Alistair,

Thanks  for the info.  Yes, you are kind of preaching to the quire, and let
me know all the things I already knew.
The tungsten ended drill is the one I was about to try, only I don't have
the right grinder stone here for that, but even the one I have can do it
only takes longer to make a sharp edge on it, because the blunt one it has
is made for masonry.
I can see, you have gone through yourself all the tests with these kind of
things.
No, you did not offend me a bit, and I very much appreciated your energy put
into the helping.
We often have to repeat things when we teach while we tell new things also.
That is why I asked if there was something better system than what I already
know.
This bolt end must have been hardened while heated up.
I'll go to the shop and get a small masonry drill for this and will come
back with the result, Sir.

Zoltan

-----Original Message-----
From: Alistair Bell
Sent: Sunday, May 20, 2018 10:35 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Trying to drill out bolt ...

Zoltan,

Forgive me if I come across the wrong way here. You might already know this
but I’ll say it anyway.

If the drill bit does not cut into hardened material ( in your case it’s
probably work hardened), ie no shavings right from the get go, then it will
not cut. Stop, don’t just try pushing harder, you’ll just burn up the bit.

Same thing if you are drilling successfully and then it seems not to drill ,
or requires more down force, stop.

If the bit is at all dull, I mean not fresh out of the package or freshly
sharpened, then it’s going to heat up and dull very quickly on hard
material. It’s a progressive thing, slightly dull cutting edge makes
friction and heat which makes the edge duller which makes more heat , etc
etc.
If good and sharp then this progression is less likely to occur. And of
course cutting fluid really really helps.

Cutting oil/fluid both cools and lubricates

I’m going to assume you don’t sharpen your own bits , so if the bit don’t
bite, try another fresh one.
If indeed this bolt has been work hardened, once you penetrate that hard
layer it should drill  out fine.

Use cutting oil. Almost any oil will do in a pinch. Even bacon fat is good
with steel. WD-40 or kerosene with aluminum.

And here’s a bit of a last resort. To get thru any hard layer. Use a small
carbide tipped masonry bit. You know they type, they are everywhere. Couple
of brazed on carbide cutters on the end of a twist drill. Get a small one
and have at the bolt. It won’t be pretty but if might get you going into the
softer metal.

Good luck

Alistair

> On May 20, 2018, at 8:36 AM, thewestyman <zolo@foxinternet.net> wrote:
>
> Alistair,
>
> Yes, I could make a nice center punch hole, yet I can't even start a
> miniscule of shaving.  And I have tried several small drills, 1/8 sizes.
> Tried slow, fast.  Did not use any cutting oil though.  That might help to
> start it.
> I even heated it up, hoping that would make it softer.  Probably made it
> harder.
> Last week I drilled one out without any trouble.
> This cobalt drill does not have a grade written on it.
> I think, there are 35 and 42 grades.
> These are new drills, well ground, not pushing.
>
> Zoltan
>
>
> -----Original Message----- From: Alistair Bell
> Sent: Saturday, May 19, 2018 9:18 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Trying to drill out bolt ...
>
> What bolt is this?
>
> There are drill bits and there are drill bits.
>
> Cobalt by itself means little unless backed up by some numbers and a good
> brand.
>
> If you can make a punch mark with a centre punch on the bolt, then you can
> drill it.
>
> Start with small drill bit, use cutting oil, plenty. Does it bite?
>
> Sometimes you can work harden what you are trying to drill. Usually that’s
> because of dull bit, too fast, no cutting fluid.
>
> It happens in stainless sometimes. Swap out bit, try again slower.
>
> Alistair
>
>
>> On May 19, 2018, at 9:10 PM, thewestyman <zolo@FOXINTERNET.NET> wrote:
>>
>> Yup, trying but I can’t even start it, so hard.
>> I have no idea what makes it hard like glass, but the cobalt drill won’t
>> even start any shaving.
>> This cobalt drill is from Home Depot.  Maybe there is one harder than
>> this.
>> Anyone has an idea what to do?
>> I have already installed the head, would not like to take it off.
>>
>> Best regards to the Great List,
>> Zoltan
>