Servo size

Is it OK to use small size servos (micro and pico sizes)? The rules require 4 AA batteries and 2 servos, but do not appear to regulate the size of the servos. It appears that micro servos may suffice for the sail servo if a balanced rig is used, and a pico servo (as used on the smallest model airplanes) will suffice for the rudder servo. This would save about 1.5 oz (43 gm) altogether. An addition weight saving can be achieved with the new ghz radio receiver, if allowed.

I have not seen any mention of this issue, but it appears that most people are using standard size servos, which minimizes cost.

Any comments?

I would very much be in favour of everybody using standard size servos as well as 4 AA batteries. Otherwise there is a strong incentive to use smaller and more expensive servos, receivers and AAA or even smaller (hearing aid?) batteries, etc…
Instead of ingenuity, imagination, seamanship and persistence, we will end up using MONEY. Anyone interested in a $300 servo? It will weigh half a gram and pull 4 Kg Metres. (You don’t think it can happen?)
Rod
08 CAN Razor

i see your point rod, but i must admit, i def. use mini/micro servos. my stiletto for instance… i use a micro for the rudder, and a mini high-torque for the sail… the boat can’t fit anything bigger… as for my bearfoot’s i use standard sail - because i am just that cheap - but i use micro for the rudders, because i really like being able to save the weight… i think that while what you say is valid - we really DON’T want the footy class to become a shootout of who can by the most expencivo, best gear - but if one is looking to build a really cutting edge boat, i am not sure i see any choice but to go mirco/mini… weight is everything…:scared: [i should note that this is what i have found… i am sure that there are others who will have ready and good proof that i am off my rocker!:rolleyes:]

alright, i am done… back into my hole!:smiley: [that is where i have my secret footy labratory!]

over and out

B.

bluebirds are small, light, fast, AND cheap. no need to spend lots for good servos. (no i don’t work for bluebird, but man i’m impressed)

where can i find them? do they have a website?:slight_smile: [drools] i think i may have found the servos for my new proto!:stuck_out_tongue:

http://www.blue-bird-model.com/

i’m partial to the BMS-371 8g Micro Servo for rudder, and BMS-380MG 15g Micro Servo (Metal Gear) for sail.

Once we start being over-restrictive on electronics, we potentially end up in the ludicrous situation that the traction control that comes as standard in a Volvo (as a safety device) is illegal in Formula 1 Motor Racing. Electronics will get cheaper: restrict them now and your are just running next weeks
's dinosaur off the production line.

I would normally agree with everything that has been said about the need for micro servos, except that the rules already limit footy sailors to 4 AA size batteries,instead of the newest micro-mini cells which may need to be recharged every 10 minutes (I don’t think they’ve been invented yet, but wait a few months!). If one part (the heaviest!) is restricted, why not the other parts of the electronics?
Incidentally, I am attempting to make a non-conforming, moveable-weight sailing dinghy Footy, using 4 AAA batteries, in a Razor hull, but she presently lies on her side and is not yet self-righting.
Rod
08 Can Razor

You have such a way with words Angus!!! :stuck_out_tongue: :wink:

Not being a ‘footyer’ myself but being interested in them I have no authority on this, but here’s my view on this subject anyway! Ignore at will!

I think it comes down to the basic principles of the footy ethic and idea in the first place. If the aim was to create a class of elite and super high performance models, then naturally the smallest and lightest gear available and with a costs to match is going to help. Anyone wanting to get into footys will have to realise that they are entering an elite class and that if they want to have any chance of success they’ll have to remortage their house to pay for it (so to speak!) as is seen in many of the larger classes.

But if the aim was more like creating some tiny, fun, cheap, quick, simple, etc, etc, little models to play with and maybe race from time to time, then the cheaper and bulkier standard radio is a reasonable route to take with the rules. It certainly levels the financial end of the playing field a lot.

Or is the aim of the class to develop the ultra low reynold’s numbers end of hydrodynamics or rigs? In which case forget the radio and concentrate on developing the technical bits!

Anyway, that’s only my opinion, from a devoted Micro Magicer where such issues are avoided by ‘one designing’ everything from the start. And I’m not into racing anyway!

I’m with Nigel … micro-servos are available for what amounts to pennies … just bought a sub 10gm servo for 12 bucks … be silly not to put weight into ballast where it belongs … really they’re not out of reach and suit the platform far better than the portly pieces that are the alternative …

Unfortunately, rules cannot be interpreted on principles and ideas of what the class is “supposed” to be like. We grapple with that every day over here in the States as everyone and their brother tries to define what our “founding fathers” meant - or intended ! :mad:

Once the class goes down the road as a development class, whether 12 inches long, 36 inches, 48, 8 feet, 20 feet or 40 feet - development means just that - you are allowed to do anyhting NOT prohibited. Even one designs try this and find out folks can identify loopholes quicker than they can be plugged. I am not an ODOM racer, but discussion came up about having a smaller rig for stronger winds. The class rules (one design) allow only one rig. The rules prescribe the mainsail luff is 52" (as I recall) but nothing in the rule prevents a sailor from reefing his sail (not the stiff mylar ones of course - but soft rip-stop nylon is not mandated) to whatever sail area he wants so he can race in many wind conditions with optimum sail area. They will probably make a rules change in the future to catch that one, as the "intent’ was to have all boats identical as possible regarding rig/sail area.

To name a specific winch is hard - since the Laser Class specified a winch - but have had to change rules to allow the HiTech replacement winch now that the old model is no longer made. Anthor problem with "naming a product if you don’t control it’s manufacturer.

Basically, I am saying when you elect to enter a class that is developmental, it is suggested the rules be read and understood so you know what you are getting yourself into. In the case of the Footy, the basic idea was to create a boat at a specific length with few other considerations. As you can see, the original balsa slab side fFooty has given way to ultra-high tech carbon fiber built in a mould. Was this what the originators of the class wanted? Hard to tell - but it is where it headed when it was designated as development. So to play, one must pay.

Of course, if you do not race, it doesn’t matter - right?

just to let everyone know, i’m not all about super-duper high tech vessels.
(i’m not implying anything) did that first, because that’s where i have some given abilities.

i do plan on building a pintail, because of it’s beautiful clasic looks, i would like to be like most of the sailors here, and have an aray of boat styles to play with.

one of the ozzy clear hulls will be in my collection as well (in time).
going to do a wonder woman theme (never mind my linda carter lusts, that’s my business.) going to put some leds inside.

(also not implying that any others are low tech, it’s all diferent types of art to me)

Whats a standard servo? dumb question you might say or is it?
Next question…suppose the rule states that standard servos must be used.fair enough right?
So at an event you will present your boat to be mearsured…you will have to pull the servos out of your boat for mearsurment.Stupid you say? not at all.
How long to think it will take before someone builds a small servo into the case of a Standard one.Not long at all unless the rules state that they will be removed for mearsurment.
Whats more expensive now? a rule cheating standard servo or a cheap (and they are cheap now) micro servo?
Don’t think anyone will cheat?? think again.

When making rules one must be vey careful to ensure that the rules can actually be enforced.
Is everyone happy to have there servos pulled out before racing?

The battery rule was easy enough…since everyone normally has them removable so it is easily enforced,this rule keeps the total electronic package no matter what servos are used into a resonably small range weight wise.
The lightest possible setup is a shade under 100g…with standard servos and heavy batteries about 200g.A difference of only about 1/5 of a typical Footy’s displacment.

Still don’t like the rules?
2 choices,
get enough ppl behind your point of view and try to get the rule changed or
play in another class.
Fair enough??

Doug and Trevor - as usual, I agree BUT …

As I have found in my arrogance and to my cost, drafting yacht rules is VERY difficult. A logically tight result necessarily looks like an Act of Parliament - that’s what Acts of Parliament are all about - and is just as comprehensible as the 2nd Schedule to the Town and Country Planning Act (Amendment) Act 1986. Further, the highly trained, highly paid people, backed by big support budgets, who draft legislation frequently get it wrong.

I'm the Parliamentary draftsman and I write the country's laws;
Of half the litigation I'm undoubedly the cause. 

Here we are talking about well- meaning amateurs whose skiils and inclinations are more likely to turn to engineering than to the law. It is vitally important that the rule be interpreted with common sense and aviewof what it was trying to do. Although this is very alien to the Anglo-Saxon mind, it is perfectly possible to work in this way - it is how all of Scandinaviaworks- some 22 million of the world’s richest and most highly ‘developed’ people.

I must admit it doestake some getting used to. The first major Swedish legal translation I did was a shareholders’ agreement contingent on the merger of two very larger energy companies. In theUSit wouldhave come in a suitcase, in the UK in a couple of volmes, in Sweden 30-odd pages.

So farasI am concerned, the current echnical team were appuntedon the basisthat they probably have the atttitude to make good Swedish judges. At theendof he day, the chancers knowwhen they’re stretching mattersand can take their luck: Footys are cheap and the consequences of your wonder rule cheat being crippling are pretty minimal.

Today I noticed that there are some rule interpretations on this website, which I had failed to notice previously, entitled “Rule Interpretations prior to January 2007”. They specifically state that any servo is acceptable, with no restrictions. This is obviously an authoritative answer to my question. So I have unintentionally sent everyone off on an unnecessary philosophical exercise. Please accept my apologies.

Walt H.

No problem Walt - we love to exercise !

:zbeer:

To quote my Dad:
“There are four and twenty ways
Of constructing tribal lays,
And every single one of them
Is right”

The other side of the coin to this class isthat it was design to be simple enough to build that a kid ( like a Cub Scout) could build one, and since these kids aren’t working 8-5, their allowance will only let them get a cheapie radio system; the kind without micros or mini servos.

Rubbish, micro servos are in many cases less cost than so called “standard servos”
Check it out!
http://www.hobby-lobby.com/servos.htm

Maybe you will go out of the way to find a deal on minis or micros, but I find it easier and cheaper to just pick up a 2- or 3- pack of standard servos at the local hobby store as I drive by. I’ll also stay with the standard servos for the higher torque than the micros, even with the larger size.