Countersinks

[jasonB]

just dont seem to be one that will do all think to all materials

I did say that "I use the 3 flute Ruko ones in metal AND THEY WORK WELL IN WOOD"

Screwfix do a few of them But J&L keep a better range including a full set for £282 + VAT :shock:

Its best to use the virtual cataloge when looking for stuff from J&L countersinks start on page 122

Jason

 

[Vann]

...no one can say for sure wether it's any good with metal as well...

I used them when working as a sheetmetalworker 10 years ago. Mainly used countersinking 3mm mild steel sheet, and they worked really well !! I thought they were only for steel !! After reading this thread I'm going to get myself one or two for wood.

The ones we used on sheetmetal were 'Sutton" brand (a good quality Australian brand). Cheap ones might not handle steel so well.

Cheers, Vann.

 

[Jonthepom]

A top tip when countersinking metal to stop "chatter" shown to me years ago by an old craftsman, was to fold up a piece of rag waste to form a pad of about 8 thicknesses and approx 1" square,place over the hole to be countersunk and using a rose bit or a twist drill, sharpened to 90deg proceed to drill through the cloth,quite a bit of pressure is needed to start the cut but a clean, chatter free countersink is produced.Current heath and safety police would certainly disaprove but it sure worked for me.

 

[ike]

I've had reason to experiment with different countersinks recently having had a job to countersink a total of over 25,000 holes in ABS!

Previously I've only used a snail type (Axminster) - v.good on timber but prone to clogging occasionally.

I got a HSS 5-flute (Hall) - superb on metals and an HSS 3-flute (Hall) - good on timber but not as smooth as a snail type, excellent on plastics similarly softer materials.

No single type is 'best'. Each type is best suited to certain materials, generally according to hardness. One thing I did find out - Axminster are v. expensive - like twice as much as the local engineering supplies company.
Ike

 

[GraemeD]

Since Axminster say in the catalogue that the Halls Snail countersink can be used on metals, I merrily used mine on mild steel, brass and aluminium as well as wood.

It did work really well, but after some use it seemed to become dulled, and less effective. Worried I'd done something wrong....or had a duff one....I wrote to Halls to ask what was happening.

They fully checked it over, and their conclusion was that I should have used cutting paste when cutting metals, and that was the only reason it has lost its edge. They were kind enough to replace it free of charge, but I am now under strict instruction to use paste when cutting metals!

They actually said that the softer metals are the worst....they said Aluminim and Brass should never be countersunk without cutting paste....Steel is ok occasionally without. Not what you'd have thought. Axminster also do the paste....only costs £2.99 for a bottle, so if it makes the difference, it must be worth a go. I'm not one for spending on unnecessary consumables, but I've since used it and cut a lot more countersinks in mild steel and my cutter still looks as good as new.

Hope that helps!
Graeme

 

[Oryxdesign]

No one else has mentioned this so maybe it's me. I find that the snail type of countersink sometimes does not register concentric with the drilled hole. I still use them though as they give a good finish and fast cut, generally once the screw is fitted that lack of concentricity doesn't show.

 

[GraemeD]

I must say I have notice that too! When it happened in a cordless drill, I was prepared to believe it was due to the drill being slightly off 90 degrees to the work, but it does it just as much in the pillar drill. Not a problem in metal....but it does it in wood, definitely!

Graeme

 

[head clansman]

hi ike


you were not wrong about the snail countersinks being expensive at axminster , i couldn't believe the price when shown where they were in the shop at axminster today.

I went there to buy two mobile machine bases, a bevel box , & some sanding sheets plus other bits as well , when you concider the amount of metal in the machine bases plus the work that go's into making the wheels brkt nut bolts etc for £34, then the assistant opens the cabinet :lol: :lol: :lol: and hold up three from large - small quoting for large £48 i missed the price of the middle one from shock and just caught the last price for the small one at £16 bearing in mind the small countersink is about 9mm by about 25mm in length a small amount of steel against the mobile machine base size what go's wrong when manufactures products are priced for sale :?:. :? :? #-o mind boggling o yea needless to say I'll source the countersinks else where .

.hc

 

[Aled Dafis]

Another vote for using lubricant. :wink: :lol:

Using lubricant means that your edges will stay sharp longer, produce less heat, and the surface finish will be greatly improved. In fact there's no real reason not to use it.

I teach engineering at a secondary school, and a bottle like this lasts us about two months. A little really does go a long way, the cost spread over the number of holes you get out of a bottle is negligible.

http://www.mscjlindustrial.co.uk/ACL-01483H/SEARCH:KEYWORD/product.html

Since insisting that my students use lubricant for every hole they drill/tap, the number of broken drills/taps has also decreased dramatically, and I spend less time at the grinder resharpening drills. As I mentioned above, there's no reason not to use it.

Cheers

Aled