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mototed
05-03-2009, 01:41 PM
I ordered one of these http://www.use-enco.com/CGI/INSRIT?PMAKA=327-0394 I need a 1" x 14 tpi internal all the way to a shoulder. Thought I'd give one a try. I have been using HSS hand ground tools. My question is do these work in the same maner as far as compound set at 29.5 to the left? Can you still use slow speeds?
Tanks in advance for your time
Ted

J. R. Williams
05-03-2009, 01:47 PM
I have been using the small version of the tool for many years and it works in the same manner as any threading tool. Be careful and not hit the end of the tool against the bottom of the hole.
JRW

juergenwt
05-03-2009, 02:11 PM
Why would you go to carbide?

mototed
05-03-2009, 02:31 PM
I confess, I just wanted a new tool/toy to play with:)
This also looked like a quick solution to bottom threads in 4140 steel.
I do OK at grinding bits, but for some reason I can't wrap my head around on how to make a tool that will thread all the way to the bottom stop
Ted

SDL
05-03-2009, 02:47 PM
Why would you go to carbide?

To get a full form tool with crest as well as tip radi?

Steve Larner

Glenn Wegman
05-03-2009, 04:34 PM
Why not use a left hand tool and thread away from the shoulder?

Thread in reverse with the tool on the far side facing away from you if you have concerns about hitting the shoulder. Just requires a small relief groove at the shoulder.

Unless you have a threaded spindle nose of course!

Glenn

DR
05-03-2009, 05:10 PM
With a full profile insert you can get the correct pitch diameter by only measuring the OD (male thread) or ID (female thread).

Those are not the recommended way for precision thread measuring, but they work.

juergenwt
05-04-2009, 03:04 PM
Mototed - best way to cut an internal thread is to have an undercut in the back. So grind the leading angle of your bit to be just the right length for the thread you are cutting. The undercut has to be wider than 1/2 of your 60 deg. tool. How much is up to you and how much experience you have. Because unless you have a lathe with an automatic thread release you will have to manually kick out your split nut when you reach the undercut. Since you can not see what you are cutting - mount a drop indicator on your bed and set it to about .030 past the zero point (depends on the thread) when you touch the back with your tool before starting to cut. (your indicator against the compound).
Now you will have to compensate for moving your compound at 29 1/2 deg back as you progress. Trig it out and allow the compound to move past the same amount past the zero mark on your indicator. Not as complicated as it sounds. Make sure your undercut dia is below the double depth of your thread. Caution: do not set a solid stop!! You WILL break your split nut!

Ron of Va
05-04-2009, 05:55 PM
I ordered one of these http://www.use-enco.com/CGI/INSRIT?PMAKA=327-0394 I need a 1" x 14 tpi internal all the way to a shoulder. Thought I'd give one a try. I have been using HSS hand ground tools. My question is do these work in the same maner as far as compound set at 29.5 to the left? Can you still use slow speeds?
Tanks in advance for your time
Ted

I hate to be the one to tell you this, but you won’t be able to cut a 14 thread pitch with that tool.

That is an “11” tool = ¼ inch. The thread pitches it will cut are 16-48.

Carmex inserts are listed on page 775 of the MSC catalog. See for yourself.
http://www1.mscdirect.com/CGI/NNPDFF?PMPAGE=775&PARTPG=GSDRVSM&PMT4NO=62666416&PMITEM=08716136&PMCTLG=00&PMT4TP=*LTIP

I hope I am wrong.

mototed
05-05-2009, 05:55 PM
Thanks Ron,
You're right, I'm new to threading inserts, but was aware that they had limited thread range. Just looked at Enco's catalog and they did not mention that important fact. Now I'm really confused. will this holder work with 16 IR AG 60i insert witch has a 3/8" IC ?
Ted

Ron of Va
05-05-2009, 06:20 PM
Sixteen (3/8”) will not fit into an eleven (1/4”) tool holder. I believe that Carmex tool holders “might” be proprietary, in that they only accept Carmex inserts. You might want to call and check on that.

A couple of things to consider: The “11” tool fits a minimum bore of .58, whereas the “16” fits a minimum bore of .90. Most of the stuff I do is smaller holes than .90”.

I don’t know what kind of tool post you have, the “11” fits a BXA tool holder because the shaft is 5/8”, whereas the “16” needs a quick release holder opening of “¾” and isn’t easily adapted to the BXA quick release tool holders.

(Although Grizzly makes a 3/4” opening in one of their tool holders, but it isn’t in the catalog, it is the one that comes from the factory with the machine. If you need it, I think I can find the part number)

I will say this about Carmex products, they are excellent. I have the Carmex Ultra-Miniature solid carbide tool holder, which will reach into a ¼” hole an inch deep. It is a sweet tool. But it is very pricy, and I have to wait for the sales to buy inserts.

lazlo
05-05-2009, 06:57 PM
Sixteen (3/8”) will not fit into an eleven (1/4”) tool holder. I believe that Carmex tool holders “might” be proprietary, in that they only accept Carmex inserts. You might want to call and check on that.

Those are standard lay-down threading inserts. I use the same inserts on a Dorian BXA threading tool.

But you're absolutely right about the sizes of the inserts and the thread ranges.

Ron of Va
05-05-2009, 07:36 PM
Lazlo: Thanks for pointing out the inserts weren’t proprietary.

Mototed:
Not to discourage you about the Carmex, but this will do what you want for a lot less money. http://www.grizzly.com/products/h8305 It takes “16” inserts into a minimum bore of .748”. No more grinding tools. You can still buy another brand of full profile inserts.

Don’t forget Carmex also makes an “08” (3/16) or “Miniature” tool holder that will reach into a .354 hole .830” deep. I can’t seem to find the full profile inserts for the “08”, they should make them, since they make them for the “06” (5/32) ultra miniature. I would rather have the "08" because of the smaller holes that can be threaded, and you can find 08 Carmex inserts on ebay.

BadDog
05-05-2009, 08:02 PM
Not too long ago, I wound up with a Kennametal "Top Notch" holder. Inserts are pricey, but not too bad from surplus/ebay. And they have any sort of profile you might want. Tiny/fine threads, to big honkin' threads. O-ring grooves, snap ring grooves, ACME thread, whitworth, all sorts of stuff. I like it very much...

JRouche
05-06-2009, 11:31 PM
Not too long ago, I wound up with a Kennametal "Top Notch" holder. Inserts are pricey, but not too bad from surplus/ebay. And they have any sort of profile you might want. Tiny/fine threads, to big honkin' threads. O-ring grooves, snap ring grooves, ACME thread, whitworth, all sorts of stuff. I like it very much...


I like the top notch stuff. I bought a bar and some bits off ebay years ago and really liked the cut. But,,, the inserts were still expensive. Well, found a guy selling the TN inserts cept they were flat, no grind on them, maybe a grooving bit. But they were really inexpensive. So I bought them all. I have enough kennametal inserts and some holders (Inside and outside) to last the duration.

Got some decent grinders so Ill contour the tip as I need it. I like the carbide they use for the inserts. Seems to hold a razors edge for a long time. Even with slow speeds. And its tough, doesnt chip off like some of the stuff Ive used, even with a stall (my fault). Edge stays intact, havent chipped an edge yet. I have many times with other inserts. JR

tattoomike68
05-07-2009, 12:39 AM
I ordered one of these http://www.use-enco.com/CGI/INSRIT?PMAKA=327-0394 I need a 1" x 14 tpi internal all the way to a shoulder. Thought I'd give one a try. I have been using HSS hand ground tools. My question is do these work in the same maner as far as compound set at 29.5 to the left? Can you still use slow speeds?
Tanks in advance for your time
Ted

just tap the hole and cut off the threads on the male part for a few threads. What kind of dumb azz engineer wants threads right up to an internal shoulder? He needs kicked right in his microscopic nut sack.

man there are times where stuff is made all wrong and this is one of those times.

tattoomike68
05-07-2009, 12:42 AM
Not too long ago, I wound up with a Kennametal "Top Notch" holder. Inserts are pricey, but not too bad from surplus/ebay. And they have any sort of profile you might want. Tiny/fine threads, to big honkin' threads. O-ring grooves, snap ring grooves, ACME thread, whitworth, all sorts of stuff. I like it very much...


Those are the ticket, Kennametal makes great tools IMHO.

Deja Vu
05-07-2009, 11:20 AM
just tap the hole and cut off the threads on the male part for a few threads. What kind of dumb azz engineer wants threads right up to an internal shoulder? He needs kicked right in his microscopic nut sack.

man there are times where stuff is made all wrong and this is one of those times.

Yah...I was wondering just what application would require threads right up to a shoulder.... anyone have some examples that would not work without full threads to the shoulder?

TGTool
05-07-2009, 11:43 AM
just tap the hole and cut off the threads on the male part for a few threads. What kind of dumb azz engineer wants threads right up to an internal shoulder? He needs kicked right in his microscopic nut sack.

man there are times where stuff is made all wrong and this is one of those times.

Well, I do some things like collet adapters for lathes. The collet small end is noticeably smaller than the lathe spindles which makes for an internal thread up to a shoulder. I suppose I could tell my customers to turn off the threads from the first 3/8" of their spindle so I don't have as much problem with a shoulder. :rolleyes:

lazlo
05-07-2009, 02:42 PM
Not too long ago, I wound up with a Kennametal "Top Notch" holder. Inserts are pricey, but not too bad from surplus/ebay. And they have any sort of profile you might want.

I have TopNotch tooling too :) For those who aren't familiar, the TopNotch insert is on its edge, as opposed to the laydown inserts, which are like flat TPG-style inserts with thread forms ground on the three tips.

The pro's on PM seem to be evenly divided between the TopNotch on-edge style and the laydown style, but I can't really decide which I like better. I did find a pack of Kennametal Poly-V groove TopNotch inserts, which makes cutting Poly-V sheaves a breeze!

The TopNotch inserts also come in all kinds of groove forms.

digger_doug
05-07-2009, 03:19 PM
just tap the hole and cut off the threads on the male part for a few threads. What kind of dumb azz engineer wants threads right up to an internal shoulder? He needs kicked right in his microscopic nut sack.

man there are times where stuff is made all wrong and this is one of those times.


Mike,
do you obey the speed limit when driving ? do you stop at the
redlight in town ?

I'm that guy that put's the stuff on the drawing...I used to be
one of the guys cranking the handwheels in the shop.

Now it's o.k. to ask if the engineer (or designer) if they REALLY needs
those threads that way, we all make mistakes,(run it up the flagpole)
but just blowing off the print aint' gonna cut it.

If I put it on the print, I need it. There may be many reasons why.
I feel for the guy that has to make it, and I ussually will ask
if they can do it before I draw it, but if I need it, I need it.

I have a friend (has a 4 year engineering degree) that didn't have
4140-ht in stock (he runs a screw machine shop), so he substituted
12L14 leaded stock instead, never telling the customer because.
"I know what this part does, and they don't need it"

It's a spool piece, on a safety valve, on 8,000 gallon gasoline
tank trucks........that drive down the same road we share.

tnx
Doug