Difference b/w drill bits

[83diesel]

I am in the market for buying a new set of drill bits. Some tool guys say titanium bits are more durable than cobalt, some say the cobalt is better. I drill a lot of stainless steel studs and bolts that are aircraft grade in hardness.

Should I just forget the Ti and Cobalt and get carbide?

Extremely tired of sharpening bits constantly when drilling stainless. Sharpen/touchup after one to two studs, and that is with oil and slower speeds.

 

[Moose-LandTran]

i've yet to buy a decent set of drill bits. but having used a friend's Bosch set (titanium coated, i believe) i can tell you that they're excellent quailty, and they really do work. used them to drill holes in the side of his Sprinter van for hih-level marker lights and they went through the sheet steel in a fraction of a second. used them on steel stock and for drilling out bolts etc. very very good. i'd definitely reccomend them.

 

[jimmycrackcorn]

Hey if you want a good set of drills, i have posted this before, norseman super premiums. Tougher than cobolt, its made out of high moly tool steel. Fastenel sells them and can be had online for under $100. They eat through everything i have put them up against, they have stayed sharper longer than any drill i owned and worth every penny....

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

 

[83diesel]

The norseman bits look okay, but it says at the bottom of the page not made for high tensile free machined ss. Says cobalt is the bit to use on free machined ss. The norsemans look like Irwin black and golds, don't get me wrong, but the studs I drill through on a weekly basis destroy good bits. Aircraft grade ss studs and bolts is the toughest material I have had to drill through.

 

[chad s]

The Norsemans ARE NOT at all like Irwin bits. I Hvae tried a lot of brands, and I LOVE my Noresman SP mechanics length bits. They drill through stainless very well, but I mostly drill mild steel.

 

[83diesel]

The Norsemans ARE NOT at all like Irwin bits. I Hvae tried a lot of brands, and I LOVE my Noresman SP mechanics length bits. They drill through stainless very well, but I mostly drill mild steel.

Most good drill bits will ocassionally drill through ss and do excellent in mild steel. My question is are the Norsemans that advertise they are not recommended for ss, are they going to last drilling ss on a daily basis.

 

[ba614]

I have alot of experience fabricating stainless steel. I think sharpening drill bits is just part of working with stainless steel.

 

[l_bilyk]

Well titanium coated bits are usually just plain old HSS bits with the coating on them... it extends the life of the bit but as soon as you sharpen them you take off the coating on the tip and all you have left is a regular HSS bit

The cobalt bits are just a HSS variant with more cobalt, resulting in a harder metal... these are usually better for stainless but there are varying qualities of these too.

carbide is better still, but they are big $$$, and if you get careless you can chip them. I had a solid carbide router bit and i nearly cried when it rolled off the bench and chipped

 

[Sticky]

Get a good set like Cleveland, Chicago Latrobe or Precision Twist. Then either learn to sharpen them or buy a drill dr and you'll be set.

 

[W-Cummins]

My question is are the Norsemans that advertise they are not recommended for ss, are they going to last drilling ss on a daily basis.

You can keep repeating that but it's not what the page says. It says that they are made for cutting work hardening stainless steel. They recommend Cobalt bits for free machining SS due to the heat produced drilling it. Now the question is are the studs your drilling free machining or work harding stainless...??

William...

 

[eschoendorff]

Hey if you want a good set of drills, i have posted this before, norseman super premiums. Tougher than cobolt, its made out of high moly tool steel. Fastenel sells them and can be had online for under $100. They eat through everything i have put them up against, they have stayed sharper longer than any drill i owned and worth every penny....

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

I have been wanting a set of those... might just have to break down and get a set after my tax return comes....

 

[83diesel]

I have alot of experience fabricating stainless steel. I think sharpening drill bits is just part of working with stainless steel.

That's what I was wandering if it was just part of working with ss. Thanks for the input.

Well titanium coated bits are usually just plain old HSS bits with the coating on them... it extends the life of the bit but as soon as you sharpen them you take off the coating on the tip and all you have left is a regular HSS bit

The cobalt bits are just a HSS variant with more cobalt, resulting in a harder metal... these are usually better for stainless but there are varying qualities of these too.

carbide is better still, but they are big $$$, and if you get careless you can chip them. I had a solid carbide router bit and i nearly cried when it rolled off the bench and chipped

I have been told that by numerous people, thanks for helping me remember. Many sales people try to pawn the ti coated drill bits as being better, but I am with you, once you sharpen or wear through the coating it is not any better than a HSS.

You can keep repeating that but it's not what the page says. It says that they are made for cutting work hardening stainless steel. They recommend Cobalt bits for free machining SS due to the heat produced drilling it. Now the question is are the studs your drilling free machining or work harding stainless...?? William...

I am drilling a harder grade than grade 8 or equivelant of metric grade bolts and studs. If the mfg does not recommend them for heated work and ss than they are not for my type of work. The drill bits get hot quickly and again I am working with a lot of SS fasteners. Like I said before they are probably really good drill bits, but if the tool is not made for the application why not buy the tool that is.

 

[seattlemart]

I am going to be an Auto Tech. I am going to start school at the end of this month. I was thinking about getting a drill bit set also. I can get this 29 peice set http://www.matcotools.com/Catalog/toolcatalog.jsp?cattype=T&cat=2212&page=1&#32858 for $79.82 or this 29 piece set http://www.matcotools.com/Catalog/toolcatalog.jsp?cattype=T&cat=2212&page=2&#54413 for $82.03. Anybody have any experience with either of these or should I shop else where? Thanks for your input!!

 

[chad s]

I have been wanting a set of those... might just have to break down and get a set after my tax return comes....

You will not be dissapointed! I have had my set for almost a year, and they have been one of the best tool purchases I have made in the last year!

 

[krusty the clown]

I am going to be an Auto Tech. I am going to start school at the end of this month. I was thinking about getting a drill bit set also. I can get this 29 peice set http://www.matcotools.com/Catalog/toolcatalog.jsp?cattype=T&cat=2212&page=1聚 for $79.82 or this 29 piece set http://www.matcotools.com/Catalog/toolcatalog.jsp?cattype=T&cat=2212&page=2풍 for $82.03. Anybody have any experience with either of these or should I shop else where? Thanks for your input!!

the prices you posted are about $100 less than listed on the website. are those prices through the votech program?

 

[seattlemart]

the prices you posted are about $100 less than listed on the website. are those prices through the votech program?

Yes it is with the student discount taken off the retail. Should I get one of these or a set of norseman?

 

[krusty the clown]

i'd go with the norseman's over hss bits.

 

[Kevin54]

I am drilling a harder grade than grade 8 or equivelant of metric grade bolts and studs. If the mfg does not recommend them for heated work and ss than they are not for my type of work. The drill bits get hot quickly and again I am working with a lot of SS fasteners. Like I said before they are probably really good drill bits, but if the tool is not made for the application why not buy the tool that is.

Carbide would be the one to last the longest, but they are the most brittle. And if they start breaking the cost can beat you down. At an average price of $10-30 a bit, you would want to be real careful. Then you would need a diamond wheel to resharpen them, so that is a little chunk of change in itself. You may have to change the type of lubricant that you are using to prolong the life of your bits and change your feeds and speeds. I would do a search for stainless steel lubricants for drilling and try that first. One thing that may be happening, without the proper lubricant to keep the bit and metal cool, you could actually be work hardening the stainless as it heats up. The faster it work hardens, the quicker the bit deteriorates. On some things at work, we just use oil for a lubricant, but when we get into more exotic metals, we change to either a chlorinated wax, Tap Ease, or one of a couple of others that escapes the mind at the moment. Take a look at this and see if this may help you out http://www.manufacturingtalk.com/guides/cutting-fluids.html