360 - mini hypnodisc

You evil b*****d

Hope it goes well though, could be fun to watch :)
Just hope I'm not on the receiving end :shock:

Not updated this in ages..

Not really been motivated for a while with robot stuff.. since the tag team champs i havnt really been bothered to touch 360, (the tool box is still in my boot) Or get Ed to get onto the CNC for me as we had a previous team member pass away. Sorta changed our perspective of the hobby abit i think.

Anyhow, Due to the new materials being mega tuff, ive had to get Kenny to machine me a new disc rim as hes got access to some pretty good carbide tips. The disc is still being finnished off at the moment.

Its 16mm thick (up from 11.5) and will weigh about 500grams more.. The teeth will be 6mm thick. (chamfered down from the original 16mm)

Its made from P20 tool steel and is going to be nitride coated. The disc rim is costing me a bomb, so im kinda hoping its all going to pay of and be the first disc on a feather to slice through hardox. On paper nitride coated P20 should go through hardox as its double the rockwell rating... plus the fact its got 5kg behind it traveling at about 4000rpm.. The old hardox rim did cut through hardox just about.. but thats not really good enough for me.

Pics curtasy of kenny soon :)

Still no progress on the self-righter...

And yes the new disc will have the spiral :)..

http://i685.photobucket.com/albums/v...ulds/disc4.jpg
CAD

http://i685.photobucket.com/albums/v...ulds/disc3.jpg
Centre droped- the centre offcut is bigger in diamater then garys new disc is overall :P

http://i685.photobucket.com/albums/v...ulds/disc2.jpg

http://i685.photobucket.com/albums/v...ulds/disc1.jpg
Counter bores for mounting to centre are started

http://i685.photobucket.com/albums/v...ulds/disc5.jpg
The old titanium centre fits snug into the new P20 rim :) (rim still needs profiling with the chamfer put on- might get kenny to engrave 360 into the teeth aswell, for the added pimp effect lol.

ditto Jamie :rofl:

ditto clive
its going to end in tears ;(

6mms still too thin dude - go thicker at the tip.....
should be good when its done

Dave,

Please be aware that when you nitride steel you not only make the surface hard but also more brittle. Personally I would expect any sharp edges you have on the disc teeth to chip when it comes into contact with something like hardox. It will probably give off some nice sparks though. After all nitriding is designed to protect components from wear not impact. Just my opinion.

Ian.

all the edges will have a radius

Even the tip of the teeth? Thats where he means will chip off.
I'm not sure what that P20 materials like, but I would expect the tips still to chip off pretty quickly - although if the nitride coating is only done really thin it wont matter anyway as that tip would have dented off (or with 6mm thick tip folded off :proud: ).

The teeth will have a 1mm radius on the very tip, not much just to stop abit of wear..

Still got some time to think about hardening and stuff yet as the rims still not finnished..

Little spinners teeth at the last event were case hardened P20.. when they hit satanix they dug about 5mm into the mild steel then snaped there own titanium bar/disc... the p20 didnt even scuff.

P20 would work nicely without any treatment.. The nitride would only be a thin coating.. Not thick enough to make it brittle. just tuffer. I might case harden then..

Im deffo keeping the teeth at 6mm thick. any thicker then the entire purpose of this disc is pointless (it was designed to slice hardox- any thicker and it wont- i mayaswell of kept the old rim, if it breaks in the process.. then so be it) Has anyone got any hardening/casing suggestions?

Quote:

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Little spinners teeth at the last event were case hardened P20.. when they hit satanix they dug about 5mm into the mild steel then snaped there own titanium bar/disc... the p20 didnt even scuff.

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I can see what your saying and I wouldn't expect the P20 to show any signs of damage against mild steel either. The reason being mild steel has a Brinell hardness of about 120 with sod all alloys but Hardox will have a minimum of 400 Brinell with lots of alloys and is designed to be wear and impact resistant so the results could be different.

I was only suggesting that hard edges could chip and therefore lose the nitrided layer and expose the softer material underneath.

I am actually quite intrigued to find out what the effects would be and how nitrided P20 would stand up.

My interest comes from the fact that I do heat treatment for a living, in fact I work here http://ht.bodycote.com/?OB=81&POB=276&ID=352


Ian

http://www.westyorkssteel.com/P20.html

Im just working from that site and the idea's kennys given me. Hardox 450 has a rockwell hardness of 45, nitride coated p20 should be around double that im told.. thats all ive been going off. apparently case hardened p20 should give a Rockwell of C55/59 if done right. Which should be enough.. but for abit more i thought the nitride would be a little better.

Ian, What would you suggest then? If you can sort somthing out for us that you think is going to be the best solution and post it on here ill get it sent to your company if you can get us a quote, or do it of the back of the lorry ;) have you worked with P20 before? I think its used for a lot of press tools.

Dont do it Ian, he might just try it out on Dinah. :lol:

Hmm...P20, you say. Sounds tough enough, though possibly brittle. How good is the strength-to-weight ratio against Hardox alloys

[perhaps I should open another thread for this... :proud:]

Um...360 rules by the way. :proud: Nice pics and renderings too. :)

it isn't brittle its a shock tool steel used in alot of press tools where tools are hit together with like 200 tonnes 24/7 365 days a year, for years and years

P20 compaired to Hardox...

Hardox is alot softer. p20 is a tool steel.. you use tool steel to machine hardox :)

I dont really see the point in compairing.. not many people would bother buying p20, its to expensive and it carnt be bought in thin sheet, and i dont want to many people buying it if it works :P garys already gone and done it lol.

Its also not easily machinable, I had to get Kenny to machine it as machining tool steel is part of his job, even Ed wallace wouldnt of been able to machine it due to needing real high quality tips to work with it.

As for price.. My disc has cost 430.. just for the rim, without hardening.

But if anyone's interested theres a round offcut for sale lol

I think THZ's nasty axe is nitride coated tool steel. I could be wrong? (John?) but that takes a hell of alot of shock.. and doesnt seem to break.

Even if the nitride coating comes away in small chunks it doesn't matter. The P20 underneath will be more than enough to do suitable damage.

My hardox disc on hornet 2 took a hell of a hammering through the 6 events it was at and I ended up having to remove around 3 to 4mm of material off the original single tooth with grinding it down. I seriously doubt I'll have to do anywhere near the same with my P20 disc.

If you don't believe that P20 will do well in the arena I'll be only too happy to throw my next featherweight in with yours and we will see which comes out better. Best of luck shattering the 1inch thick disc :)

Quote:

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But if anyone's interested theres a round offcut for sale lol

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Just cut two of these out and that'll be me partially sorted for the drum of Drumroll II:[attachment=0:3jyu8q5s]drum_disc_sketch.JPG[/attachment:3jyu8q5s]

:D :D :D

...drumroll 2 :shock: uhoh....

Just to throw a bit more information into the arena :crazy: , P20 in it's as bought state is about 300 Brinell which is about 33 Rockwell C scale. Hardox is designated by its Brinell hardness so Hardox 450 is about 450 Brinell which equates to about 47 Rockwell C scale. When you nitride P20 it will give a surface hardness of around 650 Hardness Vickers which equates to about 56 Rockwell C scale whilst retaining the original core hardness, this is what makes so P20 suitable for nitriding. :crazy:

Heres are a couple of more links for P20

http://www.schmolz-bickenbach.com/fi...PLAST_2311.pdf

http://www.carrs-tool.co.uk/products/P20Spec.htm

and one for hardness conversion

http://en.wikipedia.org/wiki/Hardness_comparison

I'm still looking forward to seeing it in action. :D

PM sent.

Thanks for the links Ian, very useful. 65 rockwell would be about right.

and dont worry you will see it in action ;)

kennys done abit more;

http://i685.photobucket.com/albums/v.../davesdisc.jpg

just needs the profile doing then its ready for a week in an oven at 510 degrees followed by an acid pickle :)

Quick Dave, go single tooth befor the profiles milled in :proud:

nah dont really see the point, it doesnt have any engagement problems as it is, and it weighs more with two teeth.

Small update-

The 10mm thick en24 gears have arrived for my selfwrighter and works being done on that atm, hopefully they wont strip.

Also kennys finnished profiling my disc now just needs 360 engraving on it and nitride coating;

http://i685.photobucket.com/albums/v...ds/discwin.jpg

http://i685.photobucket.com/albums/v...s/discwin2.jpg

:) Looks good! Whats the weight now?
How deep is 360 being engraved? want it as shallow as possible so you dont loose extra weight :D

the engraving will be done 0.5mm deep with a small ballnose cutter so will have a nice raduis

Shiny 8)

Something tells me it won't stay that way for very long :)

Weight I'm not to sure about if it weighs to much I'll surface grind some material of the bottom until it weighs what I want.

As for shiney... It's going to turn black when it gets coated I pressume. Not sure. The disc centres getting a nice paintjob though :)

It will be grey after nitriding. 8)

im not entirely sure this is possible but that think would like awesome anodized 8) .

:roll:

is nitriding the same as anodizing ?

:uhoh:

Anodizing is for coating aluminium in a chosen colour. Nitride coating isn't for cosmetics, it's to make the surface of the material harder. I won't be painting the disc rim when it's done. The disc centre is going to have a candy red spiral painted on with skulls airbrushed into it, then the hole disc will be lacured.

That sounds an awesome paint job :)

I want to get Satanix fully painted simaler to Hooligan, need to get it running first :)

Is Tom Armitage doing your sprial perchance ? ;)

Sounds good :). Just one thing though - we tried laquering one of our robots, and it looked terrible as soon as it got lightly scrateched - tell to just laquer the spiral bit :proud:

Would just like to say thanks to whoever voted 360 as the overall best engineered robot for 2009. Ive genuinely got no idea who you are- So thanks! :) Thanks to all the help from ;

Ed Wallace- Grange Square engineering - CNC work
Andrew Kenworthy- ALK engineering - Heavy duty CNC work
Grant, James and Nick Cooper- Priory Castors and Robochallenge - Workshop use and a few odd bits of machine work.
And Tony from http://www.titanium.com - Materials

360 wouldnt be possible without them.

Update on progress coming soon!

Look forward to seeing it go with the new disc kenny made - saw it at the weekend and it looks pretty nice :proud:

and a few odd bits of machine work :rofl: more hours in that than ploughbot lol....