PDA

View Full Version : Need help identifying Valenite insert holder



atty
09-16-2010, 11:57 AM
In a frustrated moment last night, I began digging through some archives and came across this insert holder. I was fully confident that Google would yield all the info on this holder I would need, but alas.....NADA. I understand from some posts that perhaps Valenite was bought out by Kennametal, who may have killed off a bunch of Valenite's product lines, etc.

In any event, I'm a lost pup. I'm an insert newbie on top of that. Any way of determining a current insert number/type? Looks like a pretty good holder, so I'd hate to relegate it back to the "I'll get to that later" pile. It's obviously a threading insert: thickness .125 and mounting hole looks to be .0875. I have a bolt threading project coming up, and I thought I might give an insert a try.

http://i591.photobucket.com/albums/ss352/atty5420/100_3760.jpg
http://i591.photobucket.com/albums/ss352/atty5420/100_3761.jpg

wierdscience
09-16-2010, 07:24 PM
You'll need to start by figuring the IC or inscribed circle.That is the largest circle that will fit inside the bounds of the insert shape.Usually its something common like 1/4-3/8-1/2 etc.

The rest of the info needed to spec an insert can be found here-

http://www.carbidedepot.com/formulas-insert-d.htm

motorworks
09-16-2010, 07:48 PM
Sorry
I do not think it's a threading tool.
The insert look like a TNMG-332...
The holder MTENN negative cutter.
Great for chamfers.
e

atty
09-16-2010, 10:48 PM
Well.....my newbie insert label is still intact. From my continuing research, It thought an MTENN was a threading holder.....maybe not.

I did find out from Walter, who apparently consumed Valenite, that it takes a TNMG222, recommended M3 for threading. Does that shed any light?

All that having been said, what does one suggest for threading inserts in low to medium carbon steel? I'm finding this stuff is incredibly proprietary and confusing to say the least. If you get a holder, are you married to that maker's inserts? Big time ignorance being shown here......so easy on me. :confused:

motorworks
09-17-2010, 04:47 PM
Ok
Pleae tell me what you plan to thread
i.e size and pitch
and I will try and help
eddie

lane
09-17-2010, 06:36 PM
That is not a threading insert are holder . Standerd turning and champfering. insert .

JoeLee
09-17-2010, 08:14 PM
You have a very old one.

JL...........

atty
09-17-2010, 10:25 PM
You're right. It's an antique, but apparently functional.

Anyway, the project is 1 1/4" X 7 TPI Grade 5 steel, 5" of thread.

Should I look at insert, carbide brazed tip, or just stick to HSS?

motorworks
09-18-2010, 07:53 AM
Ok
Are you extending an existing threads? Or making bolts...
If you are extending threads..(something I do a lot of for local ship yard) then use the brazed on carbides. I just picked up 10 pcs for 25.00 at Travers in the us.
Bolts are made from the worse material :) So getting a nice thread is not easy.Coolant/oil helps. HHS is great if u have the time to sharpen...I never do..
And if you need info on an insert system let me know.
eddie

atty
09-18-2010, 10:49 AM
Unfortunately, I'll be threading from blanks. You're absolutely correct about the material. I've already experimented with some existing bolts, and they are nasty looking threads. I'm going to talk to the customer about 12L14, but I fear the wear factor is going to eliminate that idea. This is only a quantity of six so, using a better material and then heat treating is also probably out. The threads that I cut on the test bolt were functional, but I would sure hate to have my name on 'em anywhere.

My experience on carbide brazed tips when threading a low grade steel has been a lot of chipping of the carbide. Could be, I just had a lousy grade of bit. As I said, I'm a newbie on inserts, so whatever guidance you have, I'd appreciate.

Boucher
09-18-2010, 11:40 AM
Threading tools come in lots of different flavors but they have many things in common. They are pointed with the angle for the type thread probably in your case a 60. They have side relief built in which your turning insert does not.
1. HSS works great but is a little more difficult to grind into the threading configuration.
2. The brazed carbide threading tools are fairly cheep and workable but they also require sharpening which gets back to grinding.
3. Insert type threading tools avoid the sharpening/grinding problem but cost more and come in numerous different configurations and holding methods. There are vertical, lay down in both partial and full profile, external, internal, Top lock ..etc.
If you want to start with an insert type tool the top lock type or full profile lay down type are probably a little more state of the art. I personally prefer the vertical threading inserts.

I would suggest that you get some cheap material and practice on that. Bolts are not all that expensive but most likely you will make some scrap during the learning process. The nice thing is that you can turn it down and start over on a smaller size.

The 1" material is a good size to start on but even something that large bends a little. Minimuize both your material and tool extensions and run a center if you can. Take some repeat passes with out advancing the cutter and you will probably see some additional material being removed.

Best wishes,

Boucher
09-18-2010, 11:55 AM
Two materials that I like to work with are 416 stainless and 1144 Stressproof. I get the 416 in the 1 1/4" size from the waterwell irrigation people who use it. The stress proof I buy from online metals. I don't know what the material is but that used to make mud pump rods machines very nicely.

PixMan
09-18-2010, 03:52 PM
While the LTE-8 holder is not intended to be a threading tool holder, but in this instance it can be used IF you get an insert with no more than a .0179" radius on the tips.

I've found that holder in my "Turning 2007" Valenite catalog. The insert spec posted is correct, though you could also use a TNMP221, TNMG221 or TNMM221 insert. The TNMG222 has a .031" radius, I think too big for the root of a 1-1/4-7 thread.

The only current insert that makes sense is a Walter Valenite TNMM221 ER-PN1 grade VP5615. It looks like this one but this one is the bigger 5/16" I.C. size.

http://cgi.ebay.com/8pc-TNMM-2-522ER-Grade-V91-Carbide-Inserts-VALENITE-/330238217025?pt=LH_DefaultDomain_0&hash=item4ce3bb4b41

If you get that style, be sure to use the compound infeed as the chip breaker design is not intended for cutting on the "back side".

atty
09-18-2010, 04:19 PM
Thanks, Pix. I was using the insert shown in the pic, and I have no idea what it was, but it appeared to have a radius closer to 1/32" rather than 1/64". Your comment about compound infeed is interesting as this particular insert had no reservation about breaking once I was getting close to the final passes. That tendency had me re-thinking the idea of using inserts for deep threading on Grade 5.

JoeLee
09-18-2010, 04:42 PM
The 12L14 is a dream to machine......... you threads will look almost as if they were ground. Bolts are rolled formed and not cut, most bolts anyway.
Hot and cold rolled don't machine very well, especially when cutting fine threads.

JL...................

PixMan
09-18-2010, 05:00 PM
<snip>
3. Insert type threading tools avoid the sharpening/grinding problem but cost more and come in numerous different configurations and holding methods. There are vertical, lay down in both partial and full profile, external, internal, Top lock …..etc.
If you want to start with an insert type tool the top lock type or full profile lay down type are probably a little more state of the art. I personally prefer the vertical threading inserts.



Me, I'm a lay-down kinda guy. :D

I've amassed nearly the full array of holders (LH, RH, & drop-head for external, 3 different size internal), plus the full compliment of anvils to compensate for high or low lead angles. I'll continue adding different pitch inserts as the opportunities come up, but have the partial profile styles for the oddball threads for now.

In using the full-profile threading inserts, I find I get exceptional thread quality. Rarely is there any chatter to fight, and never is there any burr on the threads. Here's a motorcycle axle I made for a friend using the full-profile inserts, done in 316SS on a manual Victor 1640 lathe.

I prefer the lay-down style to the on-edge (of which I also own Top Notch and tri-corner style holders) because of the cresting but also the anvils used match the lead angle.

http://img.photobucket.com/albums/v466/kenm10759/wheel-adapter/IMG_0398-r.jpg

atty
09-18-2010, 11:40 PM
Nice looking threads. I'd be more than pleased to find my Grade 5 look like that. Unfortunately, they are a little raggy, no matter what I use. Guess I'll have to go to experimenting with different inserts to see what does best. If all else fails, there's always HSS and a lot of sharpening.

Boucher
09-18-2010, 11:57 PM
Cratex the people that make the small rubber abrasive disks also make it in 1/2" square x 6" long sticks with various size grits. It can be used to polish threads. You just slow the spindle down and firmly press it into the threads and let it ride down the threads. It is not going to take off enough to alter the fit but it sure improves the appearance. Try it you will like it. I keep four sticks of different grits on the shelf above the lathe. The vertical threading inserts also come in 5 and 10 positive rake that also cuts a little smoother than the negative rake inserts. Cutting speed has a lot to do with surface finish which means that you should thread at the same speed that produces a good finish turning.

PixMan
09-19-2010, 08:13 AM
Cratex the people that make the small rubber abrasive disks also make it in 1/2" square x 6" long sticks with various size grits. It can be used to polish threads. You just slow the spindle down and firmly press it into the threads and let it ride down the threads. It is not going to take off enough to alter the fit but it sure improves the appearance. Try it you will like it. I keep four sticks of different grits on the shelf above the lathe. The vertical threading inserts also come in 5 and 10 positive rake that also cuts a little smoother than the negative rake inserts. Cutting speed has a lot to do with surface finish which means that you should thread at the same speed that produces a good finish turning.

I get very smooth threads using lay-down inserts and have never had to resort to polishing. In the photo I posted, there's a little bit of fiber from the Scotchbrite wheel I used to deburr the cotter pin hole scattered about the workpiece. I didn't touch the threads themselves with the wheel.

You're correct that cutting speed can improve finish with insert tools, but I find it's impossible to thread at anywhere near the same speed I used for turning. I believe I turned the diameters of that axle at 1800rpm, certainly no less than 1200. No way could I thread at that speed, I'm just not fast enough at engaging/disengaging the half nut. ;) Even when I programmed CNC machines the servos just wouldn't keep up at higher speeds. Depending upon the thread, I might be able to thread at up to 2500rpm. Beyond that the X axis (cross slide) began pulling out before the Z axis (carriage) reached it's position.

Most lay-down threading inserts have an effective 2 to 5 top rake angle, despite the negative canter of the insert seat. I've got some "zero" degree Top Notch style threading inserts, and some "K" inserts with the positive top rake. When I can I still prefer using a full-form for the beautiful rounded crests if nothing else. I do have ground HSS tooling too, and use that for very small threads in tough materials where the carbide might chip. Many of those threads often just get done with a die anyhow. ;)