Jig for hand tapping

[BazyleParticipant @bazyle]

Just had this idea. Will it fly?
What have you just done before you tap a hole? Drill tapping size of course.
So how about some short bars drilled axially half way throught to take the tap, then finished all the way through with the tapping drill. Put in a cross hole at the right point to take a screwed in tommy bar to both grip the square on the tap, hold it in, and act as the thing to grip and rotate. Make one for every taper tap.
Then when you drill the tapping hole leave the the drill in, put the above tap holder over the drill and it is perfectly aligned but rotates and slides along as needed. I agree there is a clearance issue so you have to remember to start with enough gap between chuck and work.
The second and bottoming tap have threads to follow so shouldn't need a guide.

[Nigel Graham 2Participant @nigelgraham2]

When I worked for a company making precision screen-printing machines, the millers had made themselves their own versions of that ROFMILL device, using three pieces of BMS bar screwed together, in place of that casting. Holding the device horizontally (as in the lower photo) in a bench-vice, and the work in one hand, they could tap several holes in mild-steel or aluminium-alloy piece-parts at quite smart rates.

At home I generally use the bench-drill to start the tap, rotating it by hand.

Paul raises an interesting question – "general trend to [replace] 'traditional' methods [with] more modern" alternatives.

Surely what counts is not whether something is called "traditional" but whether it is the better choice for the situation, user, cost, time, etc.? Really, the conjunction of the words "traditional" and "modern" are relevant only in a history-book, but unfortunately often conflated in the same way as "progress" and "improvement" or "up-date / up-grade". They are not synonyms.

Obviously no-one would seriously consider replacing the electric motor on a modern lathe with Grandad's old foot-motor (except perhaps to save also buying a running-machine!) but what of the lathe itself? In its basic form, it is the most "traditional" of machine-tools and all the details are developments made over very many years.

Similarly, many model-engineers now choose to buy laser-cut plate-parts, or at least mill them to profile; rather than chain-drilling and filing them – but as easier and more accurate methods, rather than modernity alone.

So yes, a tapping-head would be the ideal alternative to a tapping & staking tool for many applications, but by no means all; and it is not unreasonable to have both it and other tools available for greater flexibility, given the range of tasks we perform.

The choices we make in our workshops should be based on technical and practical reasoning, not simply artificial conceptions of old and new, or someone's idea of "traditional".

I first encountered that word as a sneer in a strange "New" Maths side-syllabus, at school in the 1960s. Though it did introduce old concepts starting to find real-world applications, like Binary Arithmetic, in later years I realised the maths it derided as "traditional" was the maths actually used professionally by scientists and engineers. Similarly with workshop tools and techniques: describing them as "traditional" or "modern" does not really help.

By all means let it be modern and better, but they mean different things and it is the latter adjective that is important.

[HopperParticipant @hopper]

As we live in the post-modern world, modern methods are old hat already anyway.

Much of the change in workshop practices today comes down to price and availability. In G H Thomas's day, cheap hobby mills and tapping heads and even drill presses were not available so he made his own pillar tool for fine drilling, tapping etc. Others made do with the traditional steel block with a hole drilled in it to guide the tap. Or just did it by eye with a try square for guidance.

These days we can click on a website and a purpose built tapping stand or small mill or drill press and tapping head arrives shortly at our door at not very great expense.

People fear the hobby is dying out but judging from the phenomenal amount of such once-exotic workshop kit now available everywhere , there must be more demand than ever for it.

[derek hall 1Participant @derekhall1]

Hi guys

I built the George Thomas UPT for the sheer pleasure of making a tool that could hold taps square down 12ba without breaking them, use it with the drilling attachment and now have just made the attachment for clock bushing.

It's a tool that is truly universal and a superb design, looks good and of course designed by one of the "masters".

I enjoy making well designed tools, some may not like making tools to make tools others see making a tool or jig as getting in the way of the latest project or model, each to their own of course!

But I made the UPT as I saw it as the long term solution to non square tapped holes and made the basic tool many years ago. I would not be without it…

Kind regards to all

Derek

[HopperParticipant @hopper]

Here's an example of what I mentioned: LINK

$A86 that's about 43 quid, for a purpose built small tapping stand. I would struggle to buy the material and drill chuck to make one myself for that price.

MicroMark make a similar one, but with a vice included, costing about ten quid more.

That's the difference between traditional methods and today's. You can just send out and get this stuff delivered, whereas years ago it was either not available or was hideously expensive, plus you had to write away for a catalogue, wait for it to arrive, send back an order form and a postal money order purchased from the local post office, and then wait interminably for the money to clear and then the slow boat to bring your item. Meantime, you wouild have just drilled a hole in a block of scrap steel to guide the tap and be done with it.

[Chris TickTockParticipant @christicktock]

Posted by Nigel Graham 2 on 21/07/2020 01:15:31:

Surely what counts is not whether something is called "traditional" but whether it is the better choice for the situation, user, cost, time, etc.? Really, the conjunction of the words "traditional" and "modern" are relevant only in a history-book, but unfortunately often conflated in the same way as "progress" and "improvement" or "up-date / up-grade". They are not synonyms.

I think this is a really well considered post. The only caveat could be that if someone sets out only to use traditional repair techniques then so be it. But let's not fight over different approaches, especially if it's one man in his shed pursuing his hobby. Some folk (myself included), just like making stuff, it occupies my time in a pleasant, constructive way until I eventually fall off my perch hopefully not though for many years.

Still takes considerable time mastering the different machinery and that's not to mention a fair wedge of money and time. The craft / hobby will live on as long as us humans in turn on the wider spectrum understand the need for radical change (sorry a tad too far…getting political).

Chris

Edited By Chris TickTock on 21/07/2020 08:50:13

Edited By Chris TickTock on 21/07/2020 08:54:09

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