My preference is for HSS, even if not used frequently.. I have an ability to break carbon steel!

HQS is T & D version of HSS, NOT carbon, hence the price being higher than carbon steel..

T & D supply industry (As I am sure that Tracy do ) so cannot afford to supply rubbish.

Have had good service from both firms.

Howard

MY experience is most far east manufactured carbon steel taps these days are not of the best quality, but I haven't bought from Tracys.

Tony

Edited By Tony Pratt 1 on 11/09/2022 15:40:38

As for taps the ones I reach for the most are spiral flute, YG-1 for models and ARC for general work, jigs etc You really only need one of these not the usual set of three and they can be turned by hand not just machine.

Edited By JasonB on 11/09/2022 16:12:56

Often a tap breaks because it is being bent.

There are ways to avoid this.

The hole should be the correct size for the thread being cut. If in doubt, a tiny bit oversize is safer than undersize. Zeus Charts give the correct size drill to use, and the nearest stick size, for this reason.

A very slightly oversize drill will mot decrease the % thread engagement ruinously.

The simple way is to make and use a Tap guide. Just a piece of metal drilled and tapped with the thread to be cut in the work, so that the tap is held square to the surface of the work.

If a hole has to be tapped in an inclined surface, a flat surface (such a spot face ) on which the drill and Tap can be used.

Use a Tapping Fixture (Mine is based on a stand for a pistol drill, but with the tap being held in a small drill chuck, and rotated by a short tommy bar.

In a lathe, Taps and Dies held in holders which slides on an arbor held in the Tailstock. In this way the Tap or Die is on the axis of the lathe, and the newly cut thread is subjected to the mimimum load, rather than trying to drag a Tailstock along the bed.

In a Mill My preference is for a spring loaded holder to guide the outer end of the Tap, whilst it is driven by a suitable sizes tap Wrench.

Suitably lubricated, backed off every half turn, and kept clear of swarf, breakage should be a are occurrence.

Trefolex, Rocol RTD are suitable lubricants for Tapping. Bacon fat will also suffice, if the need arises.

Obviously when using a Die the workpiece should be he correct size for the thread being cut.

HTH

Howard

I believe that HQS is carbon steel and don’t really feel that is does the Tap and Die company a great service to use the mysterious term. However I have found their HQS taps and dies to be made to a high standard and fit for purpose. I feel that carbon steel has acquired a poor reputation as it has been used by the economy end of the market to produce a poor quality tool. HSS is a more expensive material and more difficult to machine. I suspect that HSS is machined by grinding in its hardened condition and so by default is a ground thread rather than a cut as often offered in carbon steel. Reading of peoples problems with threading it would seem that poor quality HSS taps and dies can be found from some sources which together with inexperienced users create real trouble for some. The great attraction of HSS was that it could hold an edge even at red heat whereas carbon steel is very easily destroyed by overheating, overheating is unlikely to be an issue with normal tapping methods but HSS does seem to be more durable and keep an edge longer than carbon steel and is first choice production work or probably more exotic material these days. It probably matters more to buy a decent quality tap rather than what it is made from but as HSS is more difficult to machine and a more expensive material it was once more likely that HSS would be the best option. Buying a brand with a good reputation or from a supplier with a sound reputation should rule out the tool being at fault and take a good look at the technique being used, if it is tried and tested then revisit the tool.

Mike

Edited By Mike Poole on 11/09/2022 20:06:39

.

Thanks for that, Mike

I suppose the root of the problem is that the term ‘carbon steel’ is itself almost meaningless

MichaelG.

.

[quote]

Carbon Steel

Carbon steel is composed of iron and 0.12 – 2.00 percent carbon. The broader definition includes alloy steels, which can also contain up to 10.5 percent alloy content. Even within the confines of under two percentage points of carbon, there is huge variance in physical characteristics—especially hardness.

When people talk about carbon steel, they are usually referring to the high carbon steel used in knives and tools. High carbon steels are very hard, which makes them good at resisting abrasion and retaining shape. They can withstand significant force before deforming. Unfortunately, hard metals are also brittle: when placed under extreme tensile stress, high carbon steels are more likely to crack than bend.

Low carbon steels are more common than high carbon because of (1) lower production costs, (2) greater ductility, and (3) ease of use in manufacturing. Low carbon steels tend to deform under stress instead of breaking, and that ductility makes low carbon steels easy to machine and weld. They are frequently used in automobile body panels, bolts, fixtures, seamless tubes, and steel plate.

[/quote]

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Ref. __ https://www.reliance-foundry.com/blog/carbon-steel-versus-stainless-steel

Edited By Michael Gilligan on 11/09/2022 21:16:36

I agree Michael, the term carbon steel tells us nothing other than it is steel and not iron. A tap needs to be made from a high carbon steel but again high carbon steel only slightly narrows the range of possible materials, other elements can be added to improve a simple high carbon steel for the making of taps and I am sure that the actual specification was carefully chosen by manufacturers before HSS was widely used. I think carbon steel is a generalisation to identify it is not a HSS, with some of the junk standard items it may be wishful thinking that it is a properly selected and heat treated high carbon steel which over the years has made people wary of non HSS taps and dies. I remember my father telling me that turners on piecework would actually buy their own HSS toolbits as they were supplied with high carbon steel, they covered the cost by being able to use higher speeds and heavier cuts with a reduced resharpening requirement, I suppose the company finally realised they were behind the times and adopted HSS toolbits.

Mike

HSS where easily available and affordable.

For 'obsolete' threads like ME and BA I have carbon sets, although i woudl buy HSS if replacing any broken BA taps as they are available.

Also I have carbon taps and die plates for really tiny treads as they are ridiculously cheap and can be treated as disposable, being only used for very rare jobs.

Neil

For the interest of the members I have just done a spark test on a HQS tap from Tap and Die, a typical display as produced by high carbon steel and very different from the HSS tap I used as a control. I am confident that HQS is a high carbon steel, I am also quite happy that it is a good tap that is fit for purpose although I may choose something else if I was buying for a high volume production use.

Mike

Am I to understand that the Tap and Die Company don't actually sell HSS taps, and that all of their taps are made of "HQS"?

If that is the case, I hope I'm not being overly cynical in tentatively concluding that they're selling what are essentially carbon steel taps (good ones, maybe) whilst trying to claim they're in a special qualitative category that puts them (implausibly, in my view) above more expensive HSS taps.

I've not actually checked that their HQS taps are cheaper than typical HSS taps, but I assume from Peak4's quoted blurb on the first page of this thread that they are.

Edited By Bill Phinn on 12/09/2022 17:56:08