Tashic's Robots

[Tashic]

Yesterday I sent an email to direct plastics to see if sending to italy is possible, I'm now waiting a respones.

Only if that fails I will use polycarb, and not only I can get that near home, but they can also cut the parts for me.

But I hope to get the HDPE instead.

[mrsam]

Bit late but still, Polycarb isn't the best material to use as you can see from Hatchet, to put it into perspective that was a 10mm thick piece that shattered into 3 pieces from just landing on top of a spinner at about half it's throttle. If it's all you can get hold of and you don't plan on using it in spinner combat it will be fine but hdpe is the better option both for impact resistance and weight. Also with regards to the axe motor I'd recommend running it slightly higher, I ran Hatchet's at 16.8v and that swung a 1.5kg axe with a fair bit of force so it depends on how heavy yours is, if it's on the lighter side then you might need the extra speed you'd get from a voltage increase, lastly if you're planning to use chain and sprockets stay away from the 6mm stuff and go for the 8mm, Hatchet broke a chain in almost every fight and it gets a bit annoying having to replace/fix chains all of the time.

[Tashic]

Hi, I might found a way of getting the HDPE, for now I got 2 new drills to add to the ones in Black Wood, now I need to know what capacity the battery needs to be, since a friend of mine is ordering from hobby king.
Is this one fine?:http://www.hobbyking.com/hobbyking/s...case_pack.html
later is going to be the weapon motor.

[Niels - Team K.a.L.M.]

A lot of feathers do with just 2000 to 3000mah packs.

5000mah will be more than you need. Bulls it runs on one and can do 2 fights easily on them while using the big s900's.
With that 20c rating you'll be able to safely pull a 100a without damaging your Lipo and a pair of drill motors won't draw that much.

If you've got the weight to use that one comfortably go for it, or look for another with an higher C rating. Should you add a scooter motor for an axe or upgrade your drives it will help to be able to draw even more amps.

[Flag Captured]

I ran HW2 on an almost identical pack (just a higher C rate, everything else was the same) and I barely even had to charge it after each fight, and that has two Speed 900 style motors in it. My driving style hardly involves me going easy on the throttle either!

It depends on how you are for weight and size really as Niels said, if you have plenty of weight left over that couldn't reasonably used for added armour or anything, go for it - it's much handier to have that bigger capacity than have to be worrying with a low capacity pack. And if you take part in any events that are in the style of this year's Gladiator tournament at the UK FW Champs, you'll be at a much bigger advantage than usual too!

[maddox10]

On HDPE, I can supply the stuff easely enough. But P&P is an additional cost from Belgium. PM me about sizes and cost.

[Tashic]

Hi all!
I will pm you when I solved some other things.
Meanwhile what material should I make the base?
I'm thinking of steel, but what thickness?

[maddox10]

A full steel baseplate is heavy. Thinner than 2mm is just waiting to be crumbled like a tin can.

Best case is to use 3.2mm Hardox, still the weight of steel, but way stronger.
A sheet of 200*200*3.2mm weights 1 kg. An avarage feather is 300*400mm, resulting in 3 kg baseplate.

[Tashic]

Did some testing these last few days, by making this platform:
IMG_3432.jpgIMG_3433.jpg
the motor holders are made out of 3mm steel, if it turns out to be too heavy, I might make them out of HDPE.
The wheels are made using slices of go-kart tyres which I screwed them to the wheels:
IMG_3435.jpgIMG_3436.jpg
The go-kart rubber is very grippy! When I try to push the robot, the wheels don't slide but they turn the motors.
The problem is that leaving them this wide, the wheels aren't perfectly round, but they flex with the weight.

Also the scooter motor had arrived, and I will do some tests on that later.

[Tashic]

Updates:

Started the build by getting the base and making the axe mechanism:
IMG_3460.JPGIMG_3459.JPGIMG_3462.JPGIMG_3468.JPG

Right now it weights 8,5kg including the axe, the gear ratio for it is 5:1, having on the handle 55 teeth and on the motor 11.
The base is 2,5mm steel and the dimentions are 315mm X 370mm not counting the slots for the wheels.

This is what (hopefully) it's going to look:
Cattura.PNG

I decided to make a lower body (kind of looks like K2 now), to save weight, and the scooter motor is closer to the center:
Cattura2.PNG

I will think of a cover for it later.

[harry hills]

Thats a real nice drivetrain there. Will be interesting to see the robot finished.

[Tashic]

So, some time ago I found a place to get the HDPE from italy, and 2 days ago I ordered some sheets.
I thought that the parcel would arrive next week, but after school I found them in the living room:

IMG_3469.JPG
Wow they look chunkier than I thought!!

They are two 20mm black sheets and two 10mm white (they only sell the 20mm sheets in black).
I only really need one of each but I wanted some more to use them when needed.
So hopefully I will make some progress these days.

One more thing, what insert do you use and how you "insert" them in the HDPE?

Edit:
Little bit of progress, I made the supports for the axe out of wood, after I made some modifications to the very cheap jigsaw:
IMG_3471.JPGIMG_3472.JPGIMG_3473.JPG
I also need to shorten the chain, like a lot! Which means some spares.

Also about the inserts, are these good?:
IMG_3474.jpg

Or I need ones without the lip?

[harry hills]

Nice progress mate. Look forward to seeing the finished robot. Might want a bigger shaft on the axe though? What size is the current one?

[Tashic]

Thanks, the shaft is 1cm diameter.

[Flag Captured]

Yeah you probably want a bit more on that. Maybe try for 20mm if you can manage it? I don't own an axe bot myself but I seem to recall Hatchet's shaft being 15-20mm...