Im designing a 2mm thick mild steel cabinet to house some teckky stuff in. I need to make the cabinet out of 3 layers. outer layer mild steel then the middle layer needs to be a material that drills will not drill through, then the inner layer made from steel.
I know some drill bits cant drill wood. apart from wood wot else can i use?
also know you can just about buy drill bits that can trill through anything.

Ray

A ball-bearing and gell compound which just spins when attacked by a drill bit ;)

Diamond ;)

Steve

How do I sandwich ball-bearings and gel between metal sheet?

cost is a problem. will need to make 10 of these a month.

[Edited by Ray_li - 11/27/2003 9:51:04 PM]

There's not a lot of materials that can't be drilled through with the right equipment.
If weight isn't an issue try a thicker gauge in 316-grade stainless.

Ray_li: you really expect people here to tell you how to make drill-proof speed cameras? :eek:

Stick with wood, mate. Wood's definitely drill-proof.

A.

lol :D:D. trust me mate I dont want this job any more but its good for my first years work experience.
The buggers are drilling a hole then filling it up with petrol and blowing the things up.:D:D

[Edited by Ray_li - 11/27/2003 10:00:51 PM]

Hmmm... tricky one. I'm looking for a new job and have just been put forward for a vacancy with a company that makes traffic 'management' equipment. Whilst I couldn't complain about doing motorway signs and pelican crossings, I simply couldn't do speed cameras or other technology that could be misused in the same way. I have the same conscientious objection that I'd have working for the military - with the added disincentive that I would be the potential victim of my own efforts!

My advice would be not to bother - there's plenty of ways to wreck a piece of kit like a speed camera. The Dutch are the experts, I believe. Even if you make the case drill proof, I doubt you'll make the lens fireproof...

I *could* tell you how to make it drill proof, but if I did that then I would also have to tell everyone the way to defeat it, so there is no point :D

try bubble wrap...that should do the trick

Case-hardened steel would surely do the trick?

If u making speed cameras then [img]images/smilies/mad.gif[/img]

maybe a thin smearing of blue eyed babies would prevent people drilling .. ;)

:D

Beggars can't be choosers. I've worked for companies that make Weapons of Mass Destruction :eek:
Well, perhaps not WoMD but certainly the Sidewinder, AMRAAM, Patriot, bits of the Rapier, etc.

Carl, I used to work on Tornado radars - foxhunter.. nice to see the mention of AMRAAM ;)

A 1" layer of nitrocellulose between the skins would do it.

Hey, the Tornado went for its preliminary flight trials with concrete ballast in the nose instead of the radar, because it was delivered late. IIRC that was a GEC-Marconi job, wasn't it? I worked at Raytheon, and there were four sorts of people there:
People who'd come straight from university (like me), or straight from school
People who'd worked at Marconi
People who'd worked at BAe
People who'd worked at STC/BNR/Nortel/whatever they were called this week

The way I see it. If people want to blow these things up go a head Iv got 3 points for doing 35mph in a 30 zone the second week I started work. I NO NOT LIKE SPEED CAMERAS but its just a job since iv just finished uni and realy need the one year experience. after my year is up im out of there, but for now I have a job to do. just bcuz i dont like the product it does not mean i do not give it 100%.

If you do give me info on how to make them drill proof you can tell evryone how to drill it. As long as I had in my work at the end of the day its ok with me :)

Ray

ah, gun cotton and old favourite! :D

Some tri-nitrogen iodide would also work wonders and easy to make too! ;)

Why not try titanium if steel is no good (half the mass too). Grade 5 is pretty tough (available in sheet form) and you'll need carbide tipped/solid carbide drill bits to work on it properly. Regular HSS will have a really tough time. If titanium is good then it may be worth looking into some other grades for more suitability.

Hope this helps

hes a sell out

hes no better then that butler burrel
hang your head in shame

Am i correct in saying that glass is pretty much drill proof - as in, it is jolly hard to drill a neat hole in it? ;)

Problem solved :D

mb

Carbon fibre sheeting, with no bonding agents. When you drill through the outer case the drill gets snagged in the fibres, the twisting action of the drill coils the fibres, and breaks your wrist. You can eventually get through but its a pain in the ar5e.
After you have snagged on the fibres, because the end of the drill is coiled up in the stuff, you cant pull the drill bit out of the hole. Like I said you can get through but it takes ages.

Forward, reverse, forward, reverse, forward, reverse.......

By that time your knicked.

PS. Dont ask...........

Same method used by anti-chainsaw clothing I think.

[pops out of hole]

Arrrrrrgh !!!. Can my defence be that I only skim read the replies :(

Having re-read I've now realised what I've done. Thought I was being helpful :(

[/pops back in hole]

I guess you'd want to use dissimilar materials in the construction so that no one drill bit would be suited to all materials. Stainless steel is pretty touch, aircraft grade. The type of bit you'd want for stainless would not be good for aluminium alloy (it sort of clogs the bit). I like the sound of carbon fibre (good 'un Yoza), chuck in some titanium as well. A ceramic layer would also prove problematic. Oh yeah, those glass or plastic lenses would be a weakness, so remove them.

On second thoughts, why not just call CHUBB ? ;)

[Edited by Brit_in_Japan - 11/28/2003 3:51:18 AM]

thanks guys. some useful info there. will give it a go.
just want to say im currently looking for a new job.

Ray

You may be able to make a speed camera drill-proof, but you will really struggle to make it Range-Rover proof ! ;)

I'd agree with the anti-chainsaw material idea. Saw it on TV once and it gummed up a chainsaw in seconds (all the fibres come out and wrapped everything up). If you got in touch with the manufacturers, I'm sure they'd be delighted to have another market to sell to.

Remember to leave a small area unguarded though, for, er, maintenance purposes. Shall we say, in the bottom left back corner? Good lad! ;)

Make it as strong as you like..... where there is a will there is a way...... ;)

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