[nelsonjm]

I'm drilling a 3" 3/8" diameter hole in aluminum 6061 and broke 1" of a 1/8" hss bit in the material. How the heck do I get it out? I tried drilling down next to it and pouring an alum/water solution but after 6 hours the bit has only turned slightly darker.

pulling it out with pliers is not an option anymore, what can I do? I have a drill press and live in an apartment.. so I'm limited to what tools I have access to.

 

[97 ATX 2.0L]

If it's a through hole, drill though the back till you get to the bit then use a punch. Not a lot you can really do.

 

[nelsonjm]

Unfortunately it isn't. Dang. I was really hoping the alum would work

 

[rekoner]

Maybe you should just drill all around the broken bit and then knock it out and have a welder fill in the hole, grind it and start again. Did you use a little oil on your tap and set the speed on your drill down? Crap like this is so agrivatting isn't it!

 

[sstalder5]

could you just drill through it with a harder material bit? what exactly are you doing?

 

[nelsonjm]

I was running at 2050rpms and used 3 in 1 for lubricant.


Yes, my next attempt will be to use a standard 1/4" carbide bit. That should be able to drill through hss, right? Or is there something better?

I'm drilling this hole for a cartridge heater. It's just a block of aluminum, but I was hoping to make it look somewhat professional.having holes drill all the way through/etc would take away from that.
Oh well, it's just 20$ of metal if it doesn't work out. This is one of those things where money is more valuable than my time too.. that's why I'm trying different stuff.

 

[Icantdrive65]

Yes, my next attempt will be to use a standard 1/4" carbide bit. That should be able to drill through hss, right?

Not exactly.

Oh well, it's just 20$ of metal if it doesn't work out. This is one of those things where money is more valuable than my time too.. that's why I'm trying different stuff.

I have several hundred pounds of aluminum at my disposal, so I would just ditch the block and start anew. I under stand that it's not so easy for you to get more material, but see if you can find another piece. Maybe a local machine shop has what you need. Find a small shop and they will be more likely to help you.

 

[Sonic Reducer]

there's no silver bullet for stuff like that but try a left hand drill bit, could grab it enough to spin it back enough to loosen it. if your time is worth money sounds like another piece of aluminum would be $20 well spent and saved aggravation. maybe turn your rpm's down. i usually go around 700-800 rpm with a 3/16 pilot on my grizzly mill on aluminum and use a wax lubricant on the bit. 2050 seems very fast to me. on very deep holes like that it becomes more important to clear the chips every so often.

 

[FlyinPolack]

Is it a 3/8" hole, or a 1/8?. Well if it's a 3/8" bit heres what you do: find someone with a stick welder (or a tig, but it's harder).
Turn the welder to a low heat with a 1/8" 7018 electrode. use less than 50 amps to start, go straight down the hole & stick the rod to the drill bit. Release the rod from it's holder, put some vice grips to the electrode (that's now extending your bit) twist ccw, & you should be good.

Clamp your part better, slow down on the feed speed & use some oil next time
hope it helps.

 

[FlyinPolack]

if you have a 1/8" bit in there (for a pilot hole) this may work: drill down to it with the 3/8 bit & get a spotweld removing bit (with a removable center) you can actually core around the small bit like a mini hole saw with it. any autobody shop should have one.

 

[loco-gringo]

Where can we send the $20 for a new piece of metal???

Wumpus can tell you that I like to tackle stuff like this, but just hearing on RM doesn't really allow us to help, so I'm all for tossing it and starting over.

 

[johnbryanpeters]

There's a tool, forget what it's called, that uses an arc to burn out a drill bit or a tap. A really good machine shop might have one, but it'll be fifty bucks labor if they're kind to you. You can flat-assed forget drilling through it with a carbide bit.

 

[nelsonjm]

there's no silver bullet for stuff like that but try a left hand drill bit, could grab it enough to spin it back enough to loosen it. if your time is worth money sounds like another piece of aluminum would be $20 well spent and saved aggravation. maybe turn your rpm's down. i usually go around 700-800 rpm with a 3/16 pilot on my grizzly mill on aluminum and use a wax lubricant on the bit. 2050 seems very fast to me. on very deep holes like that it becomes more important to clear the chips every so often.

I pulled 2050 rpms from an online speed chart. That's what they recommended. I'll try going slower. Think I can use wax-based chain lube?
The entire way down I was tapping, pulling out, clearing the bit and dipping down again. These were harbor freight hss bits. The metal is being drilled in a drill press with a drill press vice.. that sucker isn't going anywhere.

if you have a 1/8" bit in there (for a pilot hole) this may work: drill down to it with the 3/8 bit & get a spotweld removing bit (with a removable center) you can actually core around the small bit like a mini hole saw with it. any autobody shop should have one.

It's a 1/8" bit that was serving as the pilot hole for the 3/8" hole. I have drilled down to it, but now it's covered in aluminum. I'm not sure how well that's going to work. I might know somebody with an arc welder however.

There's a tool, forget what it's called, that uses an arc to burn out a drill bit or a tap. A really good machine shop might have one, but it'll be fifty bucks labor if they're kind to you. You can flat-assed forget drilling through it with a carbide bit.

That might almost be worth it just to watch


Oh, I have made some progress too. I've bumped up the amount of alum in the water solution and let it sit overnight in the oven. The bit has become slightly brittle so I am able to drill down a bit more and repeat the process.. this is slowwww!

Thanks all for your thoughts.

 

[ucsbMTBmember]

Try a cobalt bit. The carbide bit will just be chipped to pieces. Or try to find an a bad end mill from any machine shop that is the same size or smaller than the bit. the end mill will chew the bit away. You need to go very slow though and use lots of cutting fluid.

 

[johnbryanpeters]

Electro Arc

 

[DirtyMike]

Your speed was fine...... Your methods were flawed.

Drilling a hole to a specified depth is pretty straight forward.

First off, a low speed drill press is best way to go. Second, stop using lubrication oil, and get some proper cutting oil. Your lubricant il most likely cause it to vibrate while drilling, and if you were using a hand held unit that means snapp. that... or you were using a handheld drill motor and got a little sideways causing the hardenned metal of the drill bit to fracture.


Now as far as geting the peice out.... if you can get the material for 20 bucks, itll be cheaper and easier to get new material. There are a couple tools. JBP listed one, there are also drill extractors as well. Work well, but they are not cheap.

 

[AngryMetalsmith]

Where can we send the $20 for a new piece of metal???

Wumpus can tell you that I like to tackle stuff like this, but just hearing on RM doesn't really allow us to help, so I'm all for tossing it and starting over.

Agreed.

Unless of course the whole point of this exercise is to satisfy obsessive compulsive tool use, then processed.

 

[TheTruth]

I'm drilling a 3" 3/8" diameter hole in aluminum 6061 and broke 1" of a 1/8" hss bit in the material.

...and today, I was riding my, 4130 chromoly hardtail frame, with the 3" 3/8" drop outs, when I decided, tooo go off a ramp. When I landed, the seat went, 1/8 of a foot, up my A$$. How, do I get this seat, out of my A$$?

William Shatner Voice

 

[nelsonjm]

Your speed was fine...... Your methods were flawed.

Drilling a hole to a specified depth is pretty straight forward.

First off, a low speed drill press is best way to go. Second, stop using lubrication oil, and get some proper cutting oil. Your lubricant il most likely cause it to vibrate while drilling, and if you were using a hand held unit that means snapp. that... or you were using a handheld drill motor and got a little sideways causing the hardenned metal of the drill bit to fracture.


Now as far as geting the peice out.... if you can get the material for 20 bucks, itll be cheaper and easier to get new material. There are a couple tools. JBP listed one, there are also drill extractors as well. Work well, but they are not cheap.

I've purchased new material.

I did use a drill press to do this. I probably just pressed down too hard and this flexed the bit/table. The lubricant probably didn't help either although to be honest, I noticed very little vibration while cutting.


The entire point to this was to see what was possible in case something happened like this again in a more expensive workpiece. You guys have offered some good suggestions.

 

[DirtyMike]

Def get some actuall cutting oil though..... Makes all the difference in how fast, smooth, and proper the cut will be

 

[AngryMetalsmith]

General rule : Never force a cutting tool, let it advance at it's own pace. If it requires force, it is too dull and should be replaced.


What are you making anyway ?

 

[MMike]

um....is no-one going to point out that his drill bit must have been completely dull? A 3/8 bit in aluminum really shouldn't require cutting fluid. Yes it doesn't hurt. But to drill 1 hole? In aluminum? a sharp bit could have made it through dry quite easily. There should have been no reason to push hard at all. Aluminum is pretty soft.

you should buy a new set of bits next time you go out.....

 

[johnbryanpeters]

um....is no-one going to point out that his drill bit must have been completely dull? A 3/8 bit in aluminum really shouldn't require cutting fluid. Yes it doesn't hurt. But to drill 1 hole? In aluminum? a sharp bit could have made it through dry quite easily. There should have been no reason to push hard at all. Aluminum is pretty soft.

you should buy a new set of bits next time you go out.....

I agree - a 1/8" bit in 6061 should not require lubricant. Another observation is that a pilot hole doesn't require to be deeper than about the diameter of the finished hole size.

 

[nelsonjm]

This was a brand new 1/8", (not 3/8" bit) bit from harbor freight. The depth of the pilot hole has been noted for next time

 

[MMike]

Ah...I caught the 3/8"

But yeah....aluminum shouldn't be that hard to drill. It's pretty soft stuff. Especially on a drill press....

 

[Icantdrive65]

This was a brand new 1/8", (not 3/8" bit) bit from harbor freight. The depth of the pilot hole has been noted for next time

There's the problem.

Sorry. Tool snob here. Really, any bit with an edge should run through regular aluminum without a fight. The problem is that the aluminum heats up and welds to the flutes of your drill bit. Clear the chips and oil the length of the bit frequently as you peck down.

 

[loco-gringo]

There's the problem.

Sorry. Tool snob here. Really, any bit with an edge should run through regular aluminum without a fight. The problem is that the aluminum heats up and welds to the flutes of your drill bit. Clear the chips and oil the length of the bit frequently as you peck down.

Yup...this is an example of a really crappy bit, or an extremely loose drill head.

 

[ridiculous]

Ive got a broken 3/8" end mill laying around if you want it.

 

[Jimmysal]

These were harbor freight hss bits.

In the future, don't skimp on tools.

For now, try welding a rod to the bit as someone mentioned above. Other solutions might be set like http://www.sears.com/shc/s/p_10153_12605_00952166000P?vName=Tools&cName=Auto&MechanicsTools&sName=Taps%20&%20Dies&sid=IDx20070921x00003a&ci_src=14110944&ci_sku=00952166000P if there's enough meat left.

I'd chuck it and buy a new block. And a better drill bit.

 

[buildyourown]

Good tools, lube, and go faster. (higher RPM)

 

[TheMontashu]

This was a brand new 1/8", (not 3/8" bit) bit from harbor freight. The depth of the pilot hole has been noted for next time

Even I know not to buy tools there.....

 

[kazlx]

There's the problem.

Sorry. Tool snob here. Really, any bit with an edge should run through regular aluminum without a fight. The problem is that the aluminum heats up and welds to the flutes of your drill bit. Clear the chips and oil the length of the bit frequently as you peck down.

That's what I was going to say. The only things I buy from HF are for non-important work like a sledge or rubber mallet. Anything you value shouldn't be worked on with HF tools....

 

[nelsonjm]

In my defense, I didn't know it was a harbor freight bit.

Also, what's should I be doing with the speed for the next drilling endeavor? I see some people telling me to run much slower, some telling me to run the same speed and now some telling me to run faster.

 

[buildyourown]

In my defense, I didn't know it was a harbor freight bit.

Also, what's should I be doing with the speed for the next drilling endeavor? I see some people telling me to run much slower, some telling me to run the same speed and now some telling me to run faster.

Most people go too slow. I would start around 1000-1200 rpm for a drill press. Let the toold do the work. A small drill should require minimal pressure. The chips should be thin.
On a good mill, you can easily double or triple that.

 

[nelsonjm]

Should I be expecting curly fry thin strips or small short chips?

 

[MMike]

small is always better


I'm lobbing a pumpkin over the plate here....any takers?

 

[buildyourown]

Should I be expecting curly fry thin strips or small short chips?

As a machinist, you want your chips to break and eject away from the work piece. This keeps them off the work. They help carry away heat and are easier to handle when cleaning up. A big birds nest of curly chips is the worst case.
The ability of the chip to break is mechanism of tool geo, alloy, speed and feeds. With a cheap drill in soft alum, you really can't help but get a stringy chip.
I know this is overly technical, but you asked. Peck the drill to break the chip(feed, retract, repeat). They will be long but they should be thin.

 

[Skookum]

So why is it that you always get a few curly fries in your regular fries when you order at Arbys? If you guys are so smart...

 

[Icantdrive65]

So why is it that you always get a few curly fries in your regular fries when you order at Arbys? If you guys are so smart...

They use the wrong oil.

 

[johnbryanpeters]

So why is it that you always get a few curly fries in your regular fries when you order at Arbys? If you guys are so smart...

They get tangled with pubic hair before cooling. Please pay at the desk on the way out.