New for this year is MicroMagic sailing in the pool (which is 22cm deep I am told) on Saturday and Sunday. Timo and his team from Tampere are bringing three MicroMagics while I fixed the wind: two powerful blowers leased from cramo (the two black dots in the far corner of the pool below). A quick test run showed that two blowers of this size were quite well suited for the 14x17 m pool. When blowing diagonally across the water all but the extreme corners were covered with wind, and even at the far end we had at least 2 m/s. Ofcourse the wind speed distribution is a bit uneven with the speed going significantly up close to the fans, but you can't have it all...

Noux building in Norway


Steinar from Norway sent me some more pictures of his Noux boats. He has completed the first boat (see below), and is now building a second one.


Another view of the spray-painting setup.


The bulb is home-made, cast in a plaster mould.


Here is Steinar's first boat, now completed and painted. I posted some building pictures earlier here and here.

Steinar asked if there is a Noux-logo. Sure! I just need to post it online in some common format. Stand by...