spinner bar ratio

[Danjr1]

had a quote of £72 for a 5kg hardox bar which is pretty decent. is hardox 400 a good grade?

[maddox10]

Ok, thanks. Who's SSAB?

3 seconds on Google

[maddox10]

had a quote of £72 for a 5kg hardox bar which is pretty decent. is hardox 400 a good grade?

72/5= £15 per kilo. If the size is exactly what you want, good deal.
If not, then you can ask yourself, what will I need to work this stuff?

And there ain't no bad grade of hardox. Its good or better.

[Danjr1]

it would be what i want. would just need the axle hole drilled and the pulleys attached. also some bearings in there. I've taken the density of hardox as approx. 7.86g per cu.cm. that correct?

[maddox10]

That weight is correct.

Now, how are you going to drill holes accuratly enough for bearings in something that is about as hard as a cheap drill from an avarage DIY?

[Danjr1]

Outsource the machining work.

[jonny]

you'll never be able to drill a hole large enough to fit bearings into. a 20mm bore bearing will be roughly about 40mm diameter (or atleast the one i'm looking at is). drilling a 5mm hole through 5mm hardox 400 is a pita even with plenty of coolant and a good pillar drill. if you have access to a medium-heavy duty cnc milling machine with decent tooling you could mill a 40mm hole. if you have access to waterjetting facilities you could waterjet the hole.

where are you buying this hardox? jl steel, mtl steel and steelpro all have cutting/machining facilities. you'd probably be best seeing if they can do the work. alternatively kenny should be able to mill the hole out for you. i knew a really good waterjetting company in kent but i'm afraid i've forgotten there name

[jonny]

here's a link to the company in kent i was talking about: http://www.mlfabcuts.co.uk/

[Danjr1]

They ain't far from me. Was thinking of a 12 to 14mm Steel axle for it to spin on with bearings pressed into the bar

[jonny]

i'd go for 20mm myself as the shaft has to take alot of force and you should be getting a crazy amount of ke from a 5kg 40cm bar, 12mm or 14mm could bend after a big hit and break your weapon system