Drill bits

[mojo]

I have a set of these drill bits and really like them (and I see they raised the price since I bought my set)http://buy1.snapon.com/catalog/item.asp?P65=&tool=all&item_ID=7742&group_ID=931&store=snapon-store&dir=catalog
Those bits will cut just about anything if you use a good cutting oil, except boron, but that's a whole different animal.
Also, when using a tap for cutting new threads, it's VERY important to use cutting oil.  If you don't, the tap can get plugged up with metal shavings and break the tap when you back it out of the hole.  Ask me how I know.

[teddy037.2]

If you don't, the tap can get plugged up with metal shavings and break the tap when you back it out of the hole.  Ask me how I know.

everyone does it once 

[Monsterlover]

It all comes down to the right tool for the job. . .

If you're trying to remove a headless bolt and you can get to the back side of said bolt. . .

use a drill press with a RH twist bit, push hard and it should "unscrew" the broken bolt.  If you have a 1/8 drill in there, push hard enough to start bending it, but not so hard it snaps.  You need it to really "dig" into the bolt material to provide leverage to unscrew it.

If you can't get to the backside and haven't already messed up the exposed bolt surface. . .

take it to a weld shop and have them tack weld a smaller bolt to what's left.

Remove as normal.

Precision Twist Drill makes just about everyone's private label drills.  I don't specifically know they make SnapOn's drills, but it wouldn't surprise me.

Coatings on drills DO make a difference.

But not in a home shop or with a hand drill so don't spend the extra money on them.  Just get a decent set of Jobber Length HSS with black oxide coating.  My favorite all around drill for metal.

For tougher jobs go with split point cobalt drills.  They can spin a little faster than a HSS JL drill and stand up to heat and abrasion better (cause of the higher cobalt content)

Carbide drills are really only useful if you have a CNC machine to put it in.  Sometimes a bridgeport will work, but the setup needs to be rigid or the drill will chip.

Carbide is like 90Rc and doesn't tolerate movement/vibration too well.

Carbide tipped drills are, for the most part, junk.  They're ancient technology.  Well, unless you're needing to drill concrete, but that's an entirely different drill design.

[Popeye the Sailor]

It all comes down to the right tool for the job. . .

If you're trying to remove a headless bolt and you can get to the back side of said bolt. . .

use a drill press with a RH twist bit, push hard and it should "unscrew" the broken bolt.  If you have a 1/8 drill in there, push hard enough to start bending it, but not so hard it snaps.  You need it to really "dig" into the bolt material to provide leverage to unscrew it.

If you can't get to the backside and haven't already messed up the exposed bolt surface. . .

take it to a weld shop and have them tack weld a smaller bolt to what's left.

Remove as normal.

Precision Twist Drill makes just about everyone's private label drills.  I don't specifically know they make SnapOn's drills, but it wouldn't surprise me.

Coatings on drills DO make a difference.

But not in a home shop or with a hand drill so don't spend the extra money on them.  Just get a decent set of Jobber Length HSS with black oxide coating.  My favorite all around drill for metal.

For tougher jobs go with split point cobalt drills.  They can spin a little faster than a HSS JL drill and stand up to heat and abrasion better (cause of the higher cobalt content)

Carbide drills are really only useful if you have a CNC machine to put it in.  Sometimes a bridgeport will work, but the setup needs to be rigid or the drill will chip.

Carbide is like 90Rc and doesn't tolerate movement/vibration too well.

Carbide tipped drills are, for the most part, junk.  They're ancient technology.  Well, unless you're needing to drill concrete, but that's an entirely different drill design.

Your post is utterly boring.

[teddy037.2]

Your post is utterly boring.

I disagree 

[ducpainter]

Your post is utterly boring.

Friggen engineers...

push away from the desk and...

pick up a drill bit for cryin' out loud.

[teddy037.2]

Friggen engineers...

push away from the desk and...

pick up a drill bit for cryin' out loud.

but without that shameless disconnect, what are we to gripe about over beers after work? the engineers can't know what we do; it would make things too easy!

[ducpainter]

but without that shameless disconnect, what are we to gripe about over beers after work? the engineers can't know what we do; it would make things too easy!

They're too busy reading about how dood...

not to worry.

Everything is everything.

[Popeye the Sailor]

but without that shameless disconnect, what are we to gripe about over beers after work? the engineers can't know what we do; it would make things too easy!

Hey hey hey!

Just go make it how I wanted it made. Ignore the print.

[ducpainter]

Hey hey hey!

Just go make it how I wanted it made. Ignore the print.

They all know how to draw....

[sno_duc]

Monsterlover's post was spot on.
If you can find them I really like either stub drills or 6" aircraft drills, both have reduced (about and inch) length flutes. I you think about it how often in metal do you drill thru more than an inch of material. With less flutes they are a lot less prone to becoming two piece drill bits.

Taps... my favorites are two flute spiral point (gun taps), they also make a version for blind holes (looks like a corncob).

Monsterlover do you remember 'Tap Free' in the red and white tin cans, smelled like cinnamon. Has since be outlawed because it had trichloroethane in it, great stuff especially in SS.

[teddy037.2]

Hey hey hey!

Just go make it how I wanted it made. Ignore the print.

haven't heard that one before

[Popeye the Sailor]

haven't heard that one before

Yeah but you know it's true.

[teddy037.2]

Yeah but you know it's true.

yeah...








sad...


our engineers are a bit more passive aggressive   

[ducpainter]

Yeah but you know it's true.

Tolerances...

are just guidelines...

if you're the one drawing the print....