The Speed sagaI don’t remember when the first “Speed” motors appeared – probably the mid 1990s. Basically Graupner observed the chaotic motor naming and supply scene, and decided to make it simpler and better, and they did!
They introduced a range of propulsion motors which covered most of the perceived requirements (at that time). I believe that the aim was electric flight; and this spins off into fast electric boats (rather similar requirements),.
Inflation strikes!The first sizes introduced were the 380 and 550 sizes, and these were christened Speed 400 and speed 600 respectively. They were well made, they all sported built in capacitors(between the terminals) and they all had internal brushgear and metal end-bells.
I still don’t know if Graupner picked existing motors from the manufacturers range or had them made specially in sufficient quantities (when Derek Knight ordered the KP01 motor he had to purchase 10,000 at a time). I lean towards the first view since some of the Speed motors that followed are distinctly weird, and not what a logical German commercial organisation might have defined!
It is a characteristic of the Speed 400s (and some of the other sizes) that they have a number attached to them (e.g 6V, 7.2V). It is permissible to take this as a normal operating voltage, and you won’t go wrong in doing so.
In fact it is a signal rather like the “winds” which indicates the size of the wire and number of turns – for example the S400 4.8V is a serious ratmotor with 3 turns of fence wire and is capable of devouring its brushgear if loaded too highly. The S400 7.2 V is a mild motor wound with finer wire and will tolerate overloading and slow operation more calmly. But many people run a S400 4.8V at 7 volts through a big ratio gearbox which allows it to spin fast with reasonable load . I run a S400 6V on 10 nicd cells (12V nominal) in a ducted fan and it still works after 20 runs or so.
1. So the sequence of events goes like this:
2. Graupner introduce the speed motors
3. People try and fry and publish “what works” tables ()
4. Graupner introduce variants, more sizes
5. People try them and fry them and publish “what works” tables (
6. goto 4
The variants now include “Eco”, “Race”, “BB” and “Torque” and frame sizes from 280 (parkflyers) to 900 with a lot of fill-in sizes as well (
http://homepage.ntlworld.com/edward.matthews/ddmbc_files/motors/graupner.htm). The initial range were all ferrite motors, and competitively priced, but now the range includes Neodymium versions – with rare-earth magnets.
The Voltage descriptions are still just a recommendation for normal voltage if used as Graupner intended. If you run a “7.2V” S600 direct drive on a tug propeller on 7.2 V you will become quickly familiar with SpeedSmoke. It might work well on 3.6V in this application!
Speed Summaryhttp://www.alansmodels.com/main_site/engines/motor_graupner.htmThis list gives the shaft sizes, etc - this needs a little careful reading since similar motors can have different fixing sizes and shaft sizes
Intended for electric flight, and for high revs in carefully controlled loadings, so translating into boats takes some care. All of them (I believe) are 3-pole motors; some of them have staggeringly high Kvs (speed 300 especially, and I would suspect, the Race versions)
Use them for high speed boats, geared boats and air boats
Don't let them slow down and slog
Start with little props; work up in size till the motor glows then go back 2 sizes
Odds and SodsWhile rambling down memory lane a couple of possibly relevant points come to mind:
1) YOU can rewind ANY motor to suit ANY voltage and load. Fact, quite easy - you have to be able to solder and count to about 30
2) Americans (and others) started christening electric motors by the glow Motors (in Cubic inches) they were supposed to be able to replace - so the 540 size is still refereed to as the "05" class in the US. Astro flight still label their brushed range this way - and they don't lie.
3) There has been intense discussion about direction of rotation and timing of all the Speed motors - and it applies to all electric motors as well.
The best have variable timing - ALL can be adjusted to suit the application.
I THINK that the Speed range come neutrally timed - this means that they are incorrectly timed for either direction of rotation and any load and speed! There has been much published on adjusting the timing - a typical spiel is attached.
http://www.ef-uk.net/data/speed600race.htmI go now to get an ice pack and research what Martin's alphabet of letters means!
Comments, additions, refutations welcomed
andrew