Thread Rolling

[Adam HarrisParticipant @adamharris13683]

Yes a ridiculous amount of money. I agree , best to buy a pair of the correct sized dies on fleabay and put them on a home made knurling tool. I am asking about the procedure for using the Fette head because I happen to have a couple and want to try it for fun. I intend to sell them afterwards (I see them offered on fleabay for £600-£1000!) and if needed would proceed along this DIY path

[David Clark 13Participant @davidclark13]

Hi Adam Free sliding. I think we just came up to the start of the bar and it fed itself down.q

[Adam HarrisParticipant @adamharris13683]

Many thanks David. I will set it up accordingly. Earlier in this post it was mentioned that one needed a fairly powerful machine to do thread rolling – in your opinion is the 3/4hp Myford Super 7 too puny?

[David Clark 13Participant @davidclark13]

It might be capable especially with smaller threads. I don't think there was any strain on the motors we used. Certainly the motor did not slow down or change its noise.

[Ian S CParticipant @iansc]

You could use back gear if you don't think there is enough torque in the higher gears.

Ian S C

[Adam HarrisParticipant @adamharris13683]

For anyone who is interested in the speed and power required for thread rolling, Fette advise that an M8 thread can be rolled with a 1/2 hp machine at 30m/min for mild steel – therefore setting the Myford lathe belts at 1200rpm should be fine for rolling an M8 thread. In terms of procedure, mount the head on a free sliding carriage or tailstock or capstan, set your carriage/tailstock/capstan stop at the point you want the dies to disengage/open, and then apply CONTINUOUS manual force on the carriage to slide the head onto the workpiece and rapidly all the way to the stop. The intent is to keep slight manual sliding pressure on the head ONLY in order to keep up with the fast threading movement. This is merely to prevent the threading pull from triggering the disengage spring before the stop is hit. The disengage spring is too sensitive to allow the threading process to pull the head/carriage along on its own. Larger thread rolling heads have less sensitive disengage springs that may allow the threading to pull the carriage/capstan/tailstock along on its own without manual assistance.

[Involute CurveParticipant @involutecurve]

Posted by Michael Cox 1 on 21/09/2015 18:19:58:

I have often thought about trying to make a simple tool for thread forming. In essence it would be a little like a conventional scissor type knurling tool but with the rollers threaded at the required pitch. It would be used like a knurling tool but with the leadscrew engaged and change gears to suit the required pitch. Has anyone seen or made such a tool?

Mike

I looked at this scissor method and will come back to it at some point, my thoughts where, to have three rollers, one lateraly fixed and the other two floating by about half pitch, I figured as the thread formed the two floating rollers would fall into line as it where.

[robjon44Participant @robjon44]

Adam, I have sent you a PM

[Ady1Participant @ady1]

It looks like an evolved/advanced type of knurling to me, very clever

[jason udallParticipant @jasonudall57142]

..looks like evolved/advanced type of knurling…

Yeah at say 1mm depth…but yes similar process. Generally with “milder” -less sharp- profile..

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