Thread: Ifanger Threading Tool - Replacement Cutter Height Adjustment Screw - Suitable Steel?

The threading tool is the smallest Ifanger made and by the looks of it, possibly a superseded model. The height of the cutter is adjustable by means of a small screw engaging a section of "thread" machined into the side of the cutter. Current catalogue images do not show the screw adjuster.

A couple of days ago I was using the tool to cut a 9 TPI, 0.071" deep thread in some 1214. Shouldn't have be a big deal but there was a BANG and the cutter slid downwards in the holder. I think I had not tightened the nut securing the blade retention wedge sufficiently and sadly the little adjustment screw bore the brunt of the bang, losing a portion of thread.

I need to make a new screw. The screw is 7mm in diameter and the thread has a pitch of 1.75mm. The tooth has an included angle of 30 degrees. I do have some Stubbs 8mm diameter silver steel along with ample 4140. I don't know whether the screw should be hardened. The original looks like it was given the break. Any suggestions regarding the appropriateness of what I have or recommendations for something more suitable?

Bob.

I'm not really qualified to give you any sort of definitive answer Bob, but I would think that 4140 would be more suitable than silver steel. 4140 would be tougher, while silver steel can be hardened to a harder state I think than 4140 can, it would likely be too brittle, or make that more brittle than 4140 would be. Silver steel would be better as the cutter than 4140, but for the screw I think that 4140 would be the better of these two. Even an unbrako shcs would be good enough I imagine if you had one big enough to cut your screw from. Good luck,
Rob.

4140 Bob. If you do choose to use silver steel make sure you anneal it well. I've broken a silver steel screw I made. I can't for the life of me remember what it was for, but I do recall not annealing it and it broke some time later.

Edit: I remember now, it was part of an indicator holder

Thanks for solving a long time puzzle of mine, i have quite a quantity of the blades? For this but i didnt know what the holder looked like or who the manufacturer was.

Originally Posted by caskwarrior

Thanks for solving a long time puzzle of mine, i have quite a quantity of the blades? For this but i didnt know what the holder looked like or who the manufacturer was.

Cask,

The Swiss modified the clamping method to ensure a positive lock of the cutter by incorporating serrations on the cutter and wedge. The photos are of Alan"C-47"'s larger 2K threading tool. I rang MTI Qualos, the Australian Ifanger distributor, this morning just to make sure they didn't have a box of replacement screws gathering dust on a shelf. They didn't and none of the threading tools they sell have adjustment screws.

What size are your cutters and are they smooth or serrated?

BT

I cant tell you the sizes offhand unfortunately, but mine are definitely serrated, I see you posted a photo of your screw, unfortunately i dont have one in with my box of mystery ifanger bits.

Have a look from here onwards - //metalworkforums.com/f65/t1712...91#post1857191
there are a few around.
Perhaps I should send you mine Bob - it might fit your Hercus...

Michael

Originally Posted by Michael G

Have a look from here onwards - //metalworkforums.com/f65/t1712...91#post1857191
there are a few around.
Perhaps I should send you mine Bob - it might fit your Hercus...

Michael

Thanks Michael but it's probably way too big for the bitty Hercus. The tool post's holders will accommodate 16mm high tooling, useful on a larger lathe than my 9", but I can only use 12mm high tools.

Bob.

I used 4140. The finish appears OK to the naked eye but blown up it looks like a rasp was the tool of choice.

I cut the screw slot a whisker deeper than I wanted on screw no.1 so I made no.2. I have no idea why the saw blade cooked the screw 2 since it cut the previous screw slot nicely. It was only a 1.4mm deep x 3.75mm wide cut? The heating of the steel seems to have hardened it. I had trouble filing it with a brand new triangular needle file.

Anyway, apart from the appearance, the screw works as it should. I will just make sure the wedge is tight and I know where the spare is hidden!

The final photo shows that hen's teeth do sometimes make an appearance. Ken "Toggy" had sent over a box of jeweller's gear for my daughter a few weeks ago. In the box was a small Moore and Wright micrometer cardboard carton containing a number of punches for gold and silver marking and an Ifanger size OK 55 degree cutter without the newer version serrations. Never did I think that I would ever find one!!

Thank you Ken.

BT

It was a pleasure BT. I had remembered that you had an Ifanger holder, just not sure of size. At least it has gone to a good home. If things had of gone the other way here; the wife and kids would have just dumped the lot at the scrappies. They have no idea or appreciation of quality or precision tools and equipment.

It is hard to believe that it is 4 weeks today as of this very moment.

Ken

Originally Posted by Anorak Bob

I used 4140. The finish appears OK to the naked eye but blown up it looks like a rasp was the tool of choice.

Nice job Bob. For the finish try a higher speed and coolant, even if the latter comes out of a hand held spray bottle or similar. You may have trouble getting a high enough speed with such a small diameter.

Thanks Pete.

The speed was limited to how fast I could crank the spindle by hand, my usual method for cutting metric threads and others to a shoulder. A long laborious process given the coarse thread, the slenderness of the stem ( which became the screw's head ) behind the thread and the fear of bending and ruination if I was too heavy handed. Probably forty passes to cut the 60 thou and at the end I was cutting less than a thou a pass. Thread cutting fluid was used liberally and I reckon the only thing that warmed up was my left arm!

Bob.

Sorry Bob, I thought you were referring to the finish on the stem. It appears it's tearing and the limit is most likely the top speed of the lathe.

I've found 4140 finishes best with coolant as cutting fluid would be too smokey at the required speeds. When cutting threads other factors come in to play, as you mentioned.