Drilling Stainless

[cgf10]

I want to mount a nav light on the (3 or 4mm)stainless steel plate on top of my A frame. Will I need any special drill bits to make the two holes required for fixing the light mount ?

[chewy]

You shouldn't do but Cobalt/Armour piercing work well.

[cgf10]

thanks Chewy

[martini]

Agree you should get away with hss bits if theyre smallish holes. Couple of tips I would give are keep the rpm's down and apply as much pressure as you safely can instead, also get someone to squirt coolant or water on the tip, if the stainless gets too hot even James Bond won't have anything to touch it!

[cgf10]

Martini - thanks again

[willk]

Originally Posted by martini

Agree you should get away with hss bits if theyre smallish holes. Couple of tips I would give are keep the rpm's down and apply as much pressure as you safely can instead, also get someone to squirt coolant or water on the tip, if the stainless gets too hot even James Bond won't have anything to touch it!

This is top advice. I can confirm all is correct and can only wish that I had asked the question before I wrecked a swathe of destruction through my bit collection and learned this by, well, mostly error

[m chappelow]

With thin stainless plate its sometimes easier and quicker to punch a hole through than drilling it .

[Downhilldai]

Originally Posted by m chappelow

With thin stainless plate its sometimes easier and quicker to punch a hole through than drilling it .

Must be a hell of a punch on you.

[AndrewH]

Don't forget to use a centre punch to mark the position of the hole and stop the drill from slipping - particularly "fun" when you are applying plenty of pressure.

Also I've found the titanium coated drill bits (the gold looking ones) keep their edge a little longer when drilling stainless

Edit: just noticed you are just round the corner from me - give me a shout if you get stuck!

[rjbathgate]

i third the "slow as possible" comment... if u go too fast, the stainless will actually harden as it gets superman hot, and then be almost impossible to drill thru...

even hand drill would be good...

[Sonar]

Use a center punch and start with a smaller drill bit for the first hole
then use a larger drill bit to finish.
and as everyone else has said keep the rpms low .

[Trell]

I agree with everything said, but took some advice from a fabricator who said dont try to drill the hole in one go, drill a bit then let the drill bit and material cool, before drilling some more, I found this worked quite well, and drills tend to last a bit longer.

[Paul E]

Nice and slow with plenty of lube

[jwalker]

And if yerv got the skill, resharpen the drill to around 80º, it'll transform its cutting ability. If you're using a powerful hand drill, take care as the drill penetrates because it is likely to spiral in and wrench you wrists. The technique is to hold off the pressure for the last part of the cut.

[bedajim]

If your drilling above the tubes cover them too

[jyasaki]

I prefer to use cutting oil as a lubricant for metal work. A can (or bottle) runs about $6, and lasts quite a while. The difference in cut/drill quality is reasonably notable. Stuff is usually sold as "thread cutting oil", "cutting fluid", or somesuch. I use it on drill bits, hacksaws, pretty much any kind of metal cutting. A locksmith once told me its one of the better products for lubricating a sticking front door lock (though I have no idea why.)

jky

[m chappelow]

a local engineering firm that uses loads of stainless steel in the manifacture of mortury equipment,recons that for drilling in plate stainless a few drops diesel fuel will make it drill as good as some of the cutting oils ,it he who says its sometimes easier to punch a hole through if its thin enough .

[cgf10]

I had no idea hole drilling answers would get beyond one page, thanks for all the advice, particularly the centre punch idea as I'd anticipated a slippery start to drilling and was contemplating using some adhesive tap over the drill area until I saw this idea. Drilling tomorrow, I feel prepared and confident !

[bedajim]

Originally Posted by jyasaki

I prefer to use cutting oil as a lubricant for metal work. A can (or bottle) runs about $6, and lasts quite a while. The difference in cut/drill quality is reasonably notable. Stuff is usually sold as "thread cutting oil", "cutting fluid", or somesuch. I use it on drill bits, hacksaws, pretty much any kind of metal cutting. A locksmith once told me its one of the better products for lubricating a sticking front door lock (though I have no idea why.)

jky

Yep but then you have to clean it up, if it's just a couple of holes on an aframe mounted on the rib, water is far easier and minimum mess

Jim

[Bigmuz7]

Originally Posted by cgf10

I had no idea hole drilling answers would get beyond one page,

But this is Ribnet We can spin out some total mince for ages and ofcourse hole drilling is a specialist subject ... 2 pages and some usual contributors havent even warmed up yet ?