A Use for that Cheap Tap Set

[Neil WyattModerator @neilwyatt]

Let's be honest, we all own a cheap and cheerful carbon-steel metric one tap per thread set bought twenty to thirty years ago and used (if we are generous) several times before we ran up the white flag and bought a decent set.

In a flash of genius, i have realised that such a set is worth putting to one side especially tor finishing off threads in 3D prints. Small threads in plastic or larger ones partially printed in don't pace any challenges as cheap tape can't cope with

Neil

[Neil WyattModerator @neilwyatt]

[Anonymous]

Agreed that being brittle doesn't matter, but being blunt and the wrong size might. This is what I do with cheap taps and dies before binning them and never buying from the supplier again:

Andrew

[Mick B1Participant @mickb1]

Posted by Neil Wyatt on 08/10/2017 21:11:10:

Let's be honest, we all own a cheap and cheerful carbon-steel metric one tap per thread set bought twenty to thirty years ago and used (if we are generous) several times before we ran up the white flag and bought a decent set.

Neil

Well, it's got 2 taps and 1 die per thread and I had to grind the pointless point off the plug taps to make 'em any good for blind holes, but my cheap and cheerful set worked well for me for 15 years, so I bought another a few months back. I use it all the time on silver steel, brass, phosphor bronze, alli and titanium (that squeaks a bit sometimes), but I've not broken any and the old set only started blunting in the last year. They may not be suitable for long runs, but the cheapies aren't all rubbish.

[I.M. OUTAHEREParticipant @i-m-outahere]

I use mine for cleaning out threads on engines , machines etc as it saves blunting a good tap .

[Nick HulmeParticipant @nickhulme30114]

I use cheap tools for giving to people without any tools

[Neil WyattModerator @neilwyatt]

Posted by XD 351 on 08/10/2017 22:50:54:

I use mine for cleaning out threads on engines , machines etc as it saves blunting a good tap .

Ditto

[Andy CarruthersParticipant @andycarruthers33275]

If I could be a little contentious here…

How does one know what "good" looks like? price is no guarantee of quality

For the occasional use mine get – and paradoxically I actually managed to get out into the workshop yesterday and actually tapped an M3 hole – a cheap set is probably sufficient, until they break, blunt, are proven to be the wrong size

Whilst I am learning it doesn't make a lot of sense to spend a fortune on quality tools – yet…

[MWParticipant @mw27036]

Posted by Andy Carruthers on 09/10/2017 13:48:20:

If I could be a little contentious here…

How does one know what "good" looks like? price is no guarantee of quality

Whilst I am learning it doesn't make a lot of sense to spend a fortune on quality tools – yet…

I don't think that's contentious at all, You're simply asking for proof that something is worth it. That's the $64M question.

[Andrew TinsleyParticipant @andrewtinsley63637]

Hello Neil,

I have been very happy with my cheapo carbon steel taps. The set I got, had 3 taps per thread and were very sharp. They cut as well as expensive HSS taps and only now, after maybe 20 years, are one or two showing signs of bluntness. They have been used quite often and I am really amazed at how good they have been!

I seem to break expensive HSS taps, but up until now, touch wood, I have never broken a carbon steel tap. Probably amateur's luck. I would guess that cost per hole tapped is less for carbon steel than HSS. So carbon steel taps are not all bad!

Andrew.

[Enough!Participant @enough]

Posted by Neil Wyatt on 08/10/2017 21:11:10:

Small threads in plastic or larger ones partially printed in don't pace any challenges as cheap tape can't cope with

I don't usually bother with taps for small holes. Just print the (plain) hole then run the screw in and let it form its own thread.

[SillyOldDufferModerator @sillyoldduffer]

My oldest set of taps and dies are Japanese made BA; not good even when brand-new circa 1968. I should throw them away.

Recent purchases of inexpensive taps and dies have been much more successful. I've had good use out of them and don't expect them to last forever.

However, my most recent purchase – £4.99 from Aldi – did have faults. The 4mm tap snapped like a carrot and the 10mm die was blunt. Strangely the rest of the set is fine.

One reason for buying quality tools is that they are more consistent. This is a valuable feature when time is money, probably less so for a hobbyist. My risky £4.99 set wouldn't be acceptable in professional hands. As it is, I spent £4.99, found two duds, and the rest are good. In my amateur hands the set is a bargain.

Andy mentioned that 'price is no guarantee of quality'. Very true. Buying too expensive is every bit as bad as buying too cheap. Really we should all be after 'value for money'. That means having some notion of what you mean by 'fit for purpose' and how long you expect the item last. If value for money turns out to be Asian, that's fine. If it turns out to be a new Myford Connoisseur, that's fine too. What's not fine is buying stuff just because it's reassuringly expensive.

Dave

[Neil WyattModerator @neilwyatt]

Posted by Andrew Tinsley on 09/10/2017 15:21:02:

So carbon steel taps are not all bad!

I have some nice and some gorgeous carbon steel taps. I did say "a cheap and cheerful carbon-steel metric one tap per thread set"

The distinguishing characteristic (aside from a dull finish) of these sets is that each size only has one tap.

Neil

[Howard LewisParticipant @howardlewis46836]

The problem with almost any tap is that it breaks in the last hole in the job.

Certainly holds true for many of the carbon steel ones that I've used.

As said, buying good quality is expensive, and not cost effective for most of the work that we do. But to my mind cheaper, and less frustrating, than having to remake the piece all over again, just as I thought that it was coming close to completion.

Howard

[Nick HulmeParticipant @nickhulme30114]

Posted by Howard Lewis on 09/10/2017 19:18:33:

The problem with almost any tap is that it breaks in the last hole in the job.

I haven't had a tap break since I started actively deciding the % of full thread to cut and using an appropriate drill size, add a to that a quality lubricant and assuming decent tooling and you'll feel when the tap is losing it's edge before you break it.

Andy's question is interesting, my solution is that "Good" looks like the tools I buy from reputable suppliers, should there ever be a Lemon in the bunch I can take it back, show them what's wrong and get a replacement or a refund

– Nick

[jimmy bParticipant @jimmyb]

Posted by Andrew Johnston on 08/10/2017 21:33:22:

Agreed that being brittle doesn't matter, but being blunt and the wrong size might. This is what I do with cheap taps and dies before binning them and never buying from the supplier again:

Andrew

wise move!

Once I decide a tap is no good, I run them across the off hand grinder…

[roy entwistleParticipant @royentwistle24699]

I have quite a few carbon taps and dies ( all British ) of some vintage and down to 12 BA I have never broken one yet

I really like carbon lathe tools, though I wouldn't consider carbon drills

When you think about it files are usually carbon

Roy

Edited By roy entwistle on 10/10/2017 11:14:58

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