Team Invade's Build Diary

[Team Invade]

Fully striped/painted and ready for Thursday!

[Eventorizon]

Aren't you going to give the champ a lick of paint? Surely she has earned it!

[razerdave]

Apparently he is on the limit, and can't fill the tank fully if he paints it :P

[Team Invade]

It's tape not paint, and more tape means it is heavier which means less gas! Even without any tape on the flipper I doubt there'd be enough weight for a full 600g.

And it's always got scratches on it so it doesn't look right when it's freshly done

[Team Invade]

So Combustion came out of the champs relatively undamaged.

I've uploaded a couple of it's fights here: https://www.youtube.com/user/TeamInvade/videos




A few scratches and nicks out of the hardox but nothing more. Overall I'm really happy with it besides the disc cutting out in each fight. There were a variety of issues that arose and most of them got solved:

First of all the weapons link (anderson) kept on coming out due to the metal contacts inside becoming quite hot and hence too loose. So that has now been made into a "double link" (4x connectors instead of 2), and that seems to have solved the problem.

Then the disc stopped after we had sorted that out due to a dodgy connector on one of the lipos and so that got replaced.

The third issue that arose was due to the lipos themselves (these: http://www.hobbyking.com/hobbyking/s..._5S1P_40C.html) which have now been pointed out to us as one of the rubbish brands and best not to use. These worked fine for the drive, but were over-discharged by the weapon motor and caused the weapon to cut out. When we took them out they were very hot and had swollen (though shrunk again when they cooled down), so I think that's probably a good enough indication to change them!

So I need to find some better lipos to use for next year. The obvious place to start is OptiPower based on everyone's recommendations, but having looked, there are none of a suitable size. The smallest 5 cell lipos they sell are 3650mah, which is a big increase from the 2200mah lipos currently in the robot (two packs, one for the drive and one for the weapon), and so will not fit without major modifications.

The next best option I found were these: http://www.giantshark.co.uk/product/...s-lipo-battery

According to the statistics (if they are true) these should be a good upgrade; 55C up from 40C (according to hobbyking) and 110C burst up from 50C. But again I'm not too sure if this is reliable or whether these are yet again another rubbish brand. However I do seem to remember some people using Gens Ace lipos so I'm guessing they may be better than the hobbyking brands? Or if anyone has any other suggestions that would be much appreciated.

[Flag Captured]

How close to the weight limit is Combustion? I'm sure you'd rather not, but there's always the opportunity to adjust the internals and/or make the top plate a little higher up to house some slightly larger LiPos? Then you'd be able to go for the Optipower ones which I've heard nothing but good things about - I'm definitely upgrading to them for next year.

There's always the Turnigy ones, but I'm not sure on their quality in the long run... mine was fine, but I only ran it for about 8 fights total, and it barely needed charging (5000mAh) so I can't really comment on how good they are.

Just to say too, Combustion is a pretty terrifying machine - seeing what it did to Rabid's front scoop (I think, anyway) in that whiteboard, I'm pretty glad I only got one hit from that disc before it stopped... Would you be entering it in the champs next year instead of/alongside Explosion?

[Team Invade]

It currently weighs 12.6kg so plenty of weight to spare. Increasing the height wouldn't really help, the main problem is that there are 11.5cm long spaces for lipos (approximately), and even the smallest 6 cell OptiPower lipos are around 2cm too long to fit in there.

The only time it hit Hardwired was when the disc had already started spinning down so it wasn't even a full on hit The problem it seemed to have in later fights was gyro-ing too much which stopped me from driving it as quickly to get better hits. I might look at putting some magnets in to reduce that.

Entering it next year depends what happens Explosion-wise. We haven't got two drivers so entering both isn't possible but it's something I'm considering if Explosion isn't ready

[craig_colliass]

http://www.hobbyking.co.uk/hobbyking...Lipo_Pack.html

Perhaps the above might work I use the 4*6s option to run Gabriel

[Mouldy]

I really wouldnt suggest using turnigy / gens ace / hobyking lipo's in your robot.

How much did you pull from your packs after each fight? The fact you over discharged them is a good indication you need a bigger capacity. On spin-up that scorpion motor will be pulling massive current that the hobyking lipos cant deliver… there fine for most pushy bots etc but in a big spinner there just not up to the job.

If your serious about this robot and want it to do well, good quality lipos are a sound investment. I remember you saying your redbrick kept cutting out due to overheating… this was probably more like the low voltage cut off was kicking in…

[Team Invade]

It was definitely the low voltage cutting out the weapon. On first inspection we thought it might have been overheating due to the lipos and brushless being so hot but on charging the weapon lipo was down to around 20% each time. The drive was only down to about 50% so I was planning to link them together, but ideally a bigger capacity would be better as I know flattening lipos too much isn't good in the long term.

I wasn't planning to get any more rubbishy ones, it would just be easier if there were other good brands bar Optipower with similar sized lipos that would just fit straight into the robot without any modifications. If the OptiPower lipos are the only good option I can make them fit by putting a gap in the Nylon bulkheads for them to fit in to give 20mm more space, and then covering the gap on the other side with a thin piece of Ti. That would mean upping to 6 cell which is no problem for the weapon but means over-voting the drive. Or if worse lipos are okay for the drive just upgrade the weapon lipo.

[Eventorizon]

Gens Ace are good. Binky and Conker have fun them every year with no issues. But I would go Optipower simply because we know how good they are.

[Flag Captured]

That's unfortunate regarding the LiPo spaces, I would suggest 2x 3S batteries but that might just be awkward and needlessly complicated...

I realised that with HardWired too, that's why I'm still quite scared of it now! If you've got some magnets and get that weapon reliability sorted, I think this could be a very strong contender. And it's one of very few verticals that can actually hit HardWired (if you get me on the scoop) so there's that Would definitely love to see it entered in competition if you go that route though, I bet it'll be very strong. Of course, there's always the pedigree of Explosion too and you obviously wouldn't have replaced it in the champs with Combustion, with it being the reigning champ and all!

Definitely upgrade the LiPos where you can though, sounds like the power usage means it'll just be eating through batteries like no tomorrow and that's not ideal!

[Mouldy]

Opti and thunderpower are the only brands i trust.

[Flag Captured]

I guess it just depends on your machine, I've done mine on quite a low budget and for all intents and purposes, the Turnigy ones seem fine for my rambot*. Certainly wouldn't go as far as saying I trust it though, especially considering I haven't truly pushed it yet - I think it has a non-burst discharge rate of 150 or something and I've been nowhere near that up till now... The Optipowers on the other hand I would trust entirely based on what other people have told me about them and how they've performed in other people's machines... Definitely best if you're running something like a spinner which will be drawing high amps.

*Actually, I've just checked mine now, seems to have gotten some quite heavy wear... never mind what I said! Will still be using it for testing/my old machine but I don't think I'd trust it to not break in another competition...