Cutting Grease

[k1100t]

I pretty much have everything I need to start building my new stainless three pot system. One thing I'm not sure about though, is what to use as cutting grease, when drilling the pilot holes for the Q.Max hole punches. Just wondering if anyone has any recommendations...? I have a couple of different types of bike chain oil and some copper grease kicking around, other than that, I'll need to buy something (unless you can use coconut oil or similar). So would one of those do, or do I need to buy some 3-in-1, or WD-40 cutting oil...?

Thanks,

[Haydnexport]

Anything will do really , it's more for keeping the drill bit cool , use whatever is near , wd40, spray grease, fairy liquid or as I used last night my starsan sprayer

[jaroporter]

use some cooking oil or something foodsafe. that way it's less worry trying to clean all the shıt off afterwards. i'd go for something thicker like rapeseed or olive oil than coconut, but whatever you got to hand. if it's getting hot, stop, clean, and reapply

[Dads_Ale]

WD40 (recommended by Bridgewater Brewing)

[Kev888]

Rocol cutting fluid is good, but probably too costly for one small job, alternatively I'd use WD40.

Whatever you choose, apply plenty of pressure (within reason, don't endanger the bit or pot) and use a very slow drill speed to give the bit chance to cut. If it rubs instead of cuts then even with cutting fluid it will harden the stainless further than it is already.

[chris246810]

And don't forget to repassivate your pots after cutting

[Fil]

ive used wd40, but recently i needed to drill thru 2mm plate SS and i bought a toothpaste sized tube of cutting grease. a wee knob stayed in place round the 4mm jobber hss bit i used for the initial hole which slipped thru so much easier than the wd40 cooled wafer thin thermopot lid skin..

so invest £3-£4 in a small tube of cutting grease, google has failed me for a product id, if your stuck and cover the cost of the stamps pm me i can send you some from the tube i have.. you need a pea sized dollop on each drill spot..

[BenB]

Cutting oil is used to keep the bit cool. The amount / type required depends on the duration of drilling. I find when using 100% Cobalt bits the drilling is now so quick the bit doesn't have chance to get hot. I just squirt a bit of cutting oil onto the bit half way through. What makes all the difference when drilling is to use a center punch to divot the metal. I tend to just use a panel pin held in some pliars and a bit hammer. Even if you can't see the divot it makes such a dramatic difference- it used to take 20 minutes + to drill a hole, now by using a centre punch it takes less than a minute! The divot stops the bit from wandering and presents a flat (drillable) surface to the bit instead of a convex surface that curves away from the cutting surface of the bit.

It's like night and day drilling with and without a centre punched hole. And as said you don't need to make a visible divot like if you're drilling ali sheet.

Important thing- if you find the drill bit is getting hot stop drilling. It's really easy to work harden stainless whilst drilling and if you do it makes the stainless ridiculously hard and drilling almost stops.

[BenB]

If you're drilling thick stainless a good trick is to use blu-tak / plasticine etc to make a ring and then stick that around the hole site to make a well. It'll keep the cutting oil in situ even on a convex surface (assuming you're drilling downwards).

[Kev888]

I find when using 100% Cobalt bits the drilling is now so quick the bit doesn't have chance to get hot.

Where on earth can you get 100% cobalt bits?

[mozza]

I find when using 100% Cobalt bits the drilling is now so quick the bit doesn't have chance to get hot.

Where on earth can you get 100% cobalt bits?

got mine from toolstation for about £2 each

[Wonkydonkey]

Would that be 100% colbalt coated :wink

Edit; looking at the pro cobalt drill bits, it says always use a cutting coolent /grease
http://www.toolstation.com/shop/p75018

[Kev888]

Ha, its always a possibility.

The ToolStation ones are decent bits and great value, I buy them too, but they're only 5% cobalt.