Featherweight Discs

I have decided that Ill make improvements on this bot, and will definately keep it for the FW smash.
Because I cant use the weapon (at RC Wars), Id like to ask bots like tantrum and venom (nasty weapons) to not use theirs. Please.
Cheers, Ewan

Oh, to make that clearer, if I could ask nasty weaponed robots to not use their weapons against ME, you can use them against everone else :)
Cheers, ewan

thats fine by me, i dont have a weapon!

take it your not classing Nasty Weapons as flippers?

OK, I know I said I wasnt going to say any more on the subject of spinners but we are past the good humoured exchanges with Ed over his alleged new machine.
What we have here is a situation were there is a very good chance that someone will get seriously hurt!
Ewan, look mate, you are clearly very interested in roboteering and Im pleased to see such enthusiasm. But take it from me, what you have there IS NOT SAFE€¦.END OF ARGUMENT!!
It€™s only my opinion, but what I think you need to do is instead of building multiple machines and running into the same problems each time, just concentrate on one robot€¦and before you even think about picking up a screwdriver, sit down , take several deep breaths and think very carefully about what you realistically want to achieve, given your own abilities, tools and available materials. Yes, you may want to build a Vortex but both you and I both know it ain€™t gonna happen! (yet!)
So try this€¦ forget your spinning whatever€™s (for now) and put all that enthusiasm that you clearly have into building the best chassis and drive you can. Just remember if you aren€™t sure about something there is absolutely no shame in coming to this forum and asking €œcan anyone help me with€¦?€ In fact you would be amazed how many roboteers will be more than happy to help you.
Once you have your running chassis that is strong and reliable as you can make it, even if it has no weapon, bring it along to a Roaming Robots live event. Even if you don€™t want to run it, there will be enough people who will be very happy to take a look and will no doubt offer you much advice as to possible improvements! Again there is nothing wrong with saying €œwhat do you think of this?€ I promise no serious roboteer will ever rip the piss out of what you have done, and in fact you will earn a hell of a lot of respect by doing that. But one small thing to remember, most of the people who will offer you advice know a hell of a lot more about robot building than you do at the moment. I mean no disrespect whatsoever to you by that statement, but it is a fact. So listen to them!
OK, so now you have a solid drive system and that€™s halfway to having a good machine!
At this point there is a couple of ways to go. Take your chassis, add a shed load of armour and a couple of nasty spikes and you instantly have a respectable €˜rambot€™ OK, not the most dangerous machine but a very good starting point for driving practice and you can safely use it in virtually any standard of arena.
The other option is then to add your weapon of choice. If this is going to be a spinner remember what I said at the beginning and BE REALISTIC with what you hope to build and PLEASE ASK if you have the slightest doubt! (one hint, never even think about hanging any kind of spinner on an unsupported motor shaft!)
When you have something you are happy with, again, run it along to a live event and subject it to a proper inspection under FRA rules and hopefully it will pass! If it doesn€™t.. no problem at least you will know what needs attention.
If all this takes 6 months or a year don€™t worry, no one has set a time limit on building a robot, and in the end you will have a robot that you will be proud of and above all is SAFE!!!!.
Good luck, and happy Roboteering,

Geoff.
Team Scorpion.

well said.

Well, I DO use cad for doing first designs on my bots, and I try to have an idea of what I want to build first. I have already gone through the starting stage for roboteering, and entered my last feather into RW (most of you know what happens :)) And I entered the FW smash with a robot before that. If you are coming, or if anyone else is coming to the RC wars event, then Ill show you some videos of me trashing a 6kg industrial bin with Big Daddy. Like it or not, this bot IS safe.

CAD does not make your robot good. Neither does CNC. Your design makes your robot good. CAD just helps you get there.

yes we do know what happened at RW, you drove into the arena and the wheel fell off!

Ewan, so what if you can trash a 6kg bin? It doesnt make your robot safe! Please take note of what people are telling you here. People are giving you good tips but you stear away and still say your way is better. Please take note!

I havent seen the build quality of Ewans machine so I am in no place to say if it is safe or not but i know for a fact that spinners can be run directly off a motor shaft. At Inspire Black and Blue was allowed to run without any concerns been raised about the strength of the axle, this may be because the builder is much older than ewan (and therefore more sensible?) and it survived the entire event (well the spinner did anyway). People seem to like commenting on things that they know very little about. I dont know if Big Daddy is safe or not so I am keeping quiet untill it has been examined in a tech check like every other robot, it is one thing to advise someone that there robot may not pass a tech check to save them turning up to an event and not been allowed to run but telling them that it is not safe fullstop without ever examining it seems a bit OTT.

Joe Townsend

Correction - the motor shaft is supported on the other side Joe. I know it dont look it, but it is. Thats why the other side of the chasis moves funny when you push his blade round with your hand.

Mr Stu

Ewan,
€œLike it or not This robot is safe€€¦.With all due respect, that is a decision that will be made by the Technical Officer at an event ! I really don€™t think you are qualified to make that call.
If you really feel that it€™s safe and is capable of doing what you claim€¦Bring it to the Featherweight Smash at Halesowen in March, or any other live event you wish, and I will be more than happy for you to put it in the arena with my machine.
I will then let my team mate, John, give you a practical lesson in the benefits of a rock solid drive and a properly constructed spinner. (Maybe Stu would like to comment on the probable outcome!)
I have tried to offer constructive criticism based on 4 years of practical robot building involving high speed spinners. Yes, we have had our own problems and the odd failed design over the years but we have learned from our errors and by asking questions were necessary. But if you chose not to take advantage of the huge amount of freely available knowledge within the roboteering community then I€™m Sorry Ewan, that is your loss!

Geoff,
Team Scorpion.

If you drive into a 6kg bin, at full speed, with your weapon going, then you simulate an impact quite well... The motor has some of the biggest needle roller bearings at each end, that I have ever seen...
Oh, and your being ageist :)
Cheers, Ewan (age 12...:))

sorry geoff, I didnt read the word unsupported when talking about the disc. Ive just seen a picture of black and blue and it does have an extra supporting bearing on the other side of the disc. My bad

Joe Townsend

I agree that the technical guy makes the decision in the end, but when you see this bot in the flesh and start to push on certain spots etc, you begin to see its real strength. Oh, and I have just begun to make the motor shaft supported at both ends...
And finally I would like to go against your spinner, I do personally admire it as a very well build machine. Your heavyweight is one mean machine as well...
THE END (maybe):)

Ewan iv said it twice today, stop going on about how you say your robot is great and safe, as Geoff said its not your call. Use the advice people are giving you!

and start to push on certain spots etc, you begin to see its real strength

Im pushing on this drinking glass at the mo that i use to drink out of, seems real strong. But i know it will shatter apart if i put more than 0.5Kj a spinner mounted onto it.

If you want to line up a 1v1 with Scorpion JR at FWSmash you are welcome to Ewan.

I can see if Jonno would allow it to run in his MAIN Roaming robots arena, as i dont think it would damage his arena nor bits fly out when Big Daddy smashes apart. But you running that at home just worrys me. It also maybe a different story when it comes to running that at a small Feather Arena.

I aint saying anything more on this subject. If an event organiser gives you the OK to run ur spinner at their event, then i hope their arena holds up to it when it smashes up, or they get lucky that the disc loses all its energy before it hits the roof/wall.

You have been advised that it does not look safe Ewan, dont be disapointed if you turn up to an event and your told its not safe to run.

Mr Stu

So, from what you have seen already stu, will you let this weapon run at the FW smash?
I run the weapon in a part of my my back garden, which has a concrete floor. When operating it, I put all the switches on etc, and I go to the second floor of my house, I look out (airiel stcking out window) and operate the bot from there. This is as safe as you can get when testing...
I will never run a weapon like this at close range, or in an arena incapable of containing it.
Cheers, Ewan

ewan, a 6kg dustbin doesnt put up as much as fight as another robot.

put dig daddy in with alpha at RCwars. We can see how tuff the robot is then.

Ok, also can Scorpian JNR go through 12mm polycarb?
(Thats how thick the front armour is)

Also worth noting is that the motor in BlacknBlue was fully modded. The internal bearings at either end are bigger and more secure,there are extra cables to the brushes and the original shaft was carefully tapped out and replaced by an 8mm shaft that the local engineering firm gave me. They make gear for rock climbers and said that it was hot rolled high yield steel. The far end of the shaft has a thread cut in and a nyloc nut keeps it together. Nevertheless the shaft was already slightly bent at Inspire, causing more vibration. Ive since replaced it again, but Im on the look out for some chrome-moly steel which which will bend back after big hits. Another factor is how much damage occurs to the shaft when the disk is first attached - In BlacknBlue the blade is attached using the two Tarantorque fittings so no holes or flats are needed on the shaft itself. Im not that happy with the length of the shaft as this weakens it but I cant see a simple way around that.
I think 8mm is OK for big feather disks if supported at both ends but dont expect it to last that long. 12mm or 1/2 would be better.
Despite its apparent strength Ive never run the weapon indoors or in car parks/gardens etc, only in arenas, its far to dangerous. And after Inspire 2002 only if theres a roof on the arena :)
We build lots of feathers in the Young Engineers club at my high school but I wont allow any of the students (inc. sixth formers) to build spinners. None of my students have ever seen BlacknBlue in action - that how careful we are.

Ewan,
I have just spotted your age!€¦I had no idea you are only 12! Now I€™m even more pleased that you are so enthusiastic about robot building. This is exatly what our community needs€¦ Roboteers, The Next Generation!! :) It also explains a few things!.
But that said, It still doesn€™t change my advice to you regarding the dangers of this type weapon, something that you will come to learn in time and I hope its not the hard way.
Please take my, and a lot of other peoples advice and take advantage of the vast amount of knowledge out there€¦Remember, all you have to do is ask.
I€™m sorry if you thought I was being hard on you but all I€™m trying to do is promote a responsible attitude towards safety.
Keep working on that machine but be careful and do some serious work strengthening that spinner mounting.
Oh and by the way, 12 mm of poly will not save you, its not a question of thickness of armour, but how many times can your robot stand the shock of being smashed into the air and crashing down again before something vital breaks. Another thing you will learn about spinners, not all of the damage involves tearing large pieces off your opponent Sometimes the shock of impact on a robots internal parts can kill a machine far quicker than any damage you can do to the outside!
Now you know why I go on about having a rock solid drive and a strong chassis.
So take it easy, and work safely

Geoff,
Team scorpion.

If I have a workshop with a pillar drill and jig-saw machine (dont know the name) at the age of 12... I wonder what Ill have when Im 18 :)
But still, I do take the fact that being 12 does not give you an excuse to build less safely. I will try to upgrade Big Daddy as much as possible, because I still think that it is a workable design. One of the problems about being so young is not having the money to get anything CNCed or using so many good materials. If I could afford a version of vortex, then thats what Id build. If anyone wants to send me money then do so! (yes that is a desparate call for cash!!!) :)
Cheers, Ewan

If you have a bandsaw and a pillar drill you should be able to build a robot very similar to vortex. If you dont think you can machine the bulkheads and baseplate out of aluminium like vortexs then use some of that 12mm polycarb, that can be machined as if it were wood and should be plenty strong enough and a lot lighter. If you manage a copy of vortexs chassis then use a fat bar instead of the disk, dimension it to fit your speed controllers/batteries/motors etc. not Eds then it should be a very impressive robot that costs no more than Big Daddy did. The only part you may need outside help with is the axle that the disc goes on, I imagine lots of people on this forum will have access to a lathe and could whip up an axle to your specs for a small fee. CNC is a luxury not a necessity. As for the good materials I agree with you much more on this point, it can be quite depressing when you hear about the cost of decent grades of titanium but if your build quality is good a robot armoured with 6mm polycarb will be very hard to stop even with a robot like vortex. Like Geoff said above it is normaly the shock breaking the internal workings of the robot rather than cutting through the armour that ends the fight.

Joe Townsend

Its not a bandsaw its a scroll saw...:)
Anyway, Ive fitted a better 2.2mm titanium scoop at the back of the robot, which extends 30cm beyond the back of the bot, I might take on venom and Tantrum afterall. (but still, even at 1/16 power, I do think tantrum- with the weapon- should NOT be allowed in an arena without a roof, even though its horizontal, shrapnel could still go upwards...)
Cheers, Ewan
P.S. The bot is now fully clad in my sponsors logos (http://www.batteryworld.co.ukwww.batteryworld.co.uk) and for the logos sake, the name has gone back to Micro-Maul

Ewan....Remember what we agreed...never mind the Ti scoop and sponsors, what about those weapon mountings!!
Get your priorities right!!
Geoff.

As I have said before, Im only kitting it out for RC wars right now, Ill kit it out for using the weapon (at the FW smash) after Rc wars...

tools dont makethe robot the roboteer does

TX-108 Gianto V1 Gianto v2 Tanto 1 and my previous 3 heavyweights were made with a jig saw a hand drill and file and pretty much nothing else and all of them capapble of taking there own strength and surive a full on attack from all sorts
youd really be amazed what you can achive when you put your mind too it
Recently I got a milling machine and lathe but I dont personally see them as essentials more of a luxury to me

that said I did have to get somethings done outside of my garage I think we all need some help sometimes

Tantrum wont be fightin at RCWars on Sunday Ewan, too busy with all the extra paperwork Ive been lumped with.

For the record by the way, as shaft sizes came up a few posts ago, Tantrum runs a 55mm thick aircraft ali shaft with 4mm titanium thrust retainer. This is in line with the expect 10% guideline on spinner supports from the FRA.

Though many current spinner come nowhere near this, I would not say that makes them unsafe.

Each robot is unique, and each solution should suit that robot. I would suggest for Ewan, as you are always trying to get so much energy in your spinners, that you have a primary support shaft of at least 10% of the disk diameter, this is to meet that expected guideline. If you had a 50mm shaft on you 500mm bar, and the motor shaft plugged in the other side, you would have pretty much the same setup as not, but its held on far better. Not too hard to do, wont compromise your robot either. If you did have this, even with a wooden chsssis Id be 90% sure of running you. Wood is underrated, remember, the Mosquito fighter bomber was wood!

spinners are a very tricky thing to convince people they are safe, if you want to make sure they minimize their critisism, maximize your mounting method.

If your robot is well built, and Im convinced the spinner will not seperate from the robot, its 90% there. The arena is more than capable of containing most spinner (featherweight) but one or two might be just the right size/shape to cause us problems.

As to the roof, again, dont make so much of it, its very close to the top of the arena, as due to feedback from the roboteers, there is now no gap. We can run verticals.

Oh, can you (run vertical spinners), Ill be running it then... The mounting has now been strengthened with an solid 8mm shaft on the other side of the motor shaft (8mm as-well). This is enough as it is supported on both sides and because the spinner doesnt have THAT much energy.
Even if the WHOLE weapon assembly came off (I bet all of you a tenner that it wont :)), I dont think it would cause a serious threat to the arena or anyone around.

Ive had to step the weapon down to 14.4v for this event, for complicated reasons. Also, who is going to this event (inc spectators?).
(list of robots is as follows)-

Micro-Maul 2
G3
Alpha
Rampage
Thuggernaught
Trilibium
Flip!
Venom
Ploughbot
Kenny
Cheers, Ewan
P.S. Cheers, Ewan is not a robot :)

jonno, stu, dave moulds (turbine) and ed are coming without robots.

Which Ed would that be?

The storm 2 guy. Sheeesh this little venue is gona be so crammed full of people....glad im only bringing an ant :) I think Craig danby Is also coming over.

regards
Dave moulds
Team Turbine/PLF

P.S
I belive Kenny has had to pull out, and to all the people asking me why isnt turbine going? basicaly because the chassi is all screwed up and is being re-built atm.

kenny is not bringing a robot but coming to watch.

RC wars went Great guys, well done. The Weapon of Micro-Maul Didnt break off :) but now lots of upgrading is required for march, a new Micro-Maul will be out for the FW smash in March.
Cheers, Ewan

just to revive this thread a bit, i have heard talk about a max rpm rule being introduced, could someone clarify if this is going ahead or not and if it will apply to featherweights. I only ask as my new bot will have a very light but fast (6000rpm) disc.

Joe Townsend

Team Cut Corners

The FRA is proposing a 3 Stage rule about Spinners which effects all weight classes. Although this does not LIMIT the spinners, it just means the robot will need to be subject for REVIEW to see if it is safe enough to run at an event.

Quoted from the FRA Rules :-

Weapons that exceeding any TWO of the three limits must be subject for review -

Spinning element is more than 20% of the robots total weight.
Spins above 500rpm
Spinning element is greater than 24 Inches in diameter.
----
So its not really a max speed or rpm, or weight or energy rule, its more of a safety rule to be honest.

Mr Stu
FRA FeatherWeight Rep