Drill sharpener

[Steve HuckinsParticipant @stevehuckins53362]

I have purchased a drill grinding attachment, the generic type that swings at a bench grinder.  I have looked at various videos showing how to set it up and use, but wondered what your views are regarding whether it should be mounted in front of the grinding wheel or to the side.  If used on the front, there is obviously a small hollow grind to the drill bit  but the advantage would be that the wheel can be dressed when it is no longer flat. However, using the side of the wheel would give a flatter edge to the drill but how then could it be dressed once the wheels side flatness is lost ?

The other piece of advice please is what would you all recommend is the best way to buy BA taps ?  In a set or individually.  Would it be better to get all three taps in each size or just two ? I guess it will be down to quality as well. So where to buy from your experiences ?

Thanks all.

Steve

[peak4Participant @peak4]

Depending upon your grinder, you could use a wheel like this.
I have one, but fit it to a Clarkson tool & cutter grinder.
Obviously it’s designed for a bench grinder

Obviously there will be other sources and sizes available

Also, Harold Hall’s site is worth a read about drill sharpening

Bill

[Ady1Participant @ady1]

I found this video useful for showing me what tool and cutter grinders do

[bernard towersParticipant @bernardtowers37738]

Use the front of the wheel , the slight concave face to the cutting edge will not make any difference. Even with the cheap and cheerful attachment that you have will make a much better job than off hand grinding and if used carefully you will end up with a drill that has even sized lips which is the holy grail for getting right sized holes. Practice,Practice, Practice!

[noel shelleyParticipant @noelshelley55608]

Vastly better than nothing, but they take some getting used to. If like some bench grinders it vibrates due to the wheel being out of balance then it will give poor results. Bills reference to Harold halls article is worth reading it will give you the basics of what has to be done . Good luck Noel.

[duncan webster 1Participant @duncanwebster1]

I think Graham Meek did an article in ME or MEW on how to modify those die cast things so they work better. No idea of issue, but if my memory of GM is correct he might chip in

[Thor 🇳🇴Participant @thor]

Gray’s excellent posts on the MEM site is still there.

Thor

[Chris CrewParticipant @chriscrew66644]

If you mean by the ‘swing type’ drill grinding jig it is of the die-cast ‘Picador’ type you will find it almost useless, insofar as it will not generate any backing-off of the cutting edge if just swung against the side or face of the grinding wheel and the drill will not cut. The rear knurled thumb-wheel screw and cup-washer, which form part of the back-rest, are not there just for initial setting up. When you have set up a drill bit for grinding put a mark on the thumb-wheel and a fixed point on the back-rest. As you stroke the drill across the side of the wheel advance the thumb-wheel about a quarter turn and then re-align the marks again for the second stroke. This will back-off the cutting edge and the re-sharpened drill will now cut.

If you can get hold of one, the ‘Reliance’ drill grinding jig, as once made by H.D. Murray & Co. of Ponders End is by far a better design, although they were quite crudely manufactured. This is because the drill bit is caused to ‘roll’ across the side of the grinding wheel and the cradle it lies in is off-set to the axis of the jig. This automatically generates the required backing-off of the cutting edge. I don’t know the availability of these jigs on the second-hand market, I don’t think that they have been made for many years now, but they came in three sizes. No.1 for 1/8″-1/2″, No.2 for 1/2″-1″, No.3 for 1″-2″ drill bits. Provided your grinder spindle has little of no end-float, and you exercise care and common sense, there should be no problem in grinding on the side of the wheel in fact most jigs are designed to be used this way.

The jig, as supplied, has a cast slotted bracket for mounting against the side of a wheel with No.1 jig shown in the first photograph. The 2nd & 3rd photographs show the No.2 size jig mounted on home-made bracket and holding a 15/16″ drill. In the second photograph you can detect the off-set of the cradle to the axis of swing.

 

 

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[Les RileyParticipant @lesriley75593]

I would second Chris’ post above. I have all three sizes of Reliance and have happily been producing perfect drill tips with them for many years. The Picador et al type really is rubbish!

Watch eBay and bide your time and you can get a smallest Reliance for around £30. The smallest is the most useful one for most folks work size.

[Steve Huckins]

On 10 January 2024 at 17:42 Steve Huckins Said:

…

The other piece of advice please is what would you all recommend is the best way to buy BA taps ?  In a set or individually.  Would it be better to get all three taps in each size or just two ? I guess it will be down to quality as well. So where to buy from your experiences ?

Thanks all.

Steve

The answer depends enormously on what the workshop does.   Buying a complete set of all BA, Metric, BSW, BSF, Unified and other taps is hugely expensive, especially if only the best will do.   Tens of thousands.

I started by having a think about what my workshop was for:  it’s mainly experimental work, mixed with electronics and radio.  As I rarely repair old machines or build models from old plans, I don’t have much call for BS or UN threads:  when one of them is needed I buy or make the tap &/or die.

Metric threads are ideal for experimental work and repairing modern equipment.  Unlike legacy threads they are readily available and mostly a shade cheaper.   It made sense for me to buy a basic metric set covering the most common coarse and fine threads up to M12.  The set only has taper taps, and if I need a second or plug variant, I buy one.   In practice, I limit the number of threads I use, notably M2.5, M4, and M10, and for these only I have all three tap types.  Metric also fits experimental work, where the maths and CAD are both easier than thinking in Imperial, unless of course you’ve spent a lifetime thinking in Imperial, and metric requires an old dog to learn new tricks!

BA is common in old British instruments, and for these I’m still using a basic Carbon-Steel set bought over 50 years ago.  It’s lasted because it’s only used to tidy up existing threads, corroded or mangled, and to cut new threads in Aluminium.  The nature of BA is that most threads are put into through holes, so bottom taps are rarely required.  Apart from radio repair work I avoid BA – it’s a little hard to source BA and metric fasteners are just as effective.

As a rule of thumb, if you don’t know yet what threads will be needed in your workshop, buy a basic set to get started.  After a while, it will probably become apparent that some sizes are never used, whilst others have a hard life.   Replace only the sizes that get used, perhaps buying in bulk.  These are also likely to be the sizes where it’s worth buying taper, second and bottom taps.  Again, what you do matters – tapping into blind holes means bottom taps are essential, otherwise not.

Same rule of thumb applies to drills.  Worth starting by buying a set, but thereafter only replacing the sizes that are used a lot.  Experience identifies what’s needed, and restoration is different from loco building, which is different from what I do.  Like as not, it will be realised that although inexpensive tools are good enough for most work, there are jobs were better is needed.  I hate the word ‘quality’ because it’s meaningless without a specification.  However, many like to use the best possible tools.  Trouble is, these are shockingly expensive, and only make financial sense in a professional setting. Second-hand is a possibility, but there’s no guarantee the tool will be in good condition.   I’ve pretty much settled on mid-range tooling, mostly avoiding very cheap internet ‘bargains’ and high-end industrial because both waste my money.  I say mostly avoid because a cheap tap that only has to be used once is worth the risk, whilst sometimes it’s worth going up-market, as when I had to drill a lot of holes in work-hardening stainless.

The exception is a professional or busy general purpose workshop.  When time is money, it might pay to keep a full range of well-specified tools on hand. Having an expensive skilled man down tools because there isn’t a tap on the shelf is painful.  And although hobbyists are famous for not wanting to spend money, having to stop whilst a tool is bought is frustrating!   If money is no object, and there’s plenty of space, why not enjoy the hobby by starting with a fully equipped workshop?

One thing – do you really need BA?  There are good reasons, but…

Dave

 

[peak4Participant @peak4]

The whole topic of drill sharpening has been covered many times on here; if only the forum’s search engine worked better.

1. Drill Sharpening using the Quorn
2. Drill sharpening?
3. The Correct Way To Sharpen Drill Bits Using A Picador Drill Sharpening Jig With Custom Base
4. Chosing a drill grinding attachment or machine
5. Drill Sharpeners Compared.

The  above are topics where I have made a post, linked not because I claim to be an expert, but because it’s easiest to search my own posts, in this case for “Picador”
Some of the above contain links to other articles.

The genuine Picador one does seem to work quite well straight out of the box, unlike many of the similar ones, which rely on a subtly different geometry.
At least one of those topics shows a box with Picador instructions for the genuine article (only).

Bill

[Dave HalfordParticipant @davehalford22513]

This is a version of as ‘all Chinese lathes are the same’.

Like the Picador they are not, the cheap ones are just look alikes, the angles are wrong.

 

I have bought several tap sets of three from Proops – all have been good.

[Bill PhinnParticipant @billphinn90025]

I own a Picador, a Spiralux and the small version of the Reliance. All work well in the right hands. I use and prefer the Picador most.

[Chris CrewParticipant @chriscrew66644]

 “If money is no object, and there’s plenty of space, why not enjoy the hobby by starting with a fully equipped workshop?”

What is a fully equipped workshop? I have been collecting machines and tools for nearly 50years and have amassed a collection some people would almost kill for. I have lathes, grinders (both cylindrical and surface), milling machines (horizontal and vertical), shapers, pillar drills (bench and pedestal) and every machine is tooled from ‘backside to breakfast time’ with both OEM and shop-made accessories. And what have I produced over the years with all this wonderful kit? I have to say not a lot, notwithstanding the fact that I was an itinerant contractor during my working life and spent the majority of my time away from home. So some people, who seem to be able to produce wonderful work in industrial quantities in workshops that, by comparison, are very sparsely equipped might say I have all the gear, but no idea I wouldn’t argue with them.

Like some people collect stamps, simply for the pleasure of just owning them, so I collected machines and tools. But I was lucky: before auctions went online and at the time Mrs. Thatcher was busy closing British manufacturing industry, working mostly nights, I had the opportunity to visit many factory liquidation sales. This, coupled with a changing technical education curriculum that closed school workshops, meant that the market was flooded with kit the auctioneers could hardly give away. It’s never going to happen again and some items I have must have appreciated in value and some depreciated but all of it has given me pleasure over the years and still does.

[Steve HuckinsParticipant @stevehuckins53362]

Thanks everyone for a good variety of advice.  I have binned one of my Picador copy types having seen the angles are all wrong.  I also ground a 10mm drill on it and it looked more like a javelin than a drill !  However, an old Draper one I found second hand which was manufactured in Japan appears to be miles better.  But I think I will try to find the smaller Reliance and be patient.

The BA drills I have purchased as a set of 0 to 10 and then I will buy better replacements for the most used, as advised.

Hoping to start my journey soon by making the Stuart S50 received for Xmas.

Happy New year to all.

Steve

 

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