Featherweight Discs

[knightrous]

Featherweight Discs

lol, Im glad Im not over there right now :P
My spinner is exceeding all three
a 4kg rotor(33% of the robots weight)
Spins at around 2000rpm
around 70cm in diameter

Just about to replace a lot of aluminium armour with policarb now to fit the new weapon motor in.

[fwsorg]

Featherweight Discs

My input to those rules- at least for featherweights- dont agree with them. 20% of 12kg is 2.4kg. There are a LOT of feather spinners whose discs weigh more that 2.4kg! 500rpm- very very slow by featherweight standards.
24- OK not so much an issue with feathers, but it strikes me that one size limit applied to all the weight classes contradicts the claim that this rule is made with all weight classes in mind.

This needs further discussion on this thread for featherweight builders- most decent feather spinners will exceed 2 of those limits. It is too much hassle and red tape to have most good feather spinners subject to review, whatever that may entail.

Just some thoughts.

[s8nsmum]

Featherweight Discs

all spinners whether big, small, fast or slow will be reviewed by the tech check people at an event anyway, i dont see what this rule accomplishes. If someone turned up with a 23.9 diameter, 2.39Kg disc that runs at 20,000rpm does this new rule mean it would automatically be safe? surely the same rules will apply to it now as always did, if it is safe to run it will run, if it isnt it wont. Or is this a seperate review where it has to do a spin test and drive into the side of the arena to see if it is strong enough or something, i dont mean to be pedantic i just want to know where i stand as my new featherweight spinner will be subject for review (if it ever gets built).

Joe Townsend
Team Cut Corners

[tim_jones]

Featherweight Discs

I really do think that this makes sense for feathers in most repects.

Lets be honest if your robot is to hold down a disc weighing over 20% of its weight and spinning at over 500rpm, you are either spending serious money on lightweight bits, a fantastic engineer or you just dont care about safety!! Most of us dont have bottomless pockets and sadly arent superengineer himself, therefore some form of peer review of our often hare-brained weopon systems is a highly wise precaution.

My first thought was that this was a simple and fair but effective means of evaluating feather spinners, nothing anyone else has said since has convinced me that it is anything else. It may even not be restrictive enough.

Regards

Tim Jones
Team Bernard

[fwsorg]

Featherweight Discs

I dont think thats the case at all. Mag motor aside, the weapon system on vortex is really quite simple- anyone with some skill on a lathe and mill wouldnt have too much of a problem building a similar thing! Granted if one is building something like this is a basic workshop (woodworking tools, jigsaw, that kind of thing) then it may be an issue, but the second you gain access to a lathe and mill, as many people have, its a whole different ball game! It should be down to the EO as to what they feel is safe to run in their arena- there are just too many variables in spinner construction to have the entire weapon calss governed by 3 statements.

Its simply not the case that you are either spending serious money on lightweight bits, a fantastic engineer or you just dont care about safety!!

I have built the spinning mechanism for my feather for about £80. A dewalt 24V (£30), timing pulleys courtessy of RS, and the disc is machined form a motorbike breaking disc- very strong and tough stuff as my HSS lathe bit will attest! It has a 20mm silver steel axle, supported on both sides by 20mm needle roller bearings, mounted in 15mm thick 6082 bulkheads. Disc weighs about 3kg and spins at about 3000rpm. The disc spins indredibly smoothly- no vibration. It is very very solid indeed. It was made in my school workshop in my free time. It does not use expensive lightweight parts, I am definatelly not a fantastic engineer, and I can assure you Ive built it as solidly as i possibly can! I will not say its safe because no spinning weapons are. I have a very high regard for safety, which is why i treat the thing as if it could explode at any secong, even tho I know is build like a brick Sh!t-house. Its entirely possible to build a safe spinner whilst still exceeding the limits given above.

I know its a different ball game in heavies- scaling that up to heavyweight, wed have a 30kg spinner spinning at 3000rpm- which would be terrifying and enormously dangerous, but it isnt in featherweights. And if we go even smaller, Pete Wallers antweight spinners can weigh up to about 40g of 150g limit, and spin at about 20,000rpm! As you get smaller, the RPMs increase. This is why I dont think those rules can be applies to all weight classes. They work fine for heavies, but not for feathers or anything smaller.

[jas]

Featherweight Discs

I think people are becomming Spinnerist.

If the robot passes its tech check isnt it enough to say its safe?

arent flipping arms or axes just as dangerous???

Limiting what a Spinner is allowed is like making your own rules! All the speeds and weight.size limits are not right for ALL weight classes! This includes Antweights as well :S

I think its appropriate for heavyweights and middleweights (who cant currently use spinner weapons at most live events). But Lightweights, Featherweights and Antweights are different. There is no reason to change the rules! If something works well dont change it.

If these rules do come into place then I hope that other weapon types get rule changes as well!

Jas

[stu]

Featherweight Discs

If you would all like me to bring it up at the next FRA meeting taking place this weekend, then i will. If anybody would like to email me with their concerns, or questions that they want answering, then i can take it up and try and find you some answers for you.
Email me at stu@featherweights.org

Mr Stu
FRA Featherweight Rep

[fwsorg]

Featherweight Discs

Its all here Stu on this page.

[tim_jones]

Featherweight Discs

Eddy well done you have built your spinner for small money, but dont forget to factor in the cost of the tools you have free access to. For many of us that is a serious money issue! Without the money tools or access to free bits, a set of limits within which you are not subject to a major review is to be welcomed.

I applaud those who push the limits, but in reality your situation will have changed very little, you always were going to be subject to review. Why object to a sub-class of spinner for those of us who are less fortunate and just cant afford to push the limits with the risk that our weopon will be declared unfit to run?


Regards

Tim Jones

[jamesb]

Featherweight Discs

its kinda true that it need holding back, as to be honest, both me and Ed Hoppitt have held back with our previous spinners.

Ed never (to my knowledge) run his mag at full voltage, or at full throttle on full voltage anyway, and Tantrum never approached his 24v design as 12v was too much.

as it stands, with my current workshp and knowledge and within 3 months with £400, I could have a 4kg 500mm disc at 10,000rpm reachable inside 5 seconds, but whats the point? Nobody will fight it, Id be filling my pants the whole time its plugged in, and it probably wont be allowed to run.

So, instead of setting strict rules we should advise common sense, as if your spinner hits hard enough to damage good robots, expect to be looked at closely. If it can wreak good robots, expect problems, and if nothing can take a hit from it, dont expect to run. If you want to be 100% sure of running your disc, make it a nibbler, not a muncher.

[tim_jones]

Featherweight Discs

James I guess Im kind of unique then. We need spinners! Shovebots and flippers make very boring opponents. What is the point of turning an invertible robot over? If I wanted that sort of excitement Id be playing tiddlywinks.

As Aber demonstrated without decent spinners you just have to play with the heavies for real excitement and challenge

Regards

Tim

[jamesb]

Featherweight Discs

so true, but what I mean is, if you show up with something rediculous (as Ive done) dont be surprised if its not run.

There are feathers that can take huge hits, and some are more heavily armoured than the arena... I would not want to see tantrum at full power being sent into the screens..... well, actaully I would, but only if I was 20 feet away and I did not own the said screen.

yes, we need spinners, we need powerful spinners, but we dont need stupid spinners. If the heavies cant have them at all, we should have limits, and the limit should not be a quantifiable value, but a common sense judgement on the day, with the actaul figures there to let you know if you can expect to go home early.

my 2 pence

[s8nsmum]

Featherweight Discs

on my new bot i am planning on having two different speeds of disc. firstly i can drive the disc 1:1 of the motor so it will spin at about 4000 rpm, this should be plenty for almost any event, it should nibble at robots pretty well but i doubt if it will cause significant damage (the disc only weighs 1.7kg) or i can change the gear on the motor and drive it at 1:2 against the motor hopefully giving it about 7000 rpm. this will only be used if taking on robots with similarly powerful weapons. It is always a good idea to have a backup plan if you think there may be a problem with your disc as something as simple as changing a gear and a tensioner may allow you to run. Similarly you could have a competition disc and a fun disc, i think razor do something similar with their hydrolic setup. Any robot should be able to tone down their weapon so i say build a robot to the limit of what you think will be safe but be prepared to change it if the powers that be disagree

Joe Townsend

[fwsorg]

Featherweight Discs

I agree with above. There is nothing stoping anyone being rediculous and building a 36V mag power 4-5kg spinner- its entirely acheivable within the weight limit- but very few areans would hold it, and few roboteers would be willing to fight against it. As james said, common sense should be applied, or at least a clause to the effect of If you have the time and money, by all means, its your call, but be prepared to not be allowed to fight it. Tis a difficult issue. Spinners like tornados, which are effective but not rediculous as the complement the rest of the robot, as opposed to BEING the robot, are good direction to head, but then its always fun to have all-out spinners. Our March 6th event will be a good opportunity to see whats going on, and perhaps debate the next move etc. Thoughts?

[robjones]

Featherweight Discs

My thought are spinners are what the crowds love.....but we need some good axe-wielding featherweights.