# drilling stainless steel



## goose134 (Nov 12, 2007)

I've got a project that requires me to drill a lot of holes in stainless plates. The hole saws are holding up nicely, but my drill bits are really getting burned up. I'm starting small and gradually working up through the sizes to 3/8" but the larger sizes still seem to suffer the brunt. Any tips or recommendations on brands or types of bits for stainless?


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## randomkiller (Sep 28, 2007)

I go to Grainger and get the solid cobalt ones for stainless.


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## TOOL_5150 (Aug 27, 2007)

randomkiller said:


> I go to Grainger and get the solid cobalt ones for stainless.


And oil! :thumbsup:

~Matt


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## Southeast Power (Jan 18, 2009)

*Tap Magic*










Tap Magic.............:thumbsup:


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## paul d. (Jul 13, 2008)

yep. GOOD drill bits. and tap majic, or cutting oil. AND low RPM's amazing how many guys cant drill a hole in stainless. or cant drill a hole at all. gosh i'm gettin grumpy in my old age.


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## nick (Feb 14, 2008)

*Cutting stainless cans*

Well heres some more electrician to electrician stories !! cutting stainless steel in a panel can or disconnect .http://i611.photobucket.com/albums/tt195/stringking/P1010048_01.jpg

[One] method buy a lenox hole saw for stainless steel with a stainless steel bit the bit has two tip heads one to poke thur then the other cuts the 1/4 bit hole .

[Two] method cut with stainless hole saw and knock out with stainless steel greenlee knock out set . dont use a regular knock out set it will brake you cutting bolt .


[Three] old method ya know when you dont have the above stuff ! in a pinch no money !! or the boss forgot to order a hole saw for stainless !! Sugar and oil pour sugar and oil on stainless use a regular hole saw slow speed . next go in reverse than go in forward go in reverse than go in forward with your drill motor at very slow speed keep level and straight pressure on hole saw it will go thur ! the sugar helps with the heat that turns the stainless blue in color the oil lubes the drill . BUT just get a stainless cutter thats best ! take care be safe


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## MDShunk (Jan 7, 2007)

Slow and a lot of pressure. You drill full speed and you'll burn all your stuff blue in nothing flat.


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## paul d. (Jul 13, 2008)

what marc sad x 2


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## MDShunk (Jan 7, 2007)

When I first started doing electrical work, one of my first jobs was in a new sewer plant. Almost everything was stainless steel. I think my main job for months was drilling, tapping, and knocking out holes of all sorts in stainless steel. That job sucked. Good for the new guy. Drill a #7 hole for a 1/4-20 tap fast, and you'd get one hole out of that bit. Drill it slow and with a lot of pressure, and you could do 50 holes. 

Tap Magic is good stuff, but careful if you use it on milling machine and lathe operations. That stuff turns to thick varnish if it builds up in the ways of the machine. Just a side note.


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## nick (Feb 14, 2008)

*Method four*

Well heres the storie had a helper forgot to cap the wires laying on top of a stainless steel counter top just a no. 10 wire 120 volt hot 30 amp circuit it blew a 1/4 hole straight thur the stainless steel top had a copper looking effect around the hole .
I was going to put this down as method four but dont do this !!!

The stainless fab guys had to dress it up a little ya could not tell when they got done a good stainless welder fab guy can save the day . best to yas


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## mattsilkwood (Sep 21, 2008)

just like everybody else said good sharp bit and low rpm, cutting oil is a good idea but not neccesary. fastenal has this stuff, its about the consistency of honey that works great, i cant remember the name right off hand.

my method has always been drill a 1/4" hole first, then go to a unibit,then ko whatever size you need. piece of cake.


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## randomkiller (Sep 28, 2007)

TOOL_5150 said:


> And oil! :thumbsup:
> 
> ~Matt


 
Very true.


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## azsly1 (Nov 12, 2008)

mattsilkwood said:


> just like everybody else said good sharp bit and low rpm, cutting oil is a good idea but not neccesary. fastenal has this stuff, its about the consistency of honey that works great, i cant remember the name right off hand.
> 
> my method has always been drill a 1/4" hole first, then go to a unibit,then ko whatever size you need. piece of cake.



i know the stuff your talking about from fastenal. the stuff i have i cant remember the name right now but the other product that has the same thick consistency is called 'Mike-o-cut' i think...

my local fastenal doesnt stock the mike-o-cut, but they stock the other stuff. usually in small bottles.

anchor lube also works well, its a water based lube that cleans up real nice after your done drilling. no sloppy mess of oil all over the place. you need a little more of it though...


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## MDShunk (Jan 7, 2007)

I've been working through the same gallon bottle of excalator lube that I use for tapping and drilling. I think I'll have that bottle for the rest of my life. The nice thing about escalator lube is, not only does it work well for tapping and drilling, it doesn't make a mess or stain your clothes.


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## Adam12 (May 28, 2008)

I have even heard of using milk as a lubricant.


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## goose134 (Nov 12, 2007)

Good tips. I may invest in the bits, and I have been running slow. I should have probably doing it with oil, and I will start on the next batch. Thanks again.


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## Johnpaul (Oct 2, 2008)

The oil is not serving as a lubricant but as a coolant. Water would work as well. Stainless steel when heated will self-temper and get harder. You minimize the heat buildup by using a lower RPM, more pressure so that the cutting edge is cutting rather than spinning and adding heat from friction, and if practical using a coolant. The RPM charts for stainless hole cutters will often specify a RPM that is half that of the lowest RPM provided on a hand drill. The best solution is to get a speed reducer for the drill chuck that will reduce the RPM at the drill head by 50% or more. With hole saws there is a big jump in performance as you go from a bi-metal or high speed steel hole saw to a carbide bi-metal, to a tungsten carbide insert hole cutter, often by a factor of 50 in terms of the time to cut a hole and the number of holes per hole cutter. The cheap HSS bi-metal hole saws are always going to be the most expensive hole cutting tool on a holes per dollar basis for any material.


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## BuzzKill (Oct 27, 2008)

Johnpaul said:


> The oil is not serving as a lubricant but as a coolant. Water would work as well. Stainless steel when heated will self-temper and get harder. You minimize the heat buildup by using a lower RPM, more pressure so that the cutting edge is cutting rather than spinning and adding heat from friction, and if practical using a coolant. The RPM charts for stainless hole cutters will often specify a RPM that is half that of the lowest RPM provided on a hand drill. The best solution is to get a speed reducer for the drill chuck that will reduce the RPM at the drill head by 50% or more. With hole saws there is a big jump in performance as you go from a bi-metal or high speed steel hole saw to a carbide bi-metal, to a tungsten carbide insert hole cutter, often by a factor of 50 in terms of the time to cut a hole and the number of holes per hole cutter. The cheap HSS bi-metal hole saws are always going to be the most expensive hole cutting tool on a holes per dollar basis for any material.


I think someone on here mentioned vinegar too as a lube?


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## Frasbee (Apr 7, 2008)

The electricians I worked with disputed using low RPM's. They told me to hit it fast and hard to save bit life.

A bosch manual I had read, said to use a low gear speed for metal, good to hear people supporting this.


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## jwjrw (Jan 14, 2010)

BuzzKill said:


> I think someone on here mentioned vinegar too as a lube?


 

Yep they did. I have not tried it yet. But I am going to next time I have some stainless to go thru. Last time I had to do it I bought some carbide tip hole saws.They are awesome! Expensive but work great.


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## MDShunk (Jan 7, 2007)

jwjrw said:


> Yep they did. I have not tried it yet. But I am going to next time I have some stainless to go thru. Last time I had to do it I bought some carbide tip hole saws.They are awesome! Expensive but work great.


They are great. The first one I got I actually bought accidentally, since it was in a box. When I opened it up on the job and realized what I had, the first thing I did was look at my counter slip to see what I paid. I forget what it was, but it wasn't too hateful. Worked like a dream. The thing was only about 3/4" deep, so it wouldn't be good for much other than sawing knockouts.


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## BuzzKill (Oct 27, 2008)

speaking of hole saw, how do those shallow all steel type with only a few blades on them work, as opposed to the normal couple inch, allot of teeth variety?


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## MDShunk (Jan 7, 2007)

BuzzKill said:


> speaking of hole saw, how do those shallow all steel type with only a few blades on them work, as opposed to the normal couple inch, allot of teeth variety?


Those are the one's I was just talking about above. They're really nice. They have a spring inside that ejects the slug pretty well also. The main drawback might be that they take a special pilot bit, but the way they're made, you should break far fewer pilot bits versus the traditional design. Your existing mandrels will still work with these new style hole saws.


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## jwjrw (Jan 14, 2010)

MDShunk said:


> They are great. The first one I got I actually bought accidentally, since it was in a box. When I opened it up on the job and realized what I had, the first thing I did was look at my counter slip to see what I paid. I forget what it was, but it wasn't too hateful. Worked like a dream. The thing was only about 3/4" deep, so it wouldn't be good for much other than sawing knockouts.


 

I think I paid like $130.00 FOR A 1/2. 3/4, and 1" .
They were worth every penny.:thumbup:


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## MDShunk (Jan 7, 2007)

jwjrw said:


> I think I paid like $130.00 FOR A 1/2. 3/4, and 1" .
> They were worth every penny.:thumbup:


Yeah, I'm thinking the single one I got was around 40-45 dollars. I forget, really. That's probably what I'm going to stat buying as I need to replace. I don't saw too many knockouts, but from time to time they're handy. I mostly use hole saws for stuff other than boxes and cabinets, so I need the depth of the traditional design.


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## jwjrw (Jan 14, 2010)

MDShunk said:


> Yeah, I'm thinking the single one I got was around 40-45 dollars. I forget, really. That's probably what I'm going to stat buying as I need to replace. I don't saw too many knockouts, but from time to time they're handy. I mostly use hole saws for stuff other than boxes and cabinets, so I need the depth of the traditional design.


 

Very little of our work has stainless steel. I usally use my hydrallic KO on normal panels etc. On the stainless I tried a regular hole saw then a uni-bit. No go. I used a ko and wrenches till I found the carbon hole saws. It works but not sure if it is the best way to make holes in stainless. Haven't seen how others do it.


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## BuzzKill (Oct 27, 2008)

jwjrw said:


> I think I paid like $130.00 FOR A 1/2. 3/4, and 1" .
> They were worth every penny.:thumbup:


yeah that's them!
one day when I need them for a good job I'll buy some...I must refrain from buying tools that I don't need right away!


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## jwjrw (Jan 14, 2010)

BuzzKill said:


> yeah that's them!
> one day when I need them for a good job I'll buy some...I must refrain from buying tools that I don't need right away!


 
I dont think I could of done those 2 jobs without them. Haven't used them since either. But I got em if I do!


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## BuzzKill (Oct 27, 2008)

jwjrw said:


> I dont think I could of done those 2 jobs without them. Haven't used them since either. But I got em if I do!


That's when it's justified for me to buy: when the job demands it and it pays for itself.


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## Johnpaul (Oct 2, 2008)

I had a recent job where I needed to drill large holes through 16 gauge stainless with a foam backing for insulation. Took 3x as long as normal because the Styrofoam acted as an insulator and kept the heat in the stainless sheet. High speed equals high heat and this causes the stainless to "work harden" as you drill. All drill and hole cutter manufacturers specify a different optimum drill speed for different materials, and Champion for example with its TCT hole cutters for metal recommends for a 2" hole in steel a RPM of 200-500 but for stainless steel a RPM of 120-225. Evergreen Tool coverts drills for use on stainless steel by adding a speed reducer so the hole cutter is moving at 250 RPMs or less. You want to use the lowest setting of your drill and apply enough pressure with a drill bit to spin off a continuous piece of metal. If the bit is not capable of doing this then get a better drill bit, i.e. cobalt. Not rocket science but it does pay to RTFM or at least the outside of the box.


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## Lone Crapshooter (Nov 8, 2008)

Low speed with cutting oil or a cutting fluid , DO DOT CENTER PUNCH it will work harden the stainless use a split center or center less bit Grainger or Fastenal has then as a stock item they do not require center punching. 
Do not let the bit spin in the hole without pressure that also will cause work hardening. One misconception is that all oil will work for drilling and tapping. Not true . Lubricating oil will lubricate it will actually make drilling and tapping slower because it is reducing friction and not letting the tools cut.


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## oldtimer (Jun 10, 2010)

Lone Crapshooter said:


> Low speed with cutting oil or a cutting fluid , DO DOT CENTER PUNCH it will work harden the stainless use a split center or center less bit Grainger or Fastenal has then as a stock item they do not require center punching.
> Do not let the bit spin in the hole without pressure that also will cause work hardening. One misconception is that all oil will work for drilling and tapping. Not true . Lubricating oil will lubricate it will actually make drilling and tapping slower because it is reducing friction and not letting the tools cut.


 They make cutting oil for stainless steel, it's expensive but it saves burning bits.

Machine shops use it. I can't remember who makes it, maybe 3M.

O M G ! Isn't that who makes Scotchkote. :laughing::laughing: B4T??


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## RIVETER (Sep 26, 2009)

This thread seems to be very old but with renewed interest. I have drilled a lot of stainless holes too. I stuffed the hole saw with a rag and soaked the rag with cutting oil. As it rotates it slings the oil to the blade and the blade still did not seem dull after many, many holes.


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## s.kelly (Mar 20, 2009)

Off topic a bit, but how about Nick from FL. His posts were always hard to read, but usually good. Seemed to be knowledgable, but I do not see posts from him anymore.


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## Johnpaul (Oct 2, 2008)

BuzzKill said:


> speaking of hole saw, how do those shallow all steel type with only a few blades on them work, as opposed to the normal couple inch, allot of teeth variety?


Most work much better than a bi-metal hole saw with lots of little teeth. The few large teeth are a much harder form of tungsten carbide and the good quality ones have the teeth dovetailed into the side of the hole cutter. 

Most use a 6mm pilot bit and so a standard 1/4" (6.35mm) pilot will not work, but then the pilot bit needs to be shorter as well. 

The quality and performance varies by a lot more than one might think. All the ones current sold in the USA are what is know as "Japanese quality" and this is the the lowest quality made. There is a medium grade sold only in Asia and a top grade "European" type sold in Asia and Europe. The Champion and Ideal are the Japanese quality type and overpriced. I am waiting for the new Blue Boar ones to come out next month as these will have a 5/8-18 thread mount so I can use them on a regular drill arbor and they will be less expensive than the ones from Champion and Ideal from the preliminary price list I saw.


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## Innovative (Jan 26, 2010)

The Ideal TKO hole saws work great.... have been using a set for a little over a year now.... hundreds of holes drilled and the bits are still very sharp. The set runs about 230.00, but well worth it. I usually use the Greenlee cutting lube and have had no problems.

http://www.idealindustries.com/prodDetail.do?prodId=36-314&div=3&l1=saws_drill_bits&l1b=tko


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## sparky970 (Mar 19, 2008)

goose134 said:


> I've got a project that requires me to drill a lot of holes in stainless plates. The hole saws are holding up nicely, but my drill bits are really getting burned up. I'm starting small and gradually working up through the sizes to 3/8" but the larger sizes still seem to suffer the brunt. Any tips or recommendations on brands or types of bits for stainless?


Drill a 1/8" hole in the cap of a water bottle and fill with water.


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## John Valdes (May 17, 2007)

The first time I drilled stainless it was when I was a young green hand. I could not find some plates to fit NEMA twist locks and the guy behind the counter knowing I didn't know squat sold me some stainless blanks. Like 20 or so. It took me forever to drill out the plates with a standard hole saw. When the contractor heard I bought stainless he almost had fit until he found out the job got finished that day and we did not have to wait on the right plates.
I was all alone that day and was left alone much more after that.


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## Toronto Sparky (Apr 12, 2009)

Drilling compound for stainless steel works well even with regular hole saws. Most wholesalers have it.


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## Schultz134 (Jul 25, 2010)

I was always told either really slow or hard and fast. Everybody knows to go slow to prevent heat build-up, but the same idea was for the hard and fast. If you push hard and go fast, it eats through the metal before it has a chance to heat up. Both have worked fine for me. I don't drill stainless every day though so I can't say much for bit or hole saw life with these methods.


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## MDShunk (Jan 7, 2007)

Schultz134 said:


> I was always told either really slow or hard and fast. Everybody knows to go slow to prevent heat build-up, but the same idea was for the hard and fast. If you push hard and go fast, it eats through the metal before it has a chance to heat up. Both have worked fine for me. I don't drill stainless every day though so I can't say much for bit or hole saw life with these methods.


Hard and fast works well in a milling machine or drill press, but hard to pull off with a hand drill without breaking bits. The most common thing I have to drill in stainless is #7 drill holes for a 1/4-20 tap, and I'd be breaking bits left and right if I tried to press really hard.


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## ohiosparky99 (Nov 12, 2009)

depending where you need the holes you could get a whitley hydralic punch, had to have approximately 20 3/8 holes in stainless angle for brackets, with a punch you could do it in less than 2 minutes, with a bit and oil it took 6 hrs, punch the starter hole you need than knock out with ss knock outs.


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