|Cornish Jack||20/08/2018 18:28:11|
|868 forum posts|
This is the product of trying to drill a hole in work-hardened steel with a Fobco Star - the 'thinned' point being produced by thermal distortion and the shape by crap manufacture!!
|David Standing 1||20/08/2018 18:28:20|
|1193 forum posts|
Hah, you did it deliberately then
|David Standing 1||20/08/2018 18:42:28|
|1193 forum posts|
Pretty much all of my drills are bought secondhand as job lots off eBay.
Yes, you get some junk amongst them, but I mainly get lucky and only buy the quality stuff, old Dormer (pre Brazil), Guehring, Balfour, Sherwood, SKF, Easicut, Presto etc.
You invariably get duplicates, but I have made up a number of full sets of metric, fractions, number and letter drills in stands, and have lots of spares.
They invariably work out a fraction (pardon pun) of the cost of new ones.
|Trevor Crossman 1||20/08/2018 19:21:45|
|125 forum posts|
THAT looks more like an old fashioned stick of liquorice rather than a drill. I have broken many drills over the decades, but have never been able to bend one that much !!
618 forum posts
Joined the Air Force at 17 and became an Aircraft Technician (Airframes), when carrying out airframe repairs majority of rivets were 1/8” and we very soon learnt that accurate holes were paramount and also drills needed to be sharp. One of our acquired skills was being able to hand sharpen our drills, not able to do it now, the advancing years and the wearing of varifocals mean it’s no longer achievable. As an aside varifocals can be so frustrating when you are trying to unscrew or do up small screws in awkward places where you can’t get your head in the right position.
|62 forum posts|
I also use UK drills on ebay and haven't had a problems as Larry says they seem to be cheap and carry a good range with quick delivery, https://www.ebay.co.uk/str/UKDRILLS?_trksid=p2047675.l2563
|Ian P||20/08/2018 21:18:30|
2050 forum posts
For one job the customer ordered and bought an expensive high quality German 16.4mm drill that had been sharpened for anticlockwise rotation.
|Andrew Johnston||20/08/2018 21:33:39|
4498 forum posts
Oh dear, people never seem to learn. There is no point in buying cheap tooling, even if it isn't complete junk it may have other problems.
Rule 1: Never buy cheap tooling
Rule 2: see rule 1
Many years agoI coughed up and bought imperial, letter, 1-6mm by 0.1mm and 6-10mm by 0.1mm drill sets by Dormer. I think I got them from Greenwood Tools at a big discount on the RRP. Fairly expensive but they last and last. Over 10 years or more I've replaced a couple of dozen. None of the letter drills, one imperial drill because I fudged it on stainless steel, and several metric drills because they wore out, or I damaged the drill or shank. The metric drills are by far and away the most used. The imperial drills are conventional and the metric drills are 4-facet ground. I doubt I'll need to replace the imperial drills in my lifetime. Holes are accurate; I measured a 6mm drilled hole and it was between 1 and 2 thou oversize. The metric drills measure spot on over the cutting edges, as far as I can tell, but the shanks are 1 to 2 thou undersize, ie, they're ground on a slight taper. Presumably that's for clearance.
I can grind drills by hand or on the Clarkson, but simply can't be bothered, the smaller Dormer drills are fairly cheap, and for a few a year it's down in the noise.
I buy special drills as required from Drill Service in Horley. They're mostly slow spiral for brass, left hand for the repetition lathe and carbide for difficult materials like tungsten.
I've got a good selection of larger drills, up to 1-3/4" for use on the lathe to rip metal before boring. They're all secondhand, mostly from Ebay. I don't care if they're odd sizes, like 1-1/64", or drill slightly oversize as long as they drill a hole!
I've also got a set of number drills by Presto that I bought over 40 years, but I use the 1-60 number drills once in a blue moon.
Edited By Andrew Johnston on 20/08/2018 21:35:23
3402 forum posts
I've bought a couple of sets of drills from Tracy Tools and been very pleased with all of them. Top product at a good price. Wouldn't waste my life away on the cheap junk.
|Neil Wyatt||22/08/2018 18:01:50|
15707 forum posts
By way of evidence I refer the Court to this thread:
1140 forum posts
Which seems to suggest that buying "decent" drills doesn't always work either. Was that your point, Neil?
|Mike Poole||22/08/2018 18:33:09|
1814 forum posts
Well I did did say someone would have a duff Dormer and sure enough
|Neil Wyatt||22/08/2018 20:12:54|
15707 forum posts
My point is that drills are produced in huge quantities so even the 'quality' brands have to check batches on a sample basis and some rogues will get through.
I greatly doubt that 100% checking of 'economy' price drills is either practical or could be done with little impact on price.
|973 forum posts|
A couple of the quality producers ie Hertel and Titex for definate actually make left hand drills, check the part code.
Jack i have seen very similar a few times with what appears to be a soft finished steel unwinding. All 3 times the drills look very poor with little or no grinding and cheapo.
A decent set of drills ie older Hertel 1-6mm x 0.1mm and 6-10mm x 0.1mm steel cased would have set you back circa £115 shopping around 13 years ago.
I do tend to try as much as i can out by trial and error not just a proper brand name but each type of drill they do. Will find some are better suited to the type of work you intend doing.
|431 forum posts|
I bought a set of drills, I believe of Chinese origin, from Tracy tools. All the cutting edges are perfectly sharp and cut well. However some of the larger sizes are slightly bent, and the leading edges of the spiral flutes are as sharp as razors. This gives the the ability to cut sideways like an end mill. this results in the bent ones cutting well oversize. When I say they are sharp, I have on several occasions cut my fingers on them getting them out of the box. To be fair, Tracy tools offered to change them, but I felt that was unfair as It had been a few months since I bought them.
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