Tap alignment in the mill and lathe?

[Bo’sunParticipant @bosun58570]

Good morning,

I have many taps that are devoid of either a cone or point on their tail ends.  This makes using a spring loaded tap aligning tool out of the question.  Plus, even if small taps have a point, the tool plunger can obscure the tap wrench square.

A tapping chuck sounds like a good idea, but the hard tap shanks and chuck jaws can limit grip.

A ‘T’ style tap wrench with a centre also seems a good idea, but after watching Joe Pie’s video about said tool, that’s not a reliable method.

My most successful approach has been to loosely clamp the tap in a 3 jaw chuck, with a small flat ground on the tap shank to secure a tap wrench.  I’m not keen on the idea, but it does seem to work.

Any thoughts?  I’m sure there has to be a better way, or am I missing the obvious.

[EmgeeParticipant @emgee]

I use the method you describe but release the jaws so they only act as a guide:

My most successful approach has been to loosely clamp the tap in a 3 jaw chuck, with a small flat ground on the tap shank to secure a tap wrench. I’m not keen on the idea, but it does seem to work.

 

Emgee

[BazyleParticipant @bazyle]

Simply putting paper between jaws and tap increases grip but select the paper type, ie not glossy magazine.
I once set out to make discs with a square hole to fit in my sliding die holder but gave up after filing the first one which of course I have now lost.

[JasonBModerator @jasonb]

I Put the tap wrench onto the round shank then the square is not obstructed. Bonus is it will slip if the tap goes tight and may save a breakage

A bit of silversteel with a Ctr drilled hole will locate pointed and chamfered and even square ends. A point on the other end will guide taps that have a ctr hole

Leave the tailstock unclamped and just push against the handle to keep pressure on the tap. In the mill light quill pressure is all that is needed.

One I did about 20 mins ago

[Bo’sun]

On 2 November 2024 at 09:07 Bo’sun Said:

Good morning,

I have many taps that are devoid of either a cone or point on their tail ends.  This makes using a spring loaded tap aligning tool out of the question.  Plus, even if small taps have a point, the tool plunger can obscure the tap wrench square…

Eeek, I’ve obviously been lucky in that all my taps came with a cone or point. Are Bosun’s machine taps, not intended for hand use?   So I can avoid buying plain ones by mistake, who sells them?

I’d be inclined to grind points on the end of all the small ones.  Cones more difficult, perhaps a Dremel with a pointy grinding tip?

If the tool-plunger obscures the flat, not difficult to make one that doesn’t.   Assuming you have the time!  It’s just a spring loaded plunger in a tube.  This is mine, home-made.

Dave

 

 

[SillyOldDuffer]

On SillyOldDuffer Said:

On 2 November 2024 at 09:07 Bo’sun Said:

Good morning,

I have many taps that are devoid of either a cone or point on their tail ends.  This makes using a spring loaded tap aligning tool out of the question.  Plus, even if small taps have a point, the tool plunger can obscure the tap wrench square…

Eeek, I’ve obviously been lucky in that all my taps came with a cone or point. Are Bosun’s machine taps, not intended for hand use?   So I can avoid buying plain ones by mistake, who sells them?

I’d be inclined to grind points on the end of all the small ones.  Cones more difficult, perhaps a Dremel with a pointy grinding tip?

If the tool-plunger obscures the flat, not difficult to make one that doesn’t.   Assuming you have the time!  It’s just a spring loaded plunger in a tube.  This is mine, home-made.

Dave

 

 

Yes agreed. I must have over 100 taps and they all have cones or points.

[Bill PhinnParticipant @billphinn90025]

Bosun isn’t the first to be stymied by this:

Using a tapping guide with taps not designed for one

Seeking slim-nosed spring tapping guide/follower

[JasonBModerator @jasonb]

Dave, machine taps have square ends with a mix of points, chamfer sor just the edges eased, That is a machine tap in my photo. That is why they make special collets for them with a square hole at the end to ensure they do not slip and lose registration with the spindle when “rigid tapping”

I thought there may be comments about the end of taps so took this when I went back into the workshop, quite a range of ends and all will locate with that simple bit of silver steel. I think I must have used the two that I have for over 50 engines.

[SillyOldDuffer]

On SillyOldDuffer Said:

On 2 November 2024 at 09:07 Bo’sun Said:

Good morning,

I have many taps that are devoid of either a cone or point on their tail ends.  This makes using a spring loaded tap aligning tool out of the question.  Plus, even if small taps have a point, the tool plunger can obscure the tap wrench square…

Eeek, I’ve obviously been lucky in that all my taps came with a cone or point. Are Bosun’s machine taps, not intended for hand use?   So I can avoid buying plain ones by mistake, who sells them?

I’d be inclined to grind points on the end of all the small ones.  Cones more difficult, perhaps a Dremel with a pointy grinding tip?

If the tool-plunger obscures the flat, not difficult to make one that doesn’t.   Assuming you have the time!  It’s just a spring loaded plunger in a tube.  This is mine, home-made.

Dave

My general tap collection does contain a variety of end shapes, but recently I bought a selection of eleven ME taps from an established supplier (often recommended on this forum), and they all had flat/slightly domed ends.

 

 

[VicParticipant @vic]

I’d grind the end. Some of mine just have a chamfer but it’s more than enough to use a tapping guide, at least in the sizes I use.

[peak4Participant @peak4]

1/4″ or 3/8″ drive tap sockets work OK, but only for a fixed range of sizes, use with a hex ended drill adaptor etc.
For example only, plenty of other sources, prices, and sizes
https://www.lasertools.co.uk/Product/6058/Tap-Socket-Set-3-8-inch-drive-1-4-inch-drive-8pc

Also I find the old Crown style 2 jaw chucks give a good grip on taps; I’ve yet to find one, but apparently they are also available to take square bars/shanks; They are still in production, at a price, though not common; mine are likely older than me. Unlike many keyless drill chucks, they are fine anti-clockwise

Maybe also a Morse tapered ER collet chuck, or even a keyless drill chuck intended for battery hand drills, as they work in both directions, and seem to have a finer thread behind the jaws, which gives a tighter grip.

Bill

[egaParticipant @ega]

I use and recommend the Vertex tap chuck which grips on the square and aligns on the round shank.

[John PurdyParticipant @johnpurdy78347]

This is what I use. Standard “T” handle tap wrench modified by removing the handle and any dedent ball and spring then silver soldering the handle back in and drilling an 1/8″ hole up through the body. The tap is chucked in the holder and the short 1/8″ rod is held in the tail stock chuck ( or the milling machine chuck) and the tap wrench is slid on to it, thus ensuring that the tap is aligned with the hole in the work. The larger one will hold taps up to 1/4″ the smaller one #0 up to #10 (.060″ – 3/16″). The smaller one was bought in Woolworth’s 5 and 10 back in the mid ’50s when I was a very young teenager, probably for about 5 cents and is still going strong!

John

[VicParticipant @vic]

The video mentioned in the OP. Luckily I very rarely used this technique anyway. 😉

https://youtu.be/C0PBPGjd0Pc?si=ZXp6Ln0j05Y751pO

 

[Neil LickfoldParticipant @neillickfold44316]

I have pins that have each end, the diameter of the tap flats. They are kind of an industry standard to fit the tapping heads. I lift the tap wrench to have about 1mm above the top of the tap. The round diameter fits against the tap wrench flats and guides the tap. Works for the lathe or the mill.

On larger taps, I grip them in the chuck, usually with the 1st taper tap, and get the thread started either running slow, 100 rpm or so. With the Spiral flute taps in the mill, I have what is called a cnc keyless chuck. Irony is , it comes with a pair of spanners for loosening the chuck. They do up by hand, and have a very thin areas that grips the shank of what ever you are holding. Allows for power tapping down into a hole and to reverse out again. I use 100rpm for power tapping lathe or mill.

Small taps, like M3 and smaller, I power tap with the small sensitive drilling attachment. I have a few from different places. Arc have a nice one with a key chuck, and also from Little machine shop. I also made my own version with a wider key slot and larger pin with a flat on it. It has a lot longer stroke than the standard ones. It has a 60mm stroke for drilling small holes to 55mm deep. I can tap M4 with that one. The body was made from 4340, and the inner shaft is turned down from the shank of a long M10 cap screw. It has the JT0 Arc small drill chuck. Has a home wound spring (0.3mm music wire) in the 3/16 drilled hole of the sliding shaft.

Neil

[Bazyle]

On Bazyle Said:

Simply putting paper between jaws and tap increases grip but select the paper type, ie not glossy magazine.

Thanks Bazyle.  That makes me wonder if material from an aluminium drinks can will do the same?

If it does, that means more beer.  What a shame.  Not in the workshop of course!

[Clive FosterParticipant @clivefoster55965]

These days I just power tap in the Bridgeport at low speed and be done with it. Tap held in three jaw chuck, not too tight with the baby ones, and finger hovering over the stop button. If its a blind hole stop short and finish by hand.

Sharp tap in a hole well anointed with Trefolux of course. Machine taps if I have them, hand taps if not. Preferably serial versions of the hand taps to reduce forces.

Realistically 6 mm is about the limit for holding direct in a 3 jaw. But I have the full range of Pollard tapping heads for big stuff.

Buttocks tightly clenched first time with a 2.5 mm! But if Mr Pollard says the No 200 tapping head can go down to 1.5 mm …..

I really must find a source for the collets used in the no 200 as I only have one.

Before I worked up the courage to power tap small I used to grip the tap in the chuck and turn the chuck body by hand with the machine in neutral whilst applying down-feed. Quickly discovered that the tap would slip in the 10 mm chuck rather than snap if it stopped cutting.

Clive

[Dave SParticipant @daves59043]

If I’m drilling in the mill I tend to just whack in the appropriate sized ER collet, tighten it up and then turn the spindle by hand (or spanner for larger sizes), using the quill to feed. This is generally m4-m10 or so. Smaller than that I have a center that fits a 6mm coller and a tiny Moore and Wright tap handle with a female centre in the back – that’s used for the under m4 sizes – down to under 1mm.

If the part isn’t drilled on the mill, such as by hand then I’ll usually power tap with the battery drill, I don’t often do “freehand” drilling for tiny holes, so this is typically M5 upto M10

Dave

[John HaineParticipant @johnhaine32865]

I tap under power on the mill when I can using the dro for alignment.  Haven’t broken a tap yet.  Great advantage of vfd, run the spindle very slow and instant reverse

[mgnbukParticipant @mgnbuk]

The “Archer” tapping chuck has separtate adjustments for centering the tap shank & gripping the drive square plus, maybe, a friction overload clutch.

The front knurled nut is a 3 jaw collet that doesn’t drive the tap, just centres it – the cone under the nut that the collet jaws run in is a steep taper to give rapid size adjustment but no gripping power. The two cylinders nearer the shank ( prevented from rotating by the two small screws running in slots in the cylinders, but free to slide side-to-side ) slide in a common cross bore & are joined by a stud threaded LH one side & RH the other & using the square ended key in the stud adjusts the gap between the cylinders to grip the square. The collar with a notch just below the shank has 4 slots across it’s face & I think this is the friction overload clutch force setting ring.

On the rather scabby example I have this adjuster ring has proved impossible to move with a C spanner, but shows damage to the edges of the slots suggesting it has been hammered up very tight. (the picture above came from an Ebay listing & isn’t of my chuck). Mine ia also larger & on a 2MT shank, with the jaws applicable to maybe M6-M10 size range taps.

Nigel B.

[bernard towersParticipant @bernardtowers37738]

Yes the 4 slotted nut is the clutch adjuster. the clutch is paxolin washers with interspersed steel washers with drive tags. work well when set up but thats what takes the time.

[Howard LewisParticipant @howardlewis46836]

I made up an arbor to fit into the tailstock, on which slides (loosely) a shop made body for ER collets.

The body is tapped for an anti rotation bar, (Which rests against the Toolpost) and the collets grip tightly enough to drive the Tap (Depending on how tightly you clamp it) so that if there is a jam ujp, the Tap slips in the collet, avoiding a broken Tap and scrap workpiece.

The loose fit, body to arbor, allows the Tap (or Die, if Die Holders are used) to self centre, so it pays to put a slight chamfer on the leading edge of the job.

Since the new thread has only to overcome the slight frictional load of the loose body on the arbor, there is minimal risk of stripping the new thread. (Even ME40 threads survive and they are only 0.016″ (0.4106 mm) deep). Recently 8 BA holes were tapped, under power, using this kit, so it seems quite safe.

Howard

[Bo’sunParticipant @bosun58570]

Thank you Howard, I’ll look into making something utilizing ER collets as they will grip the tap much better than a Jacobs style chuck.

[bernard towersParticipant @bernardtowers37738]

If your going to go the er route why not get the er tapping collets they are quite reasonable in 16 size

[Bo’sunParticipant @bosun58570]

Thanks Bernard, that’s certainly an avenue worth exploring.  They’re new to me.  Oh well, as they say, “another school day”.

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