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!!!! SO wrong !!!!

Paraffin is good for Aluminium but not Steel - WD-40 is not a lubricator!

Cutting Fluid is probably the best but any 'oil' would do - or possibly nothing depending upon the grade of steel.
WD40 has for decades, been considered to be a 'toolkit in a can' to do lots of things, not of them particularly well, (notably as a penetrant and lubricant), but WD40 (The company) does have a 'specialist' range, which includes cutting oil:

https://wd40.co.uk/product/multi-purpose-cutting-oil/
Likewise, a penetrant:

https://wd40.co.uk/product/fast-release-penetrant-spray/
The full range is here:

https://wd40.co.uk/products/wd-40-specialist/
David.
 
Here's just some tips from my recent work on the drill
Poor mans clock, much better than a square.
Tramming table.png

Height gauge
Tramming vise.png

Making sure I've sharpened them correctly
Drill sharpening gauge.png


The proper way, or should that be the only way to use a chuck key, in the left hand, that is.
I see a lot of folks haven't experienced a chuck what's seemingly been used without a key before,
but regardless, good practice.

Also featured, a long bit for noting runout, should the MT need a bit of trial and error re-fitting.
Chuck in left hand.png


The scissor jack isn't for rigidity nor for use raising the table, note the gap between it.
It's for a lateral stop, which is the solution, regardless of how it's done.

Perhaps easy to imagine a big heavy dense timber square there instead, or even something bolted to the green TS to register/index/contact with.
Can be as simple or as complicated as you like.

SAM_5730.JPG


Tom
 
I usually find the right speed gives good size swirling swarf. Too slow and the drill hardly cuts, too fast - worse and the chips become very small and steel work hardens.
 
WD40 has for decades, been considered to be a 'toolkit in a can' to do lots of things, not of them particularly well, (notably as a penetrant and lubricant), but WD40 (The company) does have a 'specialist' range, which includes cutting oil:

https://wd40.co.uk/product/multi-purpose-cutting-oil/
Likewise, a penetrant:

https://wd40.co.uk/product/fast-release-penetrant-spray/
The full range is here:

https://wd40.co.uk/products/wd-40-specialist/
David.
I'm well aware that there is now a 'range' of products but there is a tendency for too many people quoting 'WD-40' as a panacea without referencing the specific product which usually means that they are talking about the original.
 
Thanks to all who have contributed to this thread and to the OP for raising the issue.. In my ignorance I always imagined it was sensible to drill big holes in small stages, but never could do it very well. I understand why now. Live and learn, eh? I'm 76.
 
I understand why now. Live and learn, eh? I'm 76.
Yes we really never do stop learning and it is for me very enjoyable. Only last year on a speed awareness course I learnt what a dual carriageway is after forty plus years of driving, amazing. I had always thought of them as anywhere you have two or more lanes in the same direction, not the case and for those not in the know there needs to be some form of central barrier between the two directions of traffic to keep them apart. The tutors way of remembering this was just to think if you could roll a ball from one side to the other without obstruction, yes some smart rear ends will just say what if it passes under the armco but the tutor pointed out it was a large ball !
 
I had always been told to start small and move up in stages, incorrectly it seems. I'll adjust my technique in future. One question though, the general advice on this thread seems to be centre punch, pilot drill, then full size, I'm wondering why you need the pilot bit though, the centre punch gives a guiding divot to start the cut, so why can't you just go straight onto that divot with your full size bit? Or is it to give somewhere for the swarf to go?
 
Yes we really never do stop learning and it is for me very enjoyable. Only last year on a speed awareness course I learnt what a dual carriageway is after forty plus years of driving, amazing. I had always thought of them as anywhere you have two or more lanes in the same direction, not the case and for those not in the know there needs to be some form of central barrier between the two directions of traffic to keep them apart. The tutors way of remembering this was just to think if you could roll a ball from one side to the other without obstruction, yes some smart rear ends will just say what if it passes under the armco but the tutor pointed out it was a large ball !
odd that he felt to patronise with the example of a ball, how about 'is there a barrier and more than one lane'?
 
Think of the pilot hole as a continous centre dot that helps guide the drill on it's passage through the material.
so if you were to remove the need for accuracy (for a rough project say), you'd just go straight in with a big bit, no pilot, no punch?
 
odd that he felt to patronise with the example of a ball,
I think he was amazed when he realised how few of us could define a dual carriageway, few got the speed limit right and some even stated it was where you can go fast and overtake the slow coaches. The idea of rolling a ball did hammer home the true definition and another one is NSL, no street lights or national speed limit and it must have worked as I now remember them. Perhaps it was much easier forty plus years ago to pass the test !
 
I'm wondering why you need the pilot bit though, the centre punch gives a guiding divot to start the cut, so why can't you just go straight onto that divot with your full size bit? Or is it to give somewhere for the swarf to go?
The reason for pilot drilling is to be large enough to cover the web of a large drill bit making it easier to drill through/into material. The web is the part between the two cutting edges, and is right in the centre of the drill bit and does not cut the same as the two cutting edges meaning more force is needed to push the bit through
 
so if you were to remove the need for accuracy (for a rough project say), you'd just go straight in with a big bit, no pilot, no punch
I would always use a centre punch or something to make an indent. The rest depends what you are drilling and the size. For thin sheet metal then a hole saw or flycutter and you could just drill a hole without a pilot if you are not looking for accuracy, as I said for precise location use an optical punch.
 
If you have a 4 facet point there's no central web it's now a point! But a small pilot hole still helps. As often used, the pilot drill should be large enough in diameter to be easily sharpened.
 
Regardless of the bits used, the fundamental issue is with the changing of the size drills.

Most of the ubiquitous machines made for the last donkeys years, don't have enough travel of the quill to peck a hole and swap out to a large bit without moving the table.

They also don't have a table with a raising knee like on a mill, and that looks a bit involved and possibly troublesome if using linear bearings and a bottle jack or motor.
That would do the same job, as in keeping the work centered.

Easiest bodge is something rigid and parallel with the column, so you can swing the table over until contact, then tighten the lock.
(whilst letting it do it's thing, no lateral pressure required against the stop)

Tom
Easy way is to use a rod with an angled tip on it the same size as your pilot drill, transfer punches are good. Drill pilot hole, lower table, insert rod of a similar length to your next drill in chuck then lower into your hole and position the table so the rod enters the hole cleanly without deflection, then tighten the table. By moving the quill up and down you can easily see if the rod is going straight in or slightly off. With a bit of practice you can do the same using the tip of the larger drill. This of course assumes that the work is secured to the table in a vice, so it is only the side to side positioning you have to worry about. I generally use a 6mm pilot drill and have a 6mm rod about twice it's length. Not of course super accurate, but good enough for most purposes. If you want super accurate then you need a mill.
 
I'll give the techniques mentioned a go, cheers.

My thinking for drilling in stages was to reduce the stress on the drill. Less stress, less wander, straighter hole?

Assuming your machine has the power, I would have thought using a spotting drill, and then straight to the desired size (using a stubby bit) would be the most accurate? as wouldn't a 5mm drill for the pilot have more chance of deflection?

I find it odd that you can get full size cobolt bits for a reasonable price (e.g £50 a set), but not short stubby cobolt bits.

These are reasonable price if you want 10x, but still not in a full range of sizes
https://www.ukdrills.com/hss-drills/cobalt-stub/cobalt-stub-drill-bit
https://www.ukdrills.com/hss-drills/hss-stub/hss-stub-imperial-double-ended
 
I'll give the techniques mentioned a go, cheers.

My thinking for drilling in stages was to reduce the stress on the drill. Less stress, less wander, straighter hole?

Assuming your machine has the power, I would have thought using a spotting drill, and then straight to the desired size (using a stubby bit) would be the most accurate? as wouldn't a 5mm drill for the pilot have more chance of deflection?

I find it odd that you can get full size cobolt bits for a reasonable price (e.g £50 a set), but not short stubby cobolt bits.

These are reasonable price if you want 10x, but still not in a full range of sizes
https://www.ukdrills.com/hss-drills/cobalt-stub/cobalt-stub-drill-bit
https://www.ukdrills.com/hss-drills/hss-stub/hss-stub-imperial-double-ended
What's the benefits of stubby drills?

If the drill is bending then theres too much pressure?
 
You really want to start with a centre punch mark to start it off, then you shouldn't get any wander. Pilot drills, the type with a very short tip, are really intended for use in something like a lathe where you are drilling straight into the work without any sort of mark to begin with. In those circumstances a normal drill will wander. Stubbys are generally for where access is an issue, making it difficult to use a normal.length one. I regularly use bits down to fractions of a mm, and you won't get any wander if they are started in a punch mark, and they are sharp. I also have a set of extra long ones, so for example 5mm but 120mm long. They don't wander either. If you are getting wander then the most likely cause, assuming the bit isn't actually bent, is that it's not sharp or the tip isn't correctly formed. This can be a problem sometimes with cheap ones, the tip is sometimes not evenly ground so its not actually in the middle, the smaller the bit the more important this is. Any of these problems and you end up having to apply too much pressure, which can then make it wander more, or even break. Not having the piece held securely can also cause problems. You will also find it difficult if the quill on your press is worn and allows the chuck to wander about. As a rule of thumb regarding pilot hole versus final size, you really want at least 2/3 of the width of the cutting faces on the bit to actually be cutting. This minimises heat build up and wear, so you get a more accurate hole, and your bits last longer.
 
You will also find it difficult if the quill on your press is worn and allows the chuck to wander about.
That's a very important consideration for @bertterbo
I've got quite a bit of slop on my machine, as do plenty others, so the first peck
can still be hit and miss for me, but if I've got that right, then the method will take care of the rest.

Worth mentioning it's a good idea to keep the original for a nice wee while, after getting another,
until you've experienced what the quill and MT is like on the new one, it could be much worse on any new machine what's in that category.
You could swap those bits and compare them using a long bit..

Many who seek better results again, will have to get a dial indicator,
to check both MT's, and possibly a new chuck too.
Once you got there, the price has gone up, possibly into good running used machinists pillar drills.

Not sure what pulley system is on the Warco, is it a Reeves drive, or done electronically?
Maybe one other option might be to seek whether a VFD/inverter and three phase motor
(dual voltage with 220v on the plate, with same shaft size, and ideally motor mounting type the same) might be worth seeking instead,

Knowing it's not great practice to try and get everything from the one pulley,
motor will heat up if not running at 50hz,
but I suspect it might be a suitable for non industrial purposes,
provided you get a good brand VFD with overload motor protection and possibly Vector
spec aswell, @Myfordman or 9fingers at the other place 2 (TWH2) would advise on that,
as the cheapies don't respond well, nor the motor either, if it gets bogged down.

Tom
 


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