# Stainless - Who Makes The Best Drill Bits And Taps On The Planet?



## coolidge (Oct 19, 2015)

I'm riled up so price is no object. I used cobalt drill bits on a stainless project and HSS taps. Man it was kind of ugly it sounded like the stainless was cracking and snapping both during drilling and tapping. I'm used to stainless being kind of gummy I don't know maybe the square tubing was work hardened or something. I shattered a tap and a drill bit even though I was using tap magic. The bits got HOT.


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## Doubleeboy (Oct 19, 2015)

Use some TCE with the the tapping fluid, cuts like butter.  35 years ago Tapmagic came with TCE in it, it was the real deal for tapping, threading and getting an awesome finish on a finishing cut.   You can still get it from Scientific Supply houses, 100 per cent.  Just add a few drops to an ounce or so of your favorite cutting fluid and you gots the stuff.
michael


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## Tony Wells (Oct 19, 2015)

When I have tough material to drill, I turn to Guhring first.


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## JimDawson (Oct 20, 2015)

316 SS?  Slow speed, with a fair amount of feed.  Feed like you really mean it, if you let the tool rub it will work harden.  Also good carbide bits work pretty well.  Sometimes I even use concrete bits.  I actually have a 0.201 concrete bit for 1/4-20 tap size.


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## Ulma Doctor (Oct 20, 2015)

I like 2 flute gun taps, 
Besley, Guhring, & OSG all make excellent quality taps

I like cobalt drills for stainless, lots of bacon grease/mineral oil- 50/50 for drilling and tapping
hard feed, low speed


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## JimDawson (Oct 20, 2015)

Ulma Doctor said:


> I like cobalt drills for stainless, lots of bacon grease/mineral oil- 50/50 for drilling and tapping
> hard feed, low speed



Ahhhh.  Another good reason to eat more bacon.


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## TOOLMASTER (Oct 20, 2015)

i have used nozzle dip for the last 30 years


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## coolidge (Oct 20, 2015)

Thanks for the input I'm mulling over an order...


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## Holescreek (Oct 20, 2015)

I've been using the same Cleveland HSS drill bit sets I was first given in 1981.  Yes, a few bits have been replaced multiple times but  from getting to short.  They've cut every unhardened material I've put them on. Sounds to me like you're running too many RPM's.


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## coolidge (Oct 20, 2015)

400 to 600 rpms drilling, the tap shattered tapping by hand.


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## planeflyer21 (Oct 20, 2015)

Maybe I missed it but what size tap?


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## JimDawson (Oct 20, 2015)

Without knowing what size hole you were drilling it's a bit hard the determine if that is fast.  I think it would be too fast in 316 for a 1/4 inch bit.  I also normally use a 50-65% tap drill in SS, rather than a 75% tap drill.  Spiral point or spiral flute is best in SS.


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## coolidge (Oct 20, 2015)

The tap that snapped was 1/4-20 the drill bit was .125 I was just drilling a pilot hole for a larger bit.


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## coolidge (Oct 20, 2015)

I ordered a set of two flute M.A. Ford Hi-Roc drills today, designed for drilling hardened steels, stainless, nickel alloys, Ti, etc.


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## JimDawson (Oct 21, 2015)

Those are pretty cool.  Do you have spiral point taps?


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## coolidge (Oct 21, 2015)

Jim taps are next on my list, still researching. I have an assortment of regular HSS taps on hand is all, some low grade china some made in USA, neither liked this stainless.


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## Tony Wells (Oct 21, 2015)

Those carbide drills are excellent, but be sure and keep the chips clear. They don't have the spiral of  twist drill to help evacuate the chips. I use a steady air blast and peck those. Also, on breakout, the corners are delicate. I think once you get used to them, you will like them. I have a few special jobs I use that style on. Love them for it.


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## JimDawson (Oct 21, 2015)

Hertell (from Enco) makes good taps, I also like the ones from Fastenall.  I only buy spiral point or spiral flute taps, unless I need to get a junker from the local hardware store.  Spiral point is what I use the most for general work , but spiral flute works good in stainless

Spiral flute



Spiral point


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## coolidge (Oct 21, 2015)

Jim do you drive those spiral flute through in a single pass? Does anyone have any thoughts on thread forming taps?


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## JimDawson (Oct 21, 2015)

Normally yes.  They are really designed for power tapping in blind holes.  The chip is pulled out of the hole.






There is nothing wrong with thread forming taps.  Not sure how they work in SS.  I have a few 1/4-20 but I have never used them.  Less prone to breakage than cutting taps.


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## planeflyer21 (Oct 21, 2015)

+1 on the spiral flute taps.  We ran those (1/4-20) in hard 17-4 castings.  We also ran a 2-56 in the same part, could only get maybe 5 holes before they snapped.

I still hate those valve covers.


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## Wreck™Wreck (Oct 23, 2015)

coolidge said:


> The tap that snapped was 1/4-20 the drill bit was .125 I was just drilling a pilot hole for a larger bit.


Don't drill a pilot hole, not surprised that you were having problems doing it that way.
Spot drill if needed then drill to size in one shot. Above all try to maintain a continuous chip either by hand or power feed.


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## samthedog (Oct 24, 2015)

Guhring, Titex, SKF, Dormer and Volkel are all decent brands. Just make sure that the machine or spiral taps are rated for stainless since there are different taps for different materials. Stainless is pretty tough on taps and dies so make sure you use decent quality. Just try to do your drilling and tapping with single passes since the work hardening will cause you grief.

Once you use spiral or machine taps you won't go back to regular hand taps. 

Paul.


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## coolidge (Oct 24, 2015)

Inbound - 2 sets of Guhring Cobalt spiral flute taps, 3 flute for steel and 2 flute for aluminum in 8-32, 10-24, 1/4-20, 5/16-18, and 3/8-16. While I had the MSC discount maxed out I ordered a couple of Collis end mill holders to try out.


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## coolidge (Oct 24, 2015)

The M.A. Ford Hi-Roc solid carbide drill bits arrived. Applications include steels, hardened steels (35-65Rc), stainless steels, special alloys, and non-ferrous. These are NOT for use on cast iron.

Here's the 1/2 bit...quoting the sergeant in in Alien 2, we have come to conquer and we are going to get some! Get in the Kurt stainless its time to die! (mad scientist type laugh)


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## Tony Wells (Oct 24, 2015)

As you know, speeds and feeds are critical with carbide, especially so with stainless.


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## Doubleeboy (Oct 24, 2015)

Endmill Holders..... For when you absolutely, positively, have to have more runout!!    

cheers
michael


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## coolidge (Oct 24, 2015)

Endmill Holders...For when you need brute grip while roughing and hogging. Collets for when you are taking light cuts like Michael.


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## Wreck™Wreck (Oct 24, 2015)

You are planning on using carbide die sinking drills in a wobbly knee mill?
Good choice of tools as they are pretty much bullet proof.
Please let everyone know how it works out for you.


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## EmilioG (Dec 28, 2015)

I like and use C-L, OSG and Guhring is my fav for all drills and taps.  MA Ford and others are in my box too. I have a few Emuge taps too, very nice Muti-Taps.


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## kingmt01 (Dec 30, 2015)

So how did they work?

Sounds like I always approached SS wrong. If making a small hole I start with a 1/8 drill & work up in 1/8ths until I'm at size & cooling with water. I never could drop the stuff in one pass or with using oil. If it is a big hole I'll use a hole saw & cut really slow flooding it with water. Speed is what always killed me. Once work hardened I always over cut the hole or burnt it & then figured out what to do with the extra hole. I never tried to tap any.


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## EmilioG (Apr 22, 2017)

Guhring and Emuge are my two favs, with Widia and OSG. Emuge makes a great MulTiTap for most materials.
The Guhring ticn for aluminum are awesome. I usually buy the cobalt bright taps for all materials., yellow ring.
Guhring, hands down.


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