Cobalt vs Titanium

[tomsmith]

Hello,

Let me start by saying I appreciate that everyone has different opinions and use cases. I'm just posting my experience as a very junior home hobbyist who is starting metal work

I bought a variable speed (750rpm is the slowest setting which I know is a bit too fast for metal drilling but anyway..) drill press and have been using titanium coated drill bits to drill into 3/16" or 1/4" steel. I always found I have to use a lot of WD40 to keep the bit cool and that I can drill around 10 holes in 3/16" steel before I notice the bit is dull. I know this because it heats up much quicker and takes longer to drill through.

I've been reading through the many, many threads and posts on Cobalt vs Titanium coated and figured I'd invest in a cobalt bit set from Canadian Tire (link).

After using the cobalt bits for a couple of weeks now, I can say that I find them to be much better performing when used for drilling through mild steel. I've drilled maybe 30-35 holes in total using the 3/8" bit and it feels as sharp as day 1. I don't have to use much WD40 to keep the bit cool. I can drill maybe 3 holes and the bit is still comfortable enough to hold, couldn't do that with the titanium bit and it cuts cleaner and quicker.

When I was using the titanium coated bits, I would get little bits of metal flying around but with the cobalt bit, I get nice long spirals if I get the feed rate just right - I don't know why, but I love seeing the long spirals of steel when drilling

I have a drill doctor and use it pretty reguarly to keep my HSS bits sharp but, as I mentioned, not had to use it with the cobalt bits yet.

I hope this is helpful for those like me who tinker with metal. If you expect to be drilling into steel, try a cobalt bit - made a world of difference for me.

 

[ozyborn]

Good bits are worth their weight in gold, or cobalt in this case.

I only buy cobalts now. I hate sharpening the bits....I also hate them when they go dull.

 

[Gtamazing]

Those titanium drills from Canadian Tire are junk(I have the full index).

 

[SINISTER]

I have a piece by piece set built with Cleveland cobalt drill bits. They have served me best IMHO, compared to Cman, HF, and Irwins. I still have a multi purpose set of black oxide that I use for wood.

They really are worth their weight in gold. Not to say I haven't smoked my fair share of cobalt bits in high strength steel, but they are the only type of bit that can get that job done.

 

[oldtools]

I don't think WD40 is a cutting fluid. I never used it that way.

 

[Outlawmws]

I don't think WD40 is a cutting fluid. I never used it that way.

It's not bad for aluminum. Not too good for other materials.

Keep in mind, it's predominantly kerosene

 

[Trucky]

Do yourself a favor and buy some HSS drills if you're doing metalwork.

I recommend Norseman because they're not too expensive and get the job done well.

http://www.fairburyfastener.com/norseman.htm

I really don't like your drill press, but I guess you're going to have to deal with that. And I'd also like to suggest getting some real cutting fluid. Do a little google searching and you'll find a lot of stuff that is pretty cheap, and effective to boot. Just a suggestion, I don't want your shiny new drills going bad on you too quickly. Also, a good means to sharpen them wouldn't hurt either.

EDIT: Initially skimmed your post, re-read it again. Missed the part about the drill doctor, forgive me

I've used cobalt and "titanium" bits before as well but for the kind of work I need to go I usually have to use HSS as a minimum or carbide if available. Glad to see you had a positive experience with them.

 

[Schurkey]

It's probably not fair to compare Made in China "titanium" bits to Made in America HSS. An micro-thin but expensive coating on top of crappy steel is no substitute for proper steel to begin with.

I am no fan of "split point" bits; the thick webs may be strong but they don't drill worth squat.

If you're using a Drill Doctor, you should learn to sharpen bits on a ~6" bench grinder. The company I worked for had a Drill Doctor; what didn't go through the Drill Doctor went out to a subcontracted sharpening service.

When the resharpened bits came back to me, I took them to a bench grinder and fixed the screwups. They'd work much better with proper back-cut and relief.

I learned very quickly to NOT turn in dull bits. It was just easier to resharpen all my bits than to get poorly-resharpened bits from the company supplies.

 

[JASTECH]

Other then real cutting fluid instead of Water Displaser 40, your Carbides will last. The next step up might be CryoBits. Now what about useing "Rheostat Pedal", this will slow it down but will cost you power. If you have a induction motor it won't work. Maybe best to weld another pully on yours?

 

[IndyGarage]

"cobalt" bits is a bit of a sales pitch.

Some grades of HSS have a bit of Cobalt in them. If done right, the cobalt can add some wear resistance - so the tools should last longer - however Cobalt bits are much more brittle, so you're generally better off with good standard HSS bits around the workshop.

Typically the quality of the grinding on the drill and the quality of the heat treat is more important that which base material they use.

Same thing with "titanium" - which isn't really titanium at all, rather titanium-nitride.

Somebody figured out you can electrically deposit a coating of gold titanium nitride in a vacuum vapor deposition process. At first the TiN coating was used for corrosion resistance and esthetics, but somebody figured out the deposited stuff is really really hard.

So they tried it on a cutting edge and the cutting edge wore much more slowly, because the hardness of the TiN coating repels heat and "built up edge" at the cutting tip. However the prettiest TiN coated part on soft tool steel won't help you a bit. Get some quality dirll bits and you'll notice the differnce immediately.

.

However it's way overblown.

 

[uart]

Since cutting fluids are being mentioned here. What's the best "makeshift" cutting fluid to use for drilling steel, as in something you might just have in your workshop if you don't have the real thing. Can motor oil be used? What about gear oil.

Just wondering .... Thanks.

 

[uart]

Those titanium drills from Canadian Tire are junk

Those titanium drills from Canadian Tire are junk

I think there's an echo here.

 

[barnale]

@uart lol* true!
I also have to agree with the overall opinion of the thread- titanium is not the best material and I would definitely go for cobalt if I would have the chance to decide which one to chose! I hope this helps! titanium has too much disadvantages.. and therefore I would chose cobalt!

 

[JASTECH]

Around the house drill bit lube...hmmm, for temp it would be peanut oil, but I don't know the lubrisity of it other then dinner in stainless steel pan, lol

Look in Enco, they carry a few different ones. Budget tight? Can you afford it next month but get it this month? I have some already so I don't need to come up with it, but could use couple dollars to ship some to you if needed?

If you really need it bad and agree to the above then PM me for details.

Thanks, JASTECH

 

[jeff g]

Hi
Try Rocol Metal cutting compound, RTD Compound or RTD Liquid is one of the best

RTD® Compound
Metal cutting compound which doubles tool life

Suitable for the most severe cutting operations RTD Compound
Soft low melting-point paste
Formulated to cling to the tool providing excellent cutting performance
Application by brush - economical in use
Rolls Royce approved - Spec CSS 137
NATO stock number: 464-6766

http://www.rocol.com/corp/index.php?option=com_content&view=article&id=143&Itemid=163

& i think it is made in the USA

This is used a great deal in the UK.

Rigid is all so good i use it for cutting pipe threads.

jeff

 

[William Payne]

I work in a machine shop that specialises in tool and die work and none of the drill bits we use are titanium coated and we drill into some seriously hard stuff. In the world where I work if its to much for high speed steel then you go to carbide.

 

[Buckgnarly]

Since cutting fluids are being mentioned here. What's the best "makeshift" cutting fluid to use for drilling steel, as in something you might just have in your workshop if you don't have the real thing. Can motor oil be used? What about gear oil.

Just wondering .... Thanks.

Bacon fat and hamburger grease....seriously. I use that sometimes on the hand drill and "out of position" drilling. Sticks, works, and the bacon smells great!

I just leave an old tin can by the stove for the wife to dump all the grease into from frying pans.

 

[tkonetzke]

I have used brake clean in a pinch for cutting fluid. Its not a great lub.ricant but is an excellent coolant. I would definetly look into a real cutting fluid. I prefer hss bits, I hand sharpen them on a bench grinder.

 

[GRX]

Not a big fan of TiN coated bits myself. As mentioned above, the coating does provide some lubricity and assists in heat transfer, however, once it wears off the cutting edge it's gone. Many bit manufactures use the coating to hide inferior quality.

Typically, good Cobalt bits are made from either "T15" HSS (5% cobalt); or even better, "M42" HSS (8% cobalt). One can usually gauge the composition of their bits from a spark test on the bench grinder. M42 will have wider sparks which fork at the ends.
http://machinetoolrecyclers.com/sparktest.html

Cutting fluids: in my workshop at home I like straight 30wt for steel, kerosene for aluminum, and Cut Lube for carbide burrs when porting aluminum cylinder heads etc ...

 

[uart]

I found some info on wikipedia saying that normal motor oil is not recommended to use as a cutting fluid because of the detergency.

http://en.wikipedia.org/wiki/Cutting_fluid

Motor oils have a slightly complicated relationship to machine tools. Straight-weight non-detergent motor oils are usable, and in fact SAE 10 and 20 oils used to be the recommended spindle and way oils (respectively) on manual machine tools decades ago, although nowadays dedicated way oil formulas prevail in commercial machining. While nearly all motor oils can act as adequate cutting fluids in terms of their cutting performance alone, modern multi-weight motor oils with detergents and other additives are best avoided. These additives can present a copper-corrosion concern to brass and bronze, which machine tools often have in their bearings and leadscrew nuts (especially older or manual machine tools).

Non detergent oils like sewing machine oil or "3 in 1" type should work ok though.

 

[Schurkey]

Since cutting fluids are being mentioned here. What's the best "makeshift" cutting fluid to use for drilling steel, as in something you might just have in your workshop if you don't have the real thing. Can motor oil be used? What about gear oil.

Just wondering .... Thanks.

A cutting oil used for drilling, where it is NOT also used as a lubricant for bearings, ways, etc?

ANY lube is better than NO lube. Pretty much anything that will absorb/transfer heat will be fine. Motor oil, ATF, wax sticks (Do-All makes the stuff I'm used to) carb or brake spray, WD-40, JB-80, darn near anything will be acceptable providing that the residue doesn't interfere with subsequent processes such as painting. Company I worked for took away all our cans of silicone-based lube because the paint department couldn't clean the residue off well enough, and the paint wouldn't stick. I think there was some airborne overspray issues, too.

I have a squirt-can of Tap Free 2 cutting fluid; works great (evaporates really fast)
http://tapfree.com/productinfo.html