Tapping in a straight line

[WolfieParticipant @wolfie]

[WolfieParticipant @wolfie]

OK heres another one thats being a pain. On my journey to build my first steam engine, I have had to remake parts on more than one occasion because the threads aren’t straight!

 

In other words the tap or die hasn’t gone in or on at a right angle.

 

Now I know with a bit of bar you can put it in the lathe chuck and do it that way, but what about things that are irregular or don’t fit in the chuck?

[keithmartParticipant @keithmart]

Hi

The simplest way is to use a piece of bar with a hole down the middle, face off to be at right angles to the hole which should be a tight clearance for the tap you are using.

Use it as a tapping jig.

regards

Keith

Leeds UK

[JasonBModerator @jasonb]

The other method is to leave the work in the vice after you have drilled the tapping hole and use the drill chuck to guide the tap. If the tap has a centre hole in the end use a bit of rod with a point in to locate in the hole or loosly grip the tap with the drill chuck and turn the tap using a tapwrench on the round shank of the tap.

 

As for threading with a die, just keep checking the handles on teh die stock are horizontal as you cut the thread.

 

J

[TomfileryParticipant @tomfilery]

Wolfie,

 

At the risk of committing heresey – I take Jason’s method a stage further and put the tap in the drill chuck and turn the chuck by hand (NOTE – NOT under power), whilst pulling down on the feed handle (gently). Once the tap has started to bite, it pulls itself in.

 

Ok – you have to be careful with very small taps (and this wouldn’t work for ones bigger than about M5), but you are only aiming to get it started straight. After a few turns, undo the chuck, remove the work from the vice and complete by hand. Obviously, if you are drilling and tapping a series of holes, you have to do one, extract the tap and then move onto the next.

 

 

Regards Tom

[Harold Hall 1Participant @haroldhall1]

For the external thread, have a look at

 

 

http://www.homews.co.uk/page304a.html 

 

 

Harold

Edited By Harold Hall 1 on 25/09/2011 21:15:35

[TerrydParticipant @terryd72465]

Hi Wolfie,

 

Here’s a link to a tapping guide which sort of shows teh principle. The guide is placed over the hole to be tapped and it aligns the tap to the hole. A homemade one is perfectly adequate. If necessary you could clamp the guide in place once it is initially aligned:-

 

http://littlemachineshop.com/products/product_view.php?ProductID=3427

 

The following spring loaded and inexpensive device is used in conjunction with a mill/drill or lathe to centre the tap and some pressure on the initial cuts. You can use a normal tap wrench to turn the tap. You can use a drilling machine, mill or lathe fitted with a faceplate to support the workpiece even with awkwardly shaped components and tap guide. See it here:-

 

http://www.chronos.ltd.uk/acatalog/Tapping-Guide.html#a318221 

 

Regards

 

Terry

Edited By Terryd on 25/09/2011 21:36:30

[WolfieParticipant @wolfie]

Thank you to all oracles, I have lots to go on now

[JESParticipant @jes]

I have been informed by google that the site linked to Machinist’s Tap Wrench Can ifect your computer with Malware.

 

JES

[blowlampParticipant @blowlamp]

Something like this is very useful too http://www.arceurotrade.co.uk/Catalogue/Cutting-Tools/Hand-Tapping-Fixture

 

You can make a similar contraption from a modified portable drill stand.

 

 

Martin.

[wheeltapperParticipant @wheeltapper]

Like this.

cheers

Roy

[TerrydParticipant @terryd72465]

Posted by John Stannard on 26/09/2011 08:21:28:

I have been informed by google that the site linked to Machinist’s Tap Wrench Can ifect your computer with Malware.

 

JES

 

Hi JES,

 

I had no problem with the using either Firefox or Google Chrome.

 

Regards

 

Terry

[Gone AwayParticipant @goneaway]

Posted by John Stannard on 26/09/2011 08:21:28:

I have been informed by google that the site linked to Machinist’s Tap Wrench Can ifect your computer with Malware.

Yes, I’m getting that today too (Firefox). It was fine yesterday when I looked it up and my Sunday evening full-virus scan went off without a hitch. It’s just a regular tool suppliers site that happened to have an example of the tap wrench I was describing.

 

Here’s another reference site if you are interested:

 

Reichel Tap Wrench

 

I also use it when tapping in the lathe.

 

Perhaps DC/Diane could remove the original link or post?

Edited By Sid Herbage on 26/09/2011 17:15:30

Edited By Sid Herbage on 26/09/2011 17:19:01

[Diane CarneyModerator @dianecarney30678]

Previous post removed.

Happy to be of service.

 

Diane

[ViKARLLParticipant @vikarll]

Hi,

Just to add my two cents worth.

For the most common drill taps I use, (i.e. 6, 8, 10 for mm and ¼, 3/8, ½ for Inch sizes) I have a long-nut each, welded to a plate at one end. I simply align & clamp the plate to the work piece and tap along the existing thread. After two or three turns are tapped, I remove the contraption and continue as usual.

It goes without saying that your plates should be welded to the long-nuts perfectly perpendicular. Also, you have to ensure sufficient pressure on the tap wrench as you start the cut so as to not let the guide nut threads take the brunt.

Hope this helps ….

[Lawrie Alush-JaggsParticipant @lawriealush-jaggs50843]

Jeez Roy, what happened to your workshop? Where is the crud?

[wheeltapperParticipant @wheeltapper]

Haha, the tapping jig is standing on the freezer,its more than my lifes worth to mess that up.

 

you don’t want to see the bench, come to think of it, its quite a time since I saw the bench.

 

Roy.

[Steve WanParticipant @stevewan33894]

Hi Guys

 

I learnt a trick to tap using a small bench press with the spring coil removed. I saw a Japanese website did this way using an old press drill without the motor.

 

I re-invented this idea using a workable bench press to pre-tap the hole once the tap bite sufficiently, I continue the rest on a table vise. Then of course with the motor off and belt removed by rotating the pulley by hand.

 

Tapping on the lathe is suitable for bigger lathe not Sherline or Unimate.

 

So any form can be tap easily as long it has a flat base and sides for clamping. This way one save the money buying a tapping press and save space for other essential machine for small workshop.

 

Steve

[Author]

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