Using a friction clutched tapping head for threading bolts/studs etc.

Hi All
I have a Coventry die head but this doesn’t work well on short threaded studs or bolts, due to the fact it needs to pull its self forward out of its main body by 3/4mm to disengage.
To aid threading under power I decided to machine a die stock which fitted in to an Archer friction tapping head as can be seen in the first photo.
With the clutch set correctly on the tapping head, it is possible to machine right up to a shoulder or the chuck jaws under power without fear of snapping of the screw or pulling the job out the chuck or damaging anything for that matter. Having a positive stop/datum aids length tolerance repeatability, of the thread being cut. I have added a link to some bolts I made for my 1” scale Minnie traction engine in bronze using the tapping head setup.
This is a link also to my split die setup which saves a lot of time and effort http://www.homemadetools.net/forum/s...ie-setup-65783

Attachment 21549Attachment 21548Attachment 21550Attachment 21551

Link to minnie traction engine cylinder block bolts Practical Engineering

Again thank you for taking the time to view my post
The Home Engineer

Very nice if the torque is adjustable1

Hi Frank
There is a friction clutch in the back of the unit which can be easily set by tightening the castle nut with the c spanner to compress the friction pads. Once you come up against a shoulder etc. If set correctly the chuck simply over comes the drive friction and spins. I have several tapping chucks and in my opinion the Archers are the best.
The Home Engineer

Thank you. The only tapping chuck I remember ever having was a 1" tap-matic with a 40 CT taper

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Thanks thehomeengineer! We've added your Clutched Tapping Head to our Tapping and Threading category,
as well as to your builder page: thehomeengineer's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-clutched-tapping-head"> <img src="/uploads/209234/homemade-clutched-tapping-head.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-clutched-tapping-head">Clutched Tapping Head</a> <span> by <a href="http://www.homemadetools.net/builder/thehomeengineer">thehomeengineer</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/tapping'>tapping</a> </div> </div> </div> </div>
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