Date: Tue, 22 May 2018 14:36:01 -0700
Reply-To: Mark Belanger <mbelanger@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Mark Belanger <mbelanger@GMAIL.COM>
Subject: Re: Success - Re: Trying to drill out bolt ...
In-Reply-To: <80D76BC395C841E2BDF4FBD11CE9081D@ZoltanHP>
Content-Type: text/plain; charset="UTF-8"
Forgive me, but I was late to the party and having recently experienced
some die adventures, I'm curious which bolt this is in reference to?
Thanks much,
MB
On Tue, May 22, 2018 at 8:14 AM, thewestyman <zolo@foxinternet.net> wrote:
> Yes, finally have drilled and tapped the project.
> And it was an all day deal.
> Fortunately at Home Depot I found a set of Bosch drills 1/4 to 5/16 which
> was not for masonry but glass. It had Tungsten tips and correctly ground
> to
> sharp edge like ordinary drills.
> It did slowly cut into the broken in bolt and with a lot of patience I made
> it to the bottom end, with changing drill sizes as I progressed. Had to
> make sure, I don't slide off the center while it's progressing.
> Tapping was a little slow, but it was going all the way.
>
> Thanks to all who gave encouragement for this, especially Alistair.
>
> Forever yours, The List,
> 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
>>>
>>
>>
--
________________________________________________________________________
Mark Belanger - mbelanger@gmail.com
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