Drilling holes in stainless

[h22lude]

I have a new pot for a e-biab system. I need to drill a few holes. I did one small one in the lid for the recirculating arm. I'm doing the bigger one for the element. I had a cheapo step bit that was working but after about 1" it wouldn't drill anymore. Returned that and bought a Greenlee one. It seems to be doing ok but not as good as I was hoping. My drill gets stuck and there are a ton of burrs.

I am using a cordless 9.6V Dewalt. It may be under powered but I figured it would still work. Do i need to get a corded drill for this?

What is the best bit to make the hole smooth?

 

[stpug]

Slow drilling speed, firm downward pressure, lots of cutting oil reapplied while drilling. That's the best method. You can clean up the burred edges after you've drilled your hole with a dremel sanding wheel, or hit the hole from the opposite side since most stepbits have natural deburring capability.

You definitely need a drill that can do the job (i.e. not bog down and stop the motor).

 

[MrNatural]

Slow drilling speed, firm downward pressure, lots of cutting oil reapplied while drilling. That's the best method. You can clean up the burred edges after you've drilled your hole with a dremel sanding wheel, or hit the hole from the opposite side since most stepbits have natural deburring capability.

You definitely need a drill that can do the job (i.e. not bog down and stop the motor).

^^^^^this^^^^^^

 

[h22lude]

Maybe I'm going to fast and push down too hard. I did see a lot of people say WD40 was ok so I have been using that. Is that ok to use?

How is this drill? I don't want to buy anything nice. I'll use this drill just for this and my grain mill.

http://www.lowes.com/pd_242197-79992-DR260B_1z0wcix+2z8vl__?productId=3339842&Ns=p_product_qty_sales_dollar|1&pl=1&currentURL=%3FNs%3Dp_product_qty_sales_dollar%7C1%26page%3D1&facetInfo=$15%20-%20$25

 

[h22lude]

Target across the street from me had it so I bought it. Worked like a charm. It was definitely my old under powered drill.

 

[WayFrae]

Get a knockout punch. I used the one from Harbor Freight to punch the holes in my kettle for the spigot and it worked like a dream. I am sure it isn't as nice as the Greenlee ones but you can get a whole set for half the price of one Greenlee punch. These punches just require you to drill a smaller hole for the punch shaft to go through and then it punches a perfect hole without any burrs.

 

[dmcman73]

If you drill to fast and the bit heats up, it will heat op the stainless steel and harden the metal making it difficult to drill and it will destroy your bit. Put the drill on a slow speed with high torque and use lots of cutting oil. If it's too difficult you may have hardened the stainless and your next best option is to use a knock out punch. Make sure you use the conduit punches.

 

[passedpawn]

Get a knockout punch. I used the one from Harbor Freight to punch the holes in my kettle for the spigot and it worked like a dream. I am sure it isn't as nice as the Greenlee ones but you can get a whole set for half the price of one Greenlee punch. These punches just require you to drill a smaller hole for the punch shaft to go through and then it punches a perfect hole without any burrs.

^^ take it from someone who's drilled about 10 1/2" holes and several 1.25" holes, this guy is right. Step bits suck. Get a punch set.

 

[MaxStout]

^^ take it from someone who's drilled about 10 1/2" holes and several 1.25" holes, this guy is right. Step bits suck. Get a punch set.

This.

Step bits work OK in a drill press, at greatly reduced speeds (~200-300RPM), and with lots of oil. Drill 1 step, add some more oil, drill the next step, add oil...

I see a punch set in my future. Any excuse to buy another tool.

 

[h22lude]

The step bit with the new cheap drill worked really well. The knockout punch is a good idea. Though I needed a new drill anyway and already had the step bit bought.

 

[Stealthcruiser]

WD-40 as a drill lube, no...........Use some oil , cutting or tapping oil preferred, motor oil second.

 

[Wavery]

The step bit with the new cheap drill worked really well. The knockout punch is a good idea. Though I needed a new drill anyway and already had the step bit bought.

The key to drilling S/S is using the correct cutting oil. Never use WD40......

You want to use "Rapid Tap" cutting fluid:
http://www.amazon.com/RELTON-04Z-NRT-Rapid-Cutting-Drilling/dp/B000LGCF6A/ref=sr_1_3?ie=UTF8&qid=1422395117&sr=8-3&keywords=rapid+tap

As stated previously, use a slow speed and steady pressure. You will think you are drilling through wood.

Never back off when drilling stainless. If you do, the steel will cool rapidly and harden (as stated previously) but the key is using the correct cutting fluid. Have someone put one drop per second in the hole as the drill bit cuts.

I've drilled through 1/2" thick 316 S/S using this fluid. I've cut as many as 12 holes with 1 drill bit.

 

[Zepth]

I had great success multiple times using plain old water as my cutting lubricant and coolant. Slow steady continuous spray from a spray bottle did the trick and I didn't need to worry about getting something nasty into my brew pot. A good and proper cleaning should be done either way, but I am lazy and the first to admit it.

Nobody seems to have problems with the pilot hole. My step bit just couldn't get the job done. A quality drill bit (in my case cobalt) will eat right through that stainless like it's wood. My cheapest step bit I could find did swell after that with a 12v Rigid Lithium. Deceptively powerful little guy. Wasn't too happy but for a couple holes it worked.

Of course if one were to harden their pot it would be possible to temper it. Not fun or easy, and best avoided but it would make it drillable again.