# Imperial drill bits



## NickDReed (8 Jun 2022)

Hi all, 

Anyone know a good place to purchase imperial drill bits? 

Specifically 1/2 inch? 

Regards 

Nick


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## Inspector (8 Jun 2022)

HSS DRILL BIT 1/2 - Chronos Engineering Supplies


HSS DRILL BIT 1/2 from Chronos Engineering Supplies. Free UK delivery and great worldwide rates.




www.chronos.ltd.uk





Pete


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## PDW125 (8 Jun 2022)

Tend to use drillfix for all the non standard sized stuff









HSS-G Jobber Drill Bits Boxed1/2 inch HSS Imperial Drills Premium Box Qty-5 - Drillfix


HSS drill bit,HSS drill bits,High speed steel drill bits,steel drilling bits,metal drilling bits,drill bits for metal,drill bits for steel




www.drillfix.co.uk


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## Phil Pascoe (8 Jun 2022)

UK Drills - The on-line choice for Drill Bits, Jig Saw Blades, Cutting Discs and Screwdriver Bits


Choose from over 7,000 professional drill bits online




www.ukdrills.com


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## pgrbff (9 Jun 2022)

Depends on wood or metal bit? I used to get lip and spur from Axminster


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## Phil Pascoe (9 Jun 2022)

It's unlikely he'll use a lip and spur for metalwork.


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## Hawkenwald (9 Jun 2022)

If you or a friend are planning a vacation in USA you'll get imperial sizes over there. 
Maybe not very practical, but you never know......


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## pgrbff (9 Jun 2022)

Phil Pascoe said:


> It's unlikely he'll use a lip and spur for metalwork.


There are projects that use both wood and metal that might be primarily metal.


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## Stevekane (9 Jun 2022)

12.7mm seems to be a common enough size,,and my local bargain bucket shop seems to often get imperial sized bits,, lt sure how or why?
Steve.


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## Phil Pascoe (9 Jun 2022)

pgrbff said:


> There are projects that use both wood and metal that might be primarily metal.


He did post the question in "general metalworking"


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## Vann (9 Jun 2022)

Interesting question. Imperial sized drill bits are still readily available over here (New Zealand), and I'd have thought you guys use imperial measurements more than we do these days.

Cheers, Vann.


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## Spectric (9 Jun 2022)

Having grown up with imperial and pounds/shillings then going through decimalisation and going metric there are now rumours that our circus at the top wants to go back to imperial with pounds and ounces to highlight we are not in the EU. Just having imperial fasteners on American and Canadian wood working tools gives me enough problems without having a bigger mixup on our own doorstep.


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## J-G (9 Jun 2022)

I do wish people would not try to beat the 'circus at the top' with an unwarranted stick!!

The 'proposal' isn't - *and never was* - to 'Return to Imperial measure', it is to remove the _*legal requirement*_ to specify weights and measures primarily in Metric units. It is already legal to use Imperial measures as a 'secondary' piece of information. It will NOT affect the use of metric fasteners.

When Zaire was created (Re-named) from DRC, they insisted that ALL measures MUST be specified in metric terms and would not accept invoices for ' ½" BSP Dies for 3/4" Coventry Diehead ' - That was the stupidity that you are intimating is going to happen - which is simply untrue!


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## Spectric (9 Jun 2022)

J-G said:


> That was the stupidity that you are intimating is going to happen - which is simply untrue!


Nothings imposible with the current bunch of clowns at the top! They need more than a good beating because there is no reason to remove any legal requirement that would allow people to sell in any unit of measurement they fancy, we are now metric and used to what we have, seeing pounds and ounces would be a backward move.


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## J-G (9 Jun 2022)

Spectric said:


> there is no reason to remove any legal requirement that would allow people to sell in any unit of measurement they fancy


I'm sure that Steven Thorburn would disagree!


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## Phil Pascoe (9 Jun 2022)

Thoburn.


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## J-G (9 Jun 2022)

Phil Pascoe said:


> Thoburn.


Oooops! - auto-pilot on


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## J-G (9 Jun 2022)

Spectric said:


> Nothings imposible with the current bunch of clowns at the top! They need more than a good beating


The government may well merit some chastisement but it ought to be on matters of consequence. The issue of Metric / Imperial measures is not one of them and using irrelevant argument devalues and masks the real issues.


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## Sandyn (9 Jun 2022)

J-G said:


> The 'proposal' isn't - *and never was* - to 'Return to Imperial measure',


Darn it!! I had looked out the 1000 8X1" slotted wood screws I kept in the loft. Thought I could sell them on Gumtree. 
I have no idea how I will get rid of the 5000 M10 X 1" bolts!! I saved from a skip


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## ChaiLatte (9 Jun 2022)

Stevekane said:


> 12.7mm seems to be a common enough size



Please pay good attention to this reply. There is very little engineering need today to buy imperial drills. The standard increment for metric drills is 0.1mm, or four thou' in freedom units. Unless you are into doing serious mental gymnastics over letter and number drills, that increment is finer than the standard imperial increment of 1/64" (roughly 16 thou'), so metric drils have four times 'resolution' of imperial.


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## Phil Pascoe (9 Jun 2022)

Which doesn't matter a jot if the OP needs a 1/2" drill.


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## Dalboy (9 Jun 2022)

ChaiLatte said:


> Please pay good attention to this reply. There is very little engineering need today to buy imperial drills. The standard increment for metric drills is 0.1mm, or four thou' in freedom units. Unless you are into doing serious mental gymnastics over letter and number drills, that increment is finer than the standard imperial increment of 1/64" (roughly 16 thou'), so metric drils have four times 'resolution' of imperial.


The plans I am working from only state imperial fractions for hole sizes and also all other measurements are also imperial it is just a pain having to convert to decimal inch measurements. This also includes the reaming sizes


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## Vann (10 Jun 2022)

ChaiLatte said:


> ...The standard increment for metric drills is 0.1mm, or four thou' in freedom units. Unless you are into doing serious mental gymnastics over letter and number drills, that increment is finer than the standard imperial increment of 1/64" (roughly 16 thou'), so metric drils have four times 'resolution' of imperial.


That's all very well, but every 'big shed' here has imperial sizes, however you have to find a specialist supplier (often at specialist prices) for drills in 0.1mm increments.

Cheers, Vann.


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## Kittyhawk (10 Jun 2022)

Well inch/metric drill sizing is a problem for me.
In NZ metric drill sizes in 0.1mm increments will be available in specialized outlets but in general hardware stores metric drills come in 0.5mm increments and they don't stock imperial anymore. I use a lot of small gauge round bar in 1/16" and 1/8" diameter because for some reason small round bar is still sized in imperial. And you can't poke a bit of 1/16" rod in a 1.5mm hole nor a 1/8" into a 3mm hole. We have a big hardware store in my town and it kind of pees me off that I still have to order online, pay courier charges etc to get drill to suit. Why is so much engineering stuff still sized in imperial? This is a continual anguished cry from a lot of metal workers I know.


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## Yorkieguy (10 Jun 2022)

As stated earlier in this thread, Imperial drills are readily available from UK Drills, either individually or in sets. EG a 29-piece boxed set ranging from 1/16th” to 1/2” in 1/64th” steps:









29pc HSS Metal Set


Contains sizes 1/16" - 1/2" increasing in increments of 1/64" For drilling steel, plastic, wood and similar materials.




www.ukdrills.com





Drills from UK Drills are excellent quality in all types at very reasonable prices. I’ve used the company for years. I could also buy imperial drills from a local engineering supplier if I preferred, but not DIY stores.


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## Gordon Tarling (10 Jun 2022)

Tracy Tools have a good selection at reasonable prices. From experience, the service is first class!

G.


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## Spectric (10 Jun 2022)

ChaiLatte said:


> There is very little engineering need today to buy imperial drills


What about letter drills! They may be odd sizes but can give hole sizes that suit different metric fits.


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## ChaiLatte (10 Jun 2022)

Spectric said:


> What about letter drills! They may be odd sizes but can give hole sizes that suit different metric fits.



I did try my best to exclude them (or perhaps treat them as a special case) in my original reply, but that is not reflected in the brevity of your quote.

Nevertheless, what could we usefully say about them?

There is a table of letter and number drills and their measurements in metric here: Drill Size Chart - Machining

In order to put some numbers onto your idea, please go through it and see what the biggest numerical difference is between a letter drill and a 0.1mm increment drill. Please then consider the significance of that difference in the context of the relationship between a drill's quoted diameter and the size of hole it actually drills (https://cdn.mscdirect.com/global/media/pdf/search/dormer/dormer-pramet-drill-tolerances.pdf). In that link Dormer say H12 tolerance, which, even for the smallest size (which is 50% smaller than a letter E drill), is 0.1mm (Tolerances for Holes and Shafts International Standards-APPORO).

Twist drills are not precision items: you can guarantee neither location, diameter, straightness, roundness or surface finish with them.


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## Seascaper (10 Jun 2022)

NickDReed said:


> Hi all,
> 
> Anyone know a good place to purchase imperial drill bits?
> 
> ...


I recently found a large amount of good quality imperial drills at our local car boot sale, many of which had never been used, new in their packets, made in England etc. 50p for the lot so a good find.


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## Spectric (10 Jun 2022)

ChaiLatte said:


> Twist drills are not precision items: you can guarantee neither location, diameter, straightness, roundness or surface finish with them.


If used in a handheld drill then the accuracy may not be precision but you get a hole, used in a drill press with the workpiece fixed down then you get a precise hole providing the drill bit is sharp and suitable for the material being drilled, for real precision then yes you will need a mill.


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## Dalboy (10 Jun 2022)

Spectric said:


> If used in a handheld drill then the accuracy may not be precision but you get a hole, used in a drill press with the workpiece fixed down then you get a precise hole providing the drill bit is sharp and suitable for the material being drilled, for real precision then yes you will need a mill.


If you measure a drilled hole you will find that it will drill slightly over size to get a precise size would mean drilling very slightly under and reaming it


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## Phil Pascoe (10 Jun 2022)

I have metric from 1mm - 10mm in 0.1mms, I also have imperials in odd sizes like 11/32", 25/64" etc. - I find for pen blanks especially it often pays to use the nearest undersized one to the one specified.


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## Vann (11 Jun 2022)

Kittyhawk said:


> ...but in general hardware stores metric drills come in 0.5mm increments and they don't stock imperial anymore...



You've got me worried now. I'll have to go down to Mega and check, but last time I looked (2-3 years ago) they still sold both metric and imperial (I haven't had to buy any recently as they had a good supply at work).



Kittyhawk said:


> ...I use a lot of small gauge round bar in 1/16" and 1/8" diameter because for some reason small round bar is still sized in imperial...





Kittyhawk said:


> ...Why is so much engineering stuff still sized in imperial? This is a continual anguished cry from a lot of metal workers I know.



Nuts. I wanted some 1/4" round bar (to thread 1/4" BSW) two weeks ago and Fletcher Steel said they had none in New Zealand.

I'll send you some imperial drill bits if you send me some imperial rod...

Cheers, Vann.


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## clogs (11 Jun 2022)

Sandyn
if I lived closer I'd be happy to take all those bolts....hahaha....
"one mans meat etc etc"
prob use at least 500 on my next project....


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## sawtooth-9 (11 Jun 2022)

Vann said:


> That's all very well, but every 'big shed' here has imperial sizes, however you have to find a specialist supplier (often at specialist prices) for drills in 0.1mm increments.
> 
> Cheers, Vann.


Yes, getting drills in 0.1 mm increments is more than difficult.
I run with standard metric increments of 0.5 mm, imperial, numbered and letter drills.
Still would like metric increments of 0.1 mm but sourcing these in Aus???


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## sawtooth-9 (11 Jun 2022)

Aus went metric eons ago, but still so many things have odd metric sizes that correspond to imperial dimensions.
If you can't get metric increments of 0.1 mm, then imperial sizes are very useful
I do a lot of work from stainless steel bar - which comes only in imperial sizes from local supply. I work with sizes from 1/8 - 2 inch dia. I usually turn these to metric size, but long shafts etc remain imperial. 
Oh yes, and imperial reamers are a must !


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## woodwind (11 Jun 2022)

All the recommended suppliers are very coy about their P&P charges, I was looking to replace a broken cobalt drill to keep the set complete but will not bother until I really need it, I already have all the drill bits I am likely to need so a £50 or £60 order to qualify for free delivery is unlikely to happen.


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## Kittyhawk (11 Jun 2022)

Vann said:


> You've got me worried now. I'll have to go down to Mega and check, but last time I looked (2-3 years ago) they still sold both metric and imperial (I haven't had to buy any recently as they had a good supply at work).
> 
> 
> 
> ...


We only have a Bumblings here in Whangamata and although they have good stocks of imperial and metric engineering, coach bolts etc there's not an imperial drill bit to be found in the store. Nearest place to source imperial bits would be Bay Engineers but thats in Tauranga, 100 clicks away.
What lengths and material did you want in 1/4" round bar? All that I would have is offcuts in stainless.


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## Stevekane (11 Jun 2022)

Maybe your best bet is buying second hand,,drill bits are often two a penny at boot sales and here at least its easy enough to find imperial and metric,,I guess there is a used marketplace in NZ?
I fear us recommending specialist suppliers in the UK will just prove too expensive for you,,,thinking back I used to sell lots of old junk on ebay and was always happy to post off to exotic places,,a BSA ladies bike to Brazil comes to mind, and I was happy to do it at cost, unlike many new suppliers who seemingly want to charge you for buying from them! Maybe check out ebay private sellers and see if you can find a helpful one?
Steve


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## Sandyn (11 Jun 2022)

Kittyhawk said:


> Why is so much engineering stuff still sized in imperial?


Possibly because the US never fully adopted the metric system?, but having worked for an American company manufacturing in the far east, all drawings were metric.
It is a bit of a mess, but dividing imperial sizes in two is easier than metric.


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## sawtooth-9 (12 Jun 2022)

Aus went metric eons ago, but still so many things have odd metric sizes that correspond to imperial dimensions.
If you can't get metric increments of 0.1 mm, then imperial sizes are very useful
I do a lot of work from stainless steel bar - which comes only in imperial sizes from local supply. I work with sizes from 1/8 - 2 inch dia. I usually turn these to metric size, but long shafts etc remain imperial.
Oh yes, and imperial reamers are a must !


Vann said:


> You've got me worried now. I'll have to go down to Mega and check, but last time I looked (2-3 years ago) they still sold both metric and imperial (I haven't had to buy any recently as they had a good supply at work).
> 
> 
> 
> ...


No problems in getting basic imperial drills in Aus.
Just google Hare and Forbes and you can order over the net. There are plenty of other sources here on line.
For really " difficult stuff, you can google Mick Moyle - in Sydney. His website is very poor, but if you email him - you can really get some "hard to find" stuff.
Stainless bar is no real problem here ( up tp 2 inch ). !/8, 3/16,1/4,5/16'3/8,1/2, 5/8, 3/4, 1,1.5,2 inch
Depending on the quantity, I could buy and ship to you if you really run into trouble. Suspect postage cost would be high though !


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## Richard_C (12 Jun 2022)

I don't have a strong view of allowing imperial unit selling, and there is nothing to stop it happening now as long as a metric unit is on the pack/scales alongside imperial. It does seem to be a bit of unnecessary blue passport populism, we could do that before Brexit too, like Denmark.

2 things concern me. One is that to do business in the wider world its useful to use the units they do (the USA recognised that a long time ago for some industries) but the main concern for consumers is sneaky shrinkflation. A half pound of butter looks like a 250gm pack until you get it home, but I doubt the retail price will shrink by 9%. I buy coffee beans, a few years back they were 250gm bags, now they are 227. Clearly marked so not illegal but it took me a while to spot it. One supermarket did it so they all had to follow suit or they look expensive. It strikes me that the change might be an opportunity for corporate sneakiness. 

Back to drill bits. A friend was clearing his deceased father's garage, father had lived in USA for a few years. He gave me an index box of brand new hss bits, shiny and still covered with protective oil. All the 64ths from 1 up to half an inch. Really nice, and I have used a few sizes recently in "fixing things" jobs. There are days when only a 23/64th will do.  (and yes, I know you can get 0.1mm increments but how many of us have them in the drill bit cupboard)


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## J-G (12 Jun 2022)

Richard_C said:


> 2 things concern me. One is that to do business in the wider world its useful to use the units they do (the USA recognised that a long time ago for some industries) but the main concern for consumers is sneaky shrinkflation. A half pound of butter looks like a 250gm pack until you get it home, but I doubt the retail price will shrink by 9%. I buy coffee beans, a few years back they were 250gm bags, now they are 227. Clearly marked so not illegal but it took me a while to spot it. One supermarket did it so they all had to follow suit or they look expensive. It strikes me that the change might be an opportunity for corporate sneakiness.


On a similar tack - Cadbury's chocolate bars 200g -- well they were! 2 for £3 since it my habit to take one 'row' of squares from a bar at any one time - and never more than once a day - I quickly realised that Cadbury had changed their molds so that a 'row' was now only 4 squares not 5. Checking the wrapper, what do I find ? They've reduced the weight to 180g !! that's a sneeky 11% price hike.


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## Spectric (12 Jun 2022)

sawtooth-9 said:


> Aus went metric eons ago,


So why does Triton still use 1/4 unc in it's routers?


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## Spectric (12 Jun 2022)

Us older folks really feel robbed because we can remember the sizes of many things and can see how they have shrunk, you used to get a packet of crisp but now you just get a sample but at much greater expense, most confectionary has shrunk several times so now they are in minature and things like wagon wheels are not fit for a go kart. With many items the packaging is used to disguise the small volume of contents, with some boxes you need a torch to see what is in there because the air space is so cavenous.


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## Richard_C (12 Jun 2022)

Spectric said:


> So why does Triton still use 1/4 unc in it's routers


It's a low volume product. Maybe once upon a time a trainee in the purchasing office, keen to impress, saw that he could get a better price if he bought 250,000 components all at once. When they run out, estimated sometime late this century, they will go metric. Or its a strategic decision, they won't have to change back when in a year or few our new King and JRM force the commonwealth to readopt hogsheads, furlongs and ancient thread sizes. 2BA or not 2BA, that is the question.

(going on a bit I know, tested very faint + and definite - for C19 this am and although I feel fine aside from gloom and lethargy, the responsible version of me is treating it as an asymptomatic positive. So I have little to do, missing a live CBSO concert right now)


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