Lay down insert threading tools

[Mayhem]

I arrived home today to find my latest tool purchase had arrived.

   

   

This is a Carmex SIR 0025 R22 internal threading bar, which takes 22mm inserts. The bar is 25mm diameter x 200mm long. I have purchased this especially to make internal threads to match the 6tpi spindle on my lathe.

After discussing my needs and options with PixMan, I was not going to go this route, as inserts in this size cost more and it is more economical to use the 16mm inserts which cover 8 - 40 tpi and are cheaper. However, I picked this up off eBay for under $40 AUD. I have ordered two 22IR 6UN BMA ($13.75 ea), which should last me a while.

Having cut an external 7/8" x 14 thread using a ER16 insert at PixMan's Dad's shop I was sold on them. The finish is excellent. Whilst I have an external HSS threading tool, I would have to buy a HSS boring bar (would you believe my only boring bar is a 5/8" SCLCR bar that I found!) to cut internal threads.

[EdK]

You must have one big lathe to be able to use a 1" shank threading tool on it. What lathe do you have?

Ed

[Mayhem]

(03-29-2012, 06:48 AM)EdAK Wrote: You must have one big lathe to be able to use a 1" shank threading tool on it. What lathe do you have?

Well that is the $64,000,000 question Ed. To be honest I have no idea as to who made her or when. 36" swing over the gap, 18" over the ways and 60" length. I have a CA size QCTP. Check post #16

Now you know why my signature reads the way it does!

[EdK]

(03-29-2012, 07:39 AM)Mayhem Wrote:

(03-29-2012, 06:48 AM)EdAK Wrote: You must have one big lathe to be able to use a 1" shank threading tool on it. What lathe do you have?

Well that is the $64,000,000 question Ed. To be honest I have no idea as to who made her or when. 36" swing over the gap, 18" over the ways and 60" length. I have a CA size QCTP. Check post #16

Now you know why my signature reads the way it does!

That is a big one. Nice job on the restore.

Ed

[DaveH]

Mayhem,

I'm stuck on the first word

What does a "Lay down insert ........." mean?


DaveH

[Mayhem]

It is one of three configurations of threading inserts. I don't know all of the details of each but you can read more about them here http://www.doriantool.com/doriantool/index.php

One bonus is that I can go from a UN thread to a metric one or an ACME or buttress thread just by changing the insert (and possibly the anvil). Hopefully PixMan will stop by this thread and help out with the technicalities.

[PixMan]

Far be it for me to tell another man that he has a nice tool, but....

That's one helluva nice threading bar and I envy you that. I'm limited to just the ER/IR 16 size inserts for now. I can envision adding the larger 22's when the right tool appears on Ebay for the right price.

DaveH, if there's anything you wish to know about the triangular lay-down threading inserts I'm happy to help. I will tell you this: It can be expensive to get into them, and you have to weight the cost-benefit ratio for your own situation. The benefits include beautiful, perfectly ISO/ANSI-compliant threads (when using full-form pitch-specific inserts), and reliable performance.

Apart from the pitch-specific full-form (a.k.a. "cresting") inserts, there are A60/AG60/G60 "partial profile" inserts that are capable of making threads of a wide range of pitch, though the sacrifice is that they have a .002" (A60 & AG60) or .007" (G60) tip radius and they don't create the thread height themselves as the full-form ones do. The A60 or AG60 are the ones to have no matter what, so you're not stuck not being able to make a thread if you don't have the perfect cresting insert on hand.

That should be enough to generate questions!

Ken

[DaveH]

Hi Ken,

It is the term "lay down" I had't come across before. I'm still not sure what it means.

DaveH

[ETC57]

Ya know one of these days I'm gona catch up to you guys,

between all the numbers and terms I've never heard of and all the tools I still don't have you guy's keep me hopping that's for sure!!(LOL)

Just keep at it, caus I am

Jerry.

[Mayhem]

Thanks Ken. That was an eBay purchase from a seller in Israel.

I could be wrong Dave but I think it is because you have to go and have a lay down and a cup of tea to cope with the excitement you experience by the threads you produce.

I had to turn a 5/8 x 11 thread today and whilst I did it fine with a HSS bit, the results were nowhere near as good. Here is the 7/8 x 14 thread that I cut using PixMan's full form lay down insert. That is how the insert cut the thread. There was no filing or other cleaning once it was cut.