Any recommendations for an interior insertable threading tool?

[Mirage_Man]

I just broke my last insert for my inside Thinbit threading tool. Rather than ordering more inserts for it I am thinking about trying a different tool. I have seen several different types i.e. lay-down, on-edge etc... I was hoping you guys would share your experience and preferences for this type of tool. Specific brands, models and sizes would certainly help.

Most of the threading I'm doing is either 20tpi or 32tpi and mostly Aleph/E-series compatible parts in titanium as you might have guessed. I would of course like some room to work but the smallest bore will be around .762". I like to get as close to the inside shoulder as I can too.

I think that covers it but if there's anything I didn't mention let me know.

So what do you recommend?

 

[PhotonFanatic]

Brian,

I presume you are only cutting right hand threads, most likely by feeding the tool holder/insert toward the headstock, which would be rotating counterclockwise.

If getting close to an interior shoulder is of paramount importance, then you need to consider cutting the threads by outfeeding the tool holder and insert, while the spindle is rotating clockwise. To do that, you will need to use left hand tools and left hand inserts.

While there are many very good brands out there, I'm partial to Sanvik. They make some great carbide threading bars and carbide inserts to go with them. And now that you're cranking out those high-priced Ti pieces, you can afford them

Sorry, but I'm not able to supply exact part numbers and sizes. I would just suggest that you call your local Sandvik distributor and tell them what you want to do.

 

[Anglepoise]

I have been very happy with ThinBit inserts and for the sort of work we all do, hard to beat. Priced right and very good quality.

 

[Mirage_Man]

I have been very happy with ThinBit inserts and for the sort of work we all do, hard to beat. Priced right and very good quality.

I use many of their stuff too. It's just that @ $16 an insert with only one cutting edge it can get expensive when you break them. I was hoping one of the types with 3 cutting edges might work just as well.

 

[fludunlimited]

this is the one I was told to get
http://www.jlindustrial.com/KTH-48759C/SEARCH:MFR/product.html#

I havent ordered one yet but plan to in a week or so.

 

[Anglepoise]

As PhotonFanatic says,Sandvik make some very nice stuff.
But its also pretty pricey. I use one of their boring bars with a triangular insert. I know they make 60° insets as well but you have to buy they 12 at a time that also is expensive. I have a small copper diamond impregnated lap and use this to sharpen all my carbide.

Do you snap your threading inserts often?

 

[precisionworks]

The triangles are nice, and you do get 3x the life per insert ... but ... each insert size cuts only one tpi size. Some manufacturers state otherwise, but watch out. That may or may not be a problem for what you want to do.

In a Carmex insert, 20tpi is 16 IR 20 UN. The inscribed circle is 3/8".

The 32tpi is 16 IR 32 UN.

Most likely, their T20 coating is the one for Ti, but phone or email first. Their website, carmex dot com, lists toolholders also.

 

[wquiles]

Since I sold almost all tooling to Milky along with the small lathe, I have been buying new tooling for my larger/heavier 8x14 lathe. I just got a SECO Snap-Tap Internal Threading Holder with with partial profile (48-8 TPI range) threading inserts (3 corners!). I just started using for creating internal threads on cut down 1C's, and it is working GREAT, plus it was on special and more so with the extra 20% off!

http://www.use-enco.com/CGI/INPDFF?PMPAGE=195&PMITEM=RZ619-3811

I will try to post a picture soon

Will

 

[wquiles]

OK, here is some more tool porn ...

Here is my new internal threading tool next to the old one (which I still need to send to Milkey!):

and some more closeups:

 

[gadget_lover]

I guess I'm cheap. Really cheap.

I still use the same internal threading tool as Will used to use. It's a small Harbor Freight (1/4 inch shank) indexible insert holder designed for cutting to a shoulder, using the back end of the tool instead of the tip. It works reasonably well for 16 - 32 tpi. I also have some nicer micro100 threading tools.

But what makes a 5 inch long piece of steel worth $101 as is the toolholder in Will's post. Is it an exotic metal? Is it set to some perfect angle that we can't grind ourselves? Is it just the name?

I still want one, but that's beside the point.

Daniel

 

[Rothrandir]

There is a lot that goes into a toolholder, proper rigidity and support being one of the most important things. Material type, pocket quality, repeatability, angle, all can make a big difference. If you're not in a big hurry, and can take time to mess around getting things to cut well, some of the above may not be that important to you.

For internal threading, I use "TOOL-FLO" BB-312S for smaller sizes, and laydown threading Vardex bars for >.750" or so
The tool-flo holder is nice, because it accepts groove inserts as well as (single-sided) threading inserts. (BNVR-60 GP4 for the 60degree inserts)
I think the bar and a box of inserts was probably around $200? Can't recall, it's been a few months...

For real small stuff, ph Horn has some very nice tools also. (threading well under .250")

Full profile is nice, but for a home shop, a regular 60degree tool works well, and if you need to run some hogs hair or paper over the tips, that's not a big deal.
Having thousands of dollars worth of threading inserts that you rarely, rarely use sucks

 

[PhotonFanatic]

The local Sandvik distributor sells threading inserts by the one, so it's not such a huge outlay of cash to get a range of thread sizes. I've had the same batch of threading inserts since I bought them over a year ago. True, I'm not cranking out high volume, but the point is that with three points per insert, plus their durability, the cost isn't that much.

I'd also suggest getting full form threading inserts, as they make life much easier for the home machinist--you don't have to spend an inordinate amount of time ensuring that your diameter is exact--the full form insert takes care of making perfect threads for you.

As for why pay a lot of money for tool holders? That's like asking why one should buy a Ferrari rather than a Focus. The performance is different. :devil:

Seriously, a carbide bar has much greater rigidity than a steel bar, resulting in better threads, period. And that is especially noticeable when threading in the 4-7X diameter lengths.

 

[wquiles]

I think Daniel is right in that the smaller tool can do the job - so one does not "have" to buy the more expensive tool that I got. But now that I have used both, the "nicer" tool that I got is much stiffer and easier to use (plus my 8x14 lathe is much stiffer, heavier, and solid anyway - that helps as well). Is it worth the $60-70 I paid (on special)? For me it was - I definitely prefer cutting threads with it

Will

 

[precisionworks]

But what makes a 5 inch long piece of steel worth $101

Time invested, nothing but time ...

Not from the standpoint of the manufacturer, as they use a 5-axis machining center + EDM to produce those beautiful holders. You can easily make them in the home shop, given enough time. We made dozens when I worked in the machine shop, as the supervisor enjoyed tinkering & was a top notch toolmaker to boot.

I bill out shop time at $50/hour, and could probably knock one out for $200 including time, materials, heat treat cost, black phosphate cost, etc. $101 makes more sense to me. Or hunt eBay & maybe spend $50.

The lathe is the downpayment, the tooling is the monthly mortgage.

 

[Mirage_Man]

Do you snap your threading inserts often?

Frequently enough that it's got me looking for another system. The inserts that come with the Thinbit Mini threading system are very fragile. If I don't roll out of a thread at the right time chances are it will grab and snap. In aluminum it's not as big a problem but in ti it is. My lathe has some to do with it too but that's another story which will be remedied very soon .

 

[jhanko]

Just for the record, that holder & insert that Will has is on sale now. Also, with the 20% off, it's a great deal. I just ordered the holder, 1 internal insert and 1 external insert for $96 and free shipping.

Jeff

 

[Mirage_Man]

Just for the record, that holder & insert that Will has is on sale now. Also, with the 20% off, it's a great deal. I just ordered the holder, 1 internal insert and 1 external insert for $96 and free shipping.

Jeff

That does look like a decent threading tool. However it has a minimum bore of .750". which is too tight for the work I'm doing. On a M@G it would be fine though. I need something more along the lines of a mini threading tool for my application.

I think I'm gonna pick up a Micro 100 threading tool tomorrow to get me through until I decide which system to go with. I'll do some more looking into the ones recommended here.

 

[PhotonFanatic]

Half inch diameter, including the insert--this gets into 95% of the lights that I'm building. Anything smaller and I use some Sandvik CorocutXS threading bits.

Laydown insert with three points lasts a long, long time.

 

[scott.cr]

I think I'm gonna pick up a Micro 100 threading tool tomorrow to get me through until I decide which system to go with.

I picked up a Micro 100 as a "temporary" tool too! That was three years ago. Have done dozens of internal threading jobs with it and it still looks new. It was like $32 from mscdirect.com.

"There's nothing more permanent than a temporary setup" hahaha...

 

[wquiles]

Half inch diameter, including the insert--this gets into 95% of the lights that I'm building. Anything smaller and I use some Sandvik CorocutXS threading bits.

Laydown insert with three points lasts a long, long time.

I like this one - like a mini-me version of the one I got!

Who makes this one?

Will