Rubbish centre drills

[paul]

I bought a few centre drills from Chronos a couple of weeks back as they appeared to be a bargain at about £1 a-piece. Big mistake, they struggle to make a hole of any kind and break under the slightest pressure (I broke 2 ends in half hour today). I'm going back to the £3 odd Dormer that withstood about 12 months of newbie abuse. Tut!

EDIT: the centre drills in question were 'loose' i.e. no-name unboxed.

[Tel]

Mind you, I've 'ad the same thing happen with good P&N's - in one case the point splitting in half and falling to bits.

These days I just just the el cheapos - don't hurt so much to chuck them away.

[SteveW]

Paul,

I bought some TC centre drills from (I think) JB Tooling (or similar) and have had a lot of success with them. The are very hard so won't tolerate any side loads but used correctly in the lathe they're great and weren't that expensive.

I managed to break one of mine by using it in a hand drill to drill out a bit of very hard steel I made trying to arc weld an off-centre hole. It was OK until I introduced the side load then the tit just crumbled. I'm being a bit more careful with the other end.

[waggy]

I bought some TC centre drills a couple of years ago from a stall at the Midlands exhibition, probably the same one as Steve W. They are still going strong, I suggest this is due to me lubricating them every time used.
Don't know where this came from, but I use the residue from WD40 when drilling or tapping.
Spray some fluid into a container, leave it outside for the solvents to evaporate. This leaves a waxy residue that is applied with a brush. The fumes don't smell anything like WD40 when freshly sprayed.

Waggy.

[lancelot]

Hello all,
I would suggest the reason for the points breaking off on your centre drills is that the tail stock and head stock are not perfectly in line, thus forceing the drill to try and cut an eccentric centre, not easy on a 3/32'' tipped centre drill, ;D
All the best for now,
John.

[paul]

Thanks for the tips. John I was using my drilling machine rather than the lathe and working on a regular bit of mild steel with everything set up as normal. I've got to use the other one for the next day or two so I'll see what happens but there's no doubt they don't cut anywhere near as well as the Dormer one.

[chris vine]

Hi Paul,

My only dealings with Chronos indicate that they are a helpful bunch. I would suggest you talk to them and offer to buy a better centre drill or two from them if they take back the dud ones.

If you don't ask you don't get!! They might even be pleased with the feedback.

Chris.

[ron]

Paul
I think it's the old story, you get what you pay for, I recently bought half a dozen bargain 3/16" ones and to put it politely, they're rubbish, the tip breaks easily unless you treat them like glass and one of them even started with a very small concentric cut, next time I'll buy better!
Ron

[paul]

cvine said:

Hi Paul,

My only dealings with Chronos indicate that they are a helpful bunch.

Oh yeah, I wasn't having a go at them (I've spent £hundreds with them since December) just thought it might be worth mentioning in case anyone else was thinking of buying some of their bargain jobbies.

Ron, yes I should have known better but it's always hard to resist a 'bargain' isn't it

[havoc]

Don't know. I never bought any other center drill and never broke one nor had them drill ecentric holes. But I do treat every drill like glass.

[steammadman]

Never broak a center drill, Havoc,? you can't use em much, or you've been bl---y
lucky. I've broken dozens, yes i admit it, but anyway they make damn good
small tool bits in a variety of forms, so all is not lost,.

By the way a tip i was given in my apprentice days,many many moons ago.
A BIT OF SPIT applied before you start works wonders
GO ON TRY IT IT WON'THURT YOU ,AND IT DONT COST OWT

[abby]

Its worth checking cheap drills for correct grinding , I have found many " made in China " ground back to front or with different angles on each face , they look like a bargain at the time of buying though LOL!.
Abby.

[havoc]

Never broak a center drill, Havoc,? you can't use em much, or you've been bl---y
lucky.

Not yet. But I don't spend hours in the shop like some here. One thing I learned is that when you first face a piece in the lathe and this leaves a little "pip", then you have a problem if you try to center drill that unless you use a bl***y large one.

[paul]

steammadman: I'll give anything a whirl - I'm not proud!

abby: I wouldn't know what a correctly ground one *should* look like! But I do know that I need to get most of my ordinary drills sharpened A bench grinder is a little way down my wish list just now though.

havoc: I haven't left a 'tit' in a finished piece yet but I can see that it would make starting a drill somewhat tricky!

[Deleted]

I have used some of these bargain centre drills and found that as long as you do not lean on them too heavily they will not break as often. The biggest problem I find they have is going blunt especially when used on steel.
The conundrum is do you buy a dozen cheapies or a couple of good quality ones???
As for the drill having to remove the "pip" from the job this is down to how close to centre height the lathe cutting tool is set.
I find that if you leave a pip of around 1/4" in diameter the centre drill copes quite easily

[abby]

Paul - a bench grinder should be near the top of your wish list, how do you make or sharpen your tools ?
Abby.

[paul]

abby said:

Paul - a bench grinder should be near the top of your wish list, how do you make or sharpen your tools ?
Abby.

I've only had my lathe for a couple of months and haven't given it much hard work yet so my tools are in good nick but I know I'll need to get a grinder soon. My drills are definitely getting a little blunt though.