Jig for hand tapping

Hi, I made one from an old drilling machine and it's good for small taps, this is for drilling and tapping small parts and has a 0 to 4mm chuck fitted in this photo Drill. Tapping can be done using the knurled section of the driven pulley and the belt can be slipped off and a bar used in one of the six holes underneath if need be. There is a wright up of it in MEW 238.

Regards Nick.

Edited By Nicholas Farr on 17/07/2020 20:25:46

Nick, I love the lantique / vintage ook of your jjig...beautiful. To a tapping greenhorn I am scared stiff of either tapping on the lathe or with a motor on a jig. It's the loss of control whereas by hand you can stop at any point. I will one day when I've eaten my weetabix have a go on the lathe. Meanwhile I am buying in a cheapish drill press and going for it.

Regards

Chris

You don't need to have the motor running on the lathe or you mill to use it for guiding the tap, not much point in buying a drill press for it when you have a perfectly capable mill.

Hi Chris, I don't use the motor for tapping and is really intended for small and delicate work, I bought this drill at a steam engine rally several years ago for only about a fiver I think and it was in a sorry state with bits missing, I had in mind to refurbish it, but could not find any illustrations or info about it, so decided to make it what it is now. As JasonB says you can used a mill to do the same thing without using the motor. A photo of it as bought Old Drill

Regards Nick.

Nice buy Nick nice job to.

H

Jason, well you may well be right. However I am playing it safe until my skill and knowledge builds on the mill. I can see from your photograph that using the mill you can guide the tap. My issue , ney worry is screwing down the mill whilst rotating it. At the moment it seems more complicated / risky than the hand jig, Hence my decision. With your more experienced eye you have a better idea. I do take on board spring loading the tap but there are issues of having taps with holes and enough shank to allow the tap holder to grip. At the end of the day I take a view and certainly I can't always be right but that's life. I respect every post that is helpful but as always there is a spectrum of advice and genuinly greatly appreciated.

regards

Chris

Forgive the slight digression [‘though I am actually returning to the title of this thread] ...

Someone on the microbehunter forum was pictured using this drill & tap guide, patented by Bruce P. Rooney and currently available in the USA

I think it worth sharing:

**LINK**

https://patents.google.com/patent/US7131796

and also this, for a related version:

**LINK**

https://patents.google.com/patent/US9751133B2/en

MichaelG

There's no need to overthink stuff. I use a sprung guide with either male point or female dimple to guide the tap and within the sizes I need it works fine into the back of the tap holder. If using really small taps then something like this:

link

with a parallel shank into a tube held in the mill chuck and use gravity obviates any need for delicate quill movement. Easy enough to add a torsion bar to the the shank.
Any system that involves moving the part to another machine risks losing registration.

pgk

You can most certainly use Taps or Dies in the lathe. You don't have to run under power.

Make a mandrel handle and turn it by hand. You have full control and can feel how much torque is being applied.

Recently, I tapped some 5 x 0.5 mm holes, 3.5 mm deep, by just pulling the chuck round by hand.

If you are tapping in a vertical mill, or a drill press, the outer end of the tap should be guided by a spring loaded guide, and you will be able to judge the torque applied, by hand.

Among various Tapping aids, I made a free running chuck, with handles, to fit in my Mill/drill, but the quill needs tom be followed down to avoid overlaoding small and fine threads.

My preference is to use a sliding Tap or Die holder, mounted in the Tailstock of the lathe. My home made Sliding tap holder uses ER 25 collets,, but a drill chuck would work just as well. ME 40 threads don't like dragging a Tailstock along the bed!

Howard

Chris, while it would be easier with a quill feed on your mill it is not needed. In the first photo I posted where I said just nip the chuck up the tap is free to move vertically but restricted sideways so it will just pull itself into the work with a bit of gentle downwards pressure.

The sprung guides mentioned by several others will also keep the tap guided as it progresses into the work as the spring takes up the gap. A sprung guide with a conical hole on the end will take care of your taps with no hole in the end which given the small sizes you are likely to use will be most of them.

If you are prepared to do a project that will do away with issues of "is my tap square"?, then you cannot do any better than invest in some time and effort to build George Thomas Universal Pillar Tool.

A superb bit of kit, I now rarely need to tap with a tap wrench and have never needed to use the mill or drill in an effort to keep the tap upright.

Regards

Derek

Or if you don't want such a lengthy project that would be too big to make on your machines anyway how about a smaller version using your mill as the basis here

That’s neat, Jason

Great for drilling, and adaptable to tapping.

MichaelG.

I have used these guides on small shafts and sides of bosses and have yet to break a tap (down to 10BA).

Start the thread immediately after drilling hole using a centre to guide the tap and thread. Once the tap has started, move the part with tap to a small machine vice on the bench. Place the guide over the tap shaft and sit it square on the top faces of the vice jaws. Grip the shaft in the vice and finish tapping.

Obviously this would be difficult with the pulley illustrated.

An Eclipse tap wrench is not my preferred tool for small taps. I made a nice little brass wrench that you can use between finger and thumb.

JA

Edited By JA on 18/07/2020 08:36:15

Michael, yes I found something similar and for most situations as far as I see it might well do the job. The only issue I had using this was tapping holes on tubes. I did find this :

https://www.youtube.com/watch?v=Yv0p6Jb0sIk

which is using a V block but its all a bit messy and not universal.

Chris

Jason, love this and have noted all for a future project.

Chris

Derek, I agree I am aiming at building a jig based on the George Thomas Universal Pillar Tool. Seems not a lot of work, as always there are alternatives some better but this looks good to go.

Chris

.

Strangely enough ... the big feature of Mr. Rooney’s device is the Vee groove on the underside:

.

MichaelG.

Chris Tick-Tock,

Three jars in your chuck ???? Really, what is this forum coming to ? Bad enough to have three jars in the pub, and then have to find your way home !

PS Why dont they make keyboard letters BIGGER ???

Some years back there was a design in MEW for a tapping & staking tool using cast plumbing components in place of castings - struck me as quite ingenious at the time. However I do most of my tapping in the mill under power using the VFD or if in the end of a bar in the lathe (not under power), or occasionally by hand. I think the trouble is that in the old great days of model engineering designs like the Universal Pillar Tool were published by the likes of George Thomas and everyone assumed that that was the proper way to do the job, but as pointed out in this thread once you have a bench drill or vertical mill you can find ways to use it for tapping. Why spend time making a complicated tool that isn't really needed?

I thought it was obvious, but no you don't try to old the driving square of the tap in the chuck jaws, you hold the cylindrical shank.