Thread: Lubrication for & sharpening of metal drill bits

I must say Pete you seem to have an endless capacity to confound me.

On one hand you advocate the use of a drill sharpening machine, yet you admire the skills of hand sharpening and in almost the same breath you say that its too inaccurate.
You compare the results of a new drill to dull drill and a machine sharpened one, The new drill scored well with a tolerance IT9 but both your dull and sharpened one in the same class as my average freehand ground one with a tolerance of IT11.

You rubbish the use of a reamer and then say it use for more precise work. You even go on to say to use a new drill bit in place of a reamer for an intermediate between drilling and reaming but considering the cost of a reamer is about the same as it is for a quality drill, and a reamer will take to an IT7 hole why buy the new drill at all when a new reamer will give a better surface finish and less variance into the bargain? Don't answer that I already know the answer, it's what you have handy which is fine btw just hoping that you might see another way to look at it..


In the MH29 gives the practical tolerance of hole produced by correctly ground twist drills in drilling operations as IT13. Incidentally a normal tap hole only need to be IT12-13. In the small/home shop we can always push the limits of what is practical by application of skill, understanding and time or you could just spend more money. Almost all of us would already have access to a bench grinder a piece of scrap steel and some dull drills but not all of us have more money. Sharpening not necessarily the most exciting time you'll have but you are always going to learn something, hell you can even make your own drills; blacksmiths have been doing it for ages.

As a side note for those that are interested in a more acurate understanding of accuracy and precision I can sugest a very good free resource here http://www.itl.nist.gov/div898/handb...e-Handbook.pdf . It is not light reading however.

-Josh

PS Sorry Grahame and all others my last word on the thread. I Promise.

Josh I am more than happy to discuss difference of opinions with you or anyone else for that matter. Not everyone agrees with each other, it makes the world an interesting place and is a great way to learn about a topic and generally share knowledge. As you know, I can hardly be called a "yes man" and am happy to say what's on my mind, sometimes it means crossing swords, and I'm fine with that, as I'd suggest you are of a similar disposition.

As far as I was concerned the matter was closed and there was nothing more to be gained from re-hashing what I have stated many times. I do however have an exceptionally low tolerance for people who make things up, pretend people have said things, and generally create "straw man arguments" in order to further their own agenda, hence why I find myself compelled to post again.

While it seems you have an extraordinary amount of spare time, I'm afraid I don't. Furthermore, I can only speak for myself, but agree wholeheartedly with Peter, that I, and I think others, are sick and tired of reading about this topic. I have provided clear data that proves what I'd thought was common knowledge; the more accurately ground the drill bit, the more accurate the drilled hole. Hardly a revelation I'd thought. However if you wish to continue to pursue your position that an inaccurately ground bit will drill holes just as accurately as an accurately ground one may I suggest you take the discussion to PM and state your position there and see how you get on. I'd hoped that my comments about using blunt or inaccurately ground drills may help others here, but frankly I'm sick of it. You win, you've got me, you're right.

Pete

Is there a fish being caught here.

Christ bringing out a ban stick was a bit extreme...

Sure if they are abusive or post inappropriate material (maybe they did but I never saw any).... But for a slightly heated difference of opinion, we are all adults here and I am sure we could see everyone's point of view has some merit even if they put it across rather abruptly or come across as "experts".. That is all part of a normal social society as everyone is different and we need to be tolerant of even those whose opinions or posting style we may dislike.... To remove them if their only crime has been to be different or not as good at putting their thoughts into words lessens the forum IMO... it is a fantastic forum here... One of the best I have come across we way we all get along and help one another... A bit more tolerance is in order I think... Habitual trolls are easy to pick out... I would not have considered the recently departed as habitual trolls, strongly opinionated maybe, but not trolls or trouble makers.. At least not what I have seen in this particular section of the forum...

Yes yes I know you do not want to risk the forum being filtered from schools, but I highly doubt a rigorous debate like in this thread would do that... If it would then I guess they also ban what we see happen in our national parliament as well...

Originally Posted by .RC.

Christ bringing out a ban stick was a bit extreme...

The two gentlemens in question have been banned for a week, not permanently.

I would guess a lot more went down here than we can see now, as it would have been deleted. The same thing happened a few months ago between davej (now labeled a guest) and petef. I watched it all unfold, then a few hours latter it was gone.


On to the op, I mostly sharpen by hand, my old boss was one of Guido's apprentices, and we sharpened everything without jigs.
Someone commented on bits getting easier to sharpen as they get bigger. I find this true up to a point, but when you get to around 16mm I find it very hard to get equal tips.

RC, I see you have changed your 10ee from worn out to pink....does that class as an upgrade or not?

Originally Posted by DJ's Timber

The two gentlemens in question have been banned for a week, not permanently.

OK....They need a title "In the sin bin"...

RC, I see you have changed your 10ee from worn out to pink....does that class as an upgrade or not?

It is an upgrade... The bed is ground, the cross slide scraped in.. New second hand gears for the apron... Getting less worn by the week

Originally Posted by Ueee

I would guess a lot more went down here than we can see now, as it would have been deleted. The same thing happened a few months ago between davej (now labeled a guest) and petef. I watched it all unfold, then a few hours latter it was gone.

G'day Ewan, just for the record, no there was nothing else that isn't still here. Though I doubt this post will last any more than a few micro-seconds, so I hope you're a quick reader!

At the bottom of each post is a "report post" button that will report inappropriate posts to the forum's moderators. There is a post above that I considered inappropriate, no prizes for guessing which one. Rather than respond I went through the "official" channels, held my tongue, and simply reported it to the moderators to deal with. Deal with they did and advised that "I'd been warned" and both of us were therefore banned for a week for my trouble.

I have no control over what others write, but am more than capable of sticking up for myself when idiots abound. However since that's not really in the spirit of this forum I'm more than happy to fend it off to the "moderator" to deal with. However if receiving a banning is the response to somebody else's posting then I want no part of any of it. Hoo-Roo!

Pete

Originally Posted by Pete F

G'day Ewan, just for the record, no there was nothing else that isn't still here. Though I doubt this post will last any more than a few micro-seconds, so I hope you're a quick reader!

At the bottom of each post is a "report post" button that will report inappropriate posts to the forum's moderators. There is a post above that I considered inappropriate, no prizes for guessing which one. Rather than respond I went through the "official" channels, held my tongue, and simply reported it to the moderators to deal with. Deal with they did and advised that "I'd been warned" and both of us were therefore banned for a week for my trouble.

I have no control over what others write, but am more than capable of sticking up for myself when idiots abound. However since that's not really in the spirit of this forum I'm more than happy to fend it off to the "moderator" to deal with. However if receiving a banning is the response to somebody else's posting then I want no part of any of it. Hoo-Roo!

Pete

I use a product called never seize and it works brilliant when drilling holes in metal, seems to make drills run cooler and you can really see the difference when using it and when not. cheers peter

Originally Posted by Ueee

I would guess a lot more went down here than we can see now, as it would have been deleted. The same thing happened a few months ago between davej (now labeled a guest) and petef. I watched it all unfold, then a few hours latter it was gone.

Pretty sad that we lost a valuable member in DaveJ out of it. He contributed a lot! If anything I think the mods need to squash this stuff at the earliest opportunity before it gets out of hand.

Apologies for being off topic, but -

Originally Posted by variant22

If anything I think the mods need to squash this stuff at the earliest opportunity before it gets out of hand.

The mods can't be everywhere. It is more important that individual members

• behave in a respectful manner so these situations don't occur
• support and watch out for each other so that it is clear that derogatorily comments and dis-respectful behaviour have no place here
• draw things to the attention of the moderators when they start getting nasty

There are bound to be times when disagreements happen but differing points of view need to be discussed on their issues and not on the personalities involved. If there are members out there that never fail to push your buttons use the "ignore posts" setting or don't read what they say.
I've reported a few things which the mods have subsequently taken action on without any problems. I think it's like fighting at school though - once the fight starts, it doesn't matter who started it. You're both in trouble.

Michael

Originally Posted by Michael G

Apologies for being off topic, but -



The mods can't be everywhere. It is more important that individual members

• behave in a respectful manner so these situations don't occur
• support and watch out for each other so that it is clear that derogatorily comments and dis-respectful behaviour have no place here
• draw things to the attention of the moderators when they start getting nasty

There are bound to be times when disagreements happen but differing points of view need to be discussed on their issues and not on the personalities involved. If there are members out there that never fail to push your buttons use the "ignore posts" setting or don't read what they say.
I've reported a few things which the mods have subsequently taken action on without any problems. I think it's like fighting at school though - once the fight starts, it doesn't matter who started it. You're both in trouble.

Michael

The whole thing degenerated into an overblown and basically pointless argument. People over-reacted to trivia.

And I most certainly *include* the moderators for banning someone for REPORTING a post that they considered inappropriate. That is just pathetic.

Boat design dot net has a *very* effective and strict moderation policy. It uses the same software as this forum but without the sort of arbitrary knee-jerk decision making I see here. On bd.net if you manage to offend enough forum members, your reputation score sinks to the point where you can't start new threads, then eventually you can't post at all. Even if you have a huge rep score, if you break the rules, you're gone. There is ONE moderator for the whole forum because the feedback system works so well.

I'd rather be there than here frankly and if a few of the people I know in real life leave here or get the boot, I'm just staying on bd.net or PM. Having just been spending my time attending a funeral and then helping to sort out the possessions of a very good friend not much older than me, my tolerance for chicken faeces is really, really low ATM.

PDW

I hand sharpen drills up to what ever width the grinding wheel is.
Funny thing is, I can sharpen a smaller diameter drill to perform better than some new one out of a packet.
Luckily have a nice drill sharpener at work which can handle 28mm to 75mm.
Generally the holes I drill are for passing screws or bolts through, so a little bit of extra clearence won't hurt.
If you need a hole with a tight tolerance ream it, as you have to allow 0.2 for possibly drilling oversize.
Of course there are other tricks like drilling close to size, than rounding the corners with a 1mm radius on your final size drill to cut neatly to size if required.
Normally use soluble coolant or neat cutting oil for drilling to aid cooling and chip removal.
Find too high a surface speed and feed normally kills the cutting edge, and if you get it right, the drill will last for many holes without re-sharpening.

Originally Posted by Clubman7

I hand sharpen drills up to what ever width the grinding wheel is.
Funny thing is, I can sharpen a smaller diameter drill to perform better than some new one out of a packet.

That's a big claim to make Clubman, can you explain how your hand ground small drills are better than new?

Lex.