The stainless might be right yet, just getting a confirmation on the ACTUAL grade from the supplier.

I'll have a google around about the Neumotors, but brushless is something I'm trying to avoid
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Um, why the fascination with stainless? It doesn't really have better properties than many other cheaper steels except it looks prettier (a big factor, I will admit). Move on to a softer grade of Bisalloy or get 4140 hardened after machining - cheaper, easier to fabricate and higher spec. I have no idea what shape the part is, however I have some 8mm thick Ti plate that might fit, going relatively cheaply...
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

I hate to be a sneaky bugger and keep all the details it in the dark, but stainless I can work with, 4140 with some hardening would work, but I fear it might shatter if hardened in correctly. The stainless isn't being used for the puurdy factor, infact that stainless is extremely dull... Maybe a polish when it's done.

Using stainless as I have stainless welding wire to weld the Hardox and welds will be critical on the weapon, I'll have many many hours with the mig, or get the engineers to zap it for me.
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Woot. Some progress.
Been into the engineering shop, we talked a few things and they have some of the parts I need in stock. I've decided that since Glen tortured his brushless at Battleshed without destroying the controller, I will now invest in one myself...

I'm looking at this configuration to power the weapon.

The Towerpro 4130-8T motor coupled with the OEMRC Sentilon100A HV 2-12S Speed Controller Brushless controller.

I would go a bigger motor, but I don't have the weight for it

Since I need to be able to reverse the weapon, I'll be installing a DPDT relay triggered from PicAXE interface board that will provide the controller with the correct signal and give a dead band for reversing the relay and preventing anything nasty. I'm hoping a 30amp DPDT will survive since it will be switching under no load, but worst case, I look at making one myself.

After seeing the battleshed videos and realising RoboWars could only be 6 months away, I'm really eager to get this bot happening. Would also like to thank FX Jason for the upcoming CNC work Appreciate it mate!
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Progress is slow, mainly because I'm freaked to the max on making a mistake somewhere that will cost me $200-300 later, every calculation, CAD file is checked repeatedly, I know nearly every measurement off the top of my head, in case EMP bombs my house, fragging my PC

Anyway, I've been tinkering with ideas for a while now after seeing Jakes solderless urethane packs, and I've really wanted to make some now that I have A123 cells all over the place. I finally came up with something that should work!



The idea is a pair of 10mm thick UHMW plates that hold the cells in place, inside those plates are 3mm thick copper buzz bars (Would easily take 2000amps...) These bars are spaced 1mm from the cells themselves, in each buzz bar there are two holes, where a brass/copper set screw is firmly tensioned against the cell wall (very carefully, otherwise dinted cells and bust stuff). I'll be interested in building and testing a few of them now. I've also worked out a way to make them modular in single cell form, although it will take up a little more room then I would generally approve, but might be useful where you need to quickly add another cell to a pack or remove one if damaged.

Influenza will use two of these 300gram units in it (I went two 3 cell packs because I need to space the weight evenly across the chassis), for a nice 19.8v @ 600grams of expended weight.

My supercharger and laptop have been paid for now, so I'll be able to purchase the brushless gear for the weapon after the next pay cheque (Rego takes that fortnight's savings ) So I'll hopefully have something to say about that stuff to in relation to the weapon
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Neat! Maybe try Nylon instead of UHMW-PE, it would be stiffer. Also if your going to cut into the plastic(make it thinner than 10mm), maybe also a bit thicker than 10mm. Looking good get to work, make some
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Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.
Albert Einstein.

I agree; 10mm is too thin and will bend out at the ends. I used around 15mm on my soldered packs and the plates definitely warped a bit, which didn't matter as they are soldered.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

Edited the design a bit, just uploaded over the original image, Also have this one to show it with no cells in it.



Have added 4 bolting points to bolt the packs to the chassis.
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what you really have to watch out for is warping with heat.
thats why our current ones have an aluminium backing
your also best of with some kind of "spring" to push into contact regardless of movement
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Mechanical engineers build weapons, civil engineers build targets

What size screws are you using to hold the plates together? I used M4 (which worked well) and I could send you some spare Tee nut inserts that save space and distribute the load better than just using a nut:



very light and they work perfectly in UMHW. I had to buy a box of 100, which is more than I will ever use...

For UMHW, I would make the mounting tabs a bit thicker or even full hight and just recess the screw head.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

I looked at tensioner springs, but they just make the end plates to big and took up too much room in my design. If it works, yay, a bonus, if not, well, shat happens, back to soldering the damn things. Bolting a piece of 3mm aluminium onto the back of them is also a possible fix if they do flex too much.

EDIT: Yeah, they are M4's Nick. I was actually digging through your build thread to find out what those nuts were The tabs probably will be beefed up yet. depends on what I change to the design.
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Same as before, but with 15mm thick cell plates and thicker mounting tabs.. Only 309gram, and thats with me calculating the A123 cells as 75gram each.
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I would go 20mm Nylon. I don't like the idea of mounting a batt pack to a frame with screws. These are just my ideas
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Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.
Albert Einstein.

steady....steady awww crap my cell just poured out on the floor
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A journey of a million miles begins with a single step followed by a hell of a lot of other steps so get walking

20mm starts taking up a bit too much of the surface area of the cell, which I really don't want to do I'm going to pull at pushing rubber grommets into the mounting tabs for a bit of shock protection, then bolt it to a piece of Hardox AKA, the chassis
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