New threading tool
- Thread starter Brad
- Start date
KeithB
Resident Half Fast Machinist
That's a nice tool Brad. It looks like you got a "universal" 60* insert that can cut threads of any normal size. Very versatile and IMHO world's better than any hand ground HSS cutter. (Unless you can grind a tool perfectly - I sure as snot can't)
Where they really come into their own is with "full profile" inserts designed to cut specific pitches (example - 20 TPI). The thread root (point of the tool) has the proper radius to match the thread pitch and the crest of the thread gets rounded over by the leading and trailing edge of the cutting tooth to the proper radius and also to remove any burring at the thread crest. If you cut the OD to the right diameter, a full profile tool will generate a perfect thread with no filing needed because as you hit the pitch diameter the thread crest gets rounded. Never have to use a thread file.
For one-off jobs the Universal type is great, for mass production the full profile type is worth the investment.
Where they really come into their own is with "full profile" inserts designed to cut specific pitches (example - 20 TPI). The thread root (point of the tool) has the proper radius to match the thread pitch and the crest of the thread gets rounded over by the leading and trailing edge of the cutting tooth to the proper radius and also to remove any burring at the thread crest. If you cut the OD to the right diameter, a full profile tool will generate a perfect thread with no filing needed because as you hit the pitch diameter the thread crest gets rounded. Never have to use a thread file.
For one-off jobs the Universal type is great, for mass production the full profile type is worth the investment.
I will likely invest in a few full profile insert sets for things like 14 TPI that I cut frequently. Being able to have "perfect" threads each time has a certain appeal.
The chip told me this tool was going to cut far nicer threads than I was getting with my ground tool. Might be because I also can't grind a perfect 60° angle?
The set also includes a tool for internal threads. Won't work for anything under 1/2" or so but for larger diameter holes it beats grinding my own.
The chip told me this tool was going to cut far nicer threads than I was getting with my ground tool. Might be because I also can't grind a perfect 60° angle?
The set also includes a tool for internal threads. Won't work for anything under 1/2" or so but for larger diameter holes it beats grinding my own.
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Ian
Notorious member
That's cool, Brad, those will save you a lot of time and fiddling. One day I'll get into insert tooling, the carbide stuff seems to be indispensable for cutting really hard metal really fast. Not going to peel a purple chip off of 4130 for feet at a time at .200" DOC with my machine though.
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KeithB
Resident Half Fast Machinist
I like the repeatability and wear resistance of carbide. Once I get things dialed in, if I chip or dull an insert tool I can put in a new, sharp tool w/o removing the toolholder to sharpen the tool, and I can be pretty sure the tool will make a cut close to the right size if I go back to the same position. For most of the turning and facing you will likely do getting a positive rake toolholder that will use a TPU or TPG 32# carbide might be worth considering. The inserts are cheap and available in a lot of different grades/coatings/quality. I have milling cutters and lathe tools that use the same inserts so one size fits several tools for different uses. The last digit represents the tip diameter, so a TPU321 has a 1/64" (.015") tip radius, a TPU322 has a 2/64" (.031") tip radius.
Most small machines don't have the torque/power to use negative rake carbide tools effectively, but positive rake carbide tooling is a different story. Brad's new laydown threading tool uses a positive rake insert and we can all see in the video how smooth it cuts and how the chip curls off.
I believe I have seen ACME and square thread inserts available to fit the same tool holder type.
Most small machines don't have the torque/power to use negative rake carbide tools effectively, but positive rake carbide tooling is a different story. Brad's new laydown threading tool uses a positive rake insert and we can all see in the video how smooth it cuts and how the chip curls off.
I believe I have seen ACME and square thread inserts available to fit the same tool holder type.
RicinYakima
High Steppes of Eastern Washington
OK, all you smart guys, will any of that stuff fit in my 1940's Atlas 6", with lantern tool holder, lathe?
smokeywolf
Well-Known Member
Insert tools can be mighty darned convenient. For folks who earn their living in the machine shop, like Keith pointed out, the repeatability and ability to swap out a dull insert for a sharp one in the middle of a job can really save time and frustration.
Although I've used them a time or two, I don't own any insert tooling for the mill. I do use CNMG-431 and 432 on 3/4" holders for turning and facing on the lathe. With the rhombus shape inserts I get 8 corners.
I actually didn't start using insert tooling until I'd been machining for nearly 15 years.
For me, where insert tooling really shines is a good triangle or trigon insert at the business end of a solid carbide boring bar.
Don't know about now, hands being too shaky, but when I was earning my living at it, I was better than average at grinding toolbits.
As far as having to do a production run of a male thread, I use a geometric die head. Spending nearly my entire machining career doing R & D/prototype work I never ran into having to do a production run of female threads.
Although I've used them a time or two, I don't own any insert tooling for the mill. I do use CNMG-431 and 432 on 3/4" holders for turning and facing on the lathe. With the rhombus shape inserts I get 8 corners.
I actually didn't start using insert tooling until I'd been machining for nearly 15 years.
For me, where insert tooling really shines is a good triangle or trigon insert at the business end of a solid carbide boring bar.
Don't know about now, hands being too shaky, but when I was earning my living at it, I was better than average at grinding toolbits.
As far as having to do a production run of a male thread, I use a geometric die head. Spending nearly my entire machining career doing R & D/prototype work I never ran into having to do a production run of female threads.
I need to get on the lathe wagon again. I had backed off a fair bit the past few months. I got to chasing equipment around at auctions. Think I am pretty well set for now except a few indicators.
My next major purchase is going to be more tool holders.
I did get a machinist box full of goodies a while back. Built a roll around stand for it last Friday. Not a Kennedy but serves the purpose and is in good shape.
I got side tracked this spring after a prairie dog hunt. 20 caliber and under bug has bitten me pretty hard. 17 Hornet, 17 Remington and a 204 Ruger all on the CZ 527 platform. Put together a savage 204, tripped over a savage in 223 for cheap. Figured to tear it down and use it for a build. I was told be the seller it was a very good shooter, so I shot it. It will stay as it is till it shows me different.
Then of coarse a few needed upgraded on glass..........$$$
Don't throw rocks at me, lol all of the above digest full length gas check type projectiles.
To redeem myself I did cast up about 2k of 357,41,44 and 45's a while back.
That tool will be on my want list over my lathe.
Jeff
My next major purchase is going to be more tool holders.
I did get a machinist box full of goodies a while back. Built a roll around stand for it last Friday. Not a Kennedy but serves the purpose and is in good shape.
I got side tracked this spring after a prairie dog hunt. 20 caliber and under bug has bitten me pretty hard. 17 Hornet, 17 Remington and a 204 Ruger all on the CZ 527 platform. Put together a savage 204, tripped over a savage in 223 for cheap. Figured to tear it down and use it for a build. I was told be the seller it was a very good shooter, so I shot it. It will stay as it is till it shows me different.
Then of coarse a few needed upgraded on glass..........$$$
Don't throw rocks at me, lol all of the above digest full length gas check type projectiles.
To redeem myself I did cast up about 2k of 357,41,44 and 45's a while back.
That tool will be on my want list over my lathe.
Jeff
RicinYakima
High Steppes of Eastern Washington
Here is a picture. They are designed to control tool to work angle with the rocker, and I don't know how to make an adjustable by 0.001" flat presentation piece.
Should be. Get a barrel, turn and thread the shank. Crown and cut chamber.
F
freebullet
Guest
That is awesome, Brad.
Pistolero
Well-Known Member
Yes, I got one of those with my set of insert tools earlier in the year. They are really nice. I have some good HSS
thread cutting bits ground on a friend's tool grinder with accurate angle setting gauges, but the insert
still cuts a bit better.
I am getting to really like inserts.
The video is a bit disconcerting, being mounted on the tool mount so tracking with
the tool. A weird perspective, I am used to viewing standing still like the bed.
Nice video, though.
This is the set I got. I think it should work on the 6" Atlas, although maybe a bit large. What
is the max width of the lantern hole? Will it take 1/2" width?
http://www.shars.com/products/index...ders/1-2-indexable-carbide-turning-tool-set-1
bcan use with the lantern tool holder, but also a good time to consider an upgrade
to a quick change tool post.
Bill
thread cutting bits ground on a friend's tool grinder with accurate angle setting gauges, but the insert
still cuts a bit better.
I am getting to really like inserts.
The video is a bit disconcerting, being mounted on the tool mount so tracking with
the tool. A weird perspective, I am used to viewing standing still like the bed.
Nice video, though.
This is the set I got. I think it should work on the 6" Atlas, although maybe a bit large. What
is the max width of the lantern hole? Will it take 1/2" width?
http://www.shars.com/products/index...ders/1-2-indexable-carbide-turning-tool-set-1
bcan use with the lantern tool holder, but also a good time to consider an upgrade
to a quick change tool post.
Bill
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RicinYakima
High Steppes of Eastern Washington
No, I think 5/16" is the maximum. I see that they make them, just out of stock. Put in a notify address. Thanks.
Jeff Michel
Member
ER11 (external thread) IR11 (internal thread) a 16 or 22 will probably be way too big. I use an 11 on my 7" Myford. They are in abundance all over ebay.
Pistolero
Well-Known Member
For the smaller lathe, this uses a different kind of threading insert, but is 1/4" shank, so should fit the existing
lantern toolpost.
http://www.shars.com/1-4-indexable-carbide-turning-tool-set-1
Of course, if you can afford it, a AXA size Aloris QC tool post Chinese clone can be picked up
for around $100 or so with a few QC tool holders. They will probably hold at least 3/8" tool holders. There are
3/8" sets.
http://www.shars.com/3-8-indexable-carbide-turning-tool-set-1
I upgraded my previous Sheldon lathe to a QC Aloris clone tool post and tried some very inexpensive small
indexable cutters. The set I got from Shars have proven to be much better quality than the first ones I tried.
Mostly it comes down to how much can you justify and budget to put into upgrading. That is a question which
has different answers for each of us. HS tools and lantern tool posts are old tech, but still will do the
job reasonably well, so upgrading is a choice for each of us to consider. When money was tight, I stuck to
HS cutters and the original lantern tool post. Years later, as more money was available, I was able to afford
to upgrade.
Brad - I understood (after a few seconds of disorientation) what the camera was
doing. It is just the opposite of what I normally see.....pretty weird at first, like
you say, it seems like the chuck moves!
Just shows what changing our
reference coordinate system does to our percerptions.
It does show the cutter nicely, though.
Bill
lantern toolpost.
http://www.shars.com/1-4-indexable-carbide-turning-tool-set-1
Of course, if you can afford it, a AXA size Aloris QC tool post Chinese clone can be picked up
for around $100 or so with a few QC tool holders. They will probably hold at least 3/8" tool holders. There are
3/8" sets.
http://www.shars.com/3-8-indexable-carbide-turning-tool-set-1
I upgraded my previous Sheldon lathe to a QC Aloris clone tool post and tried some very inexpensive small
indexable cutters. The set I got from Shars have proven to be much better quality than the first ones I tried.
Mostly it comes down to how much can you justify and budget to put into upgrading. That is a question which
has different answers for each of us. HS tools and lantern tool posts are old tech, but still will do the
job reasonably well, so upgrading is a choice for each of us to consider. When money was tight, I stuck to
HS cutters and the original lantern tool post. Years later, as more money was available, I was able to afford
to upgrade.
Brad - I understood (after a few seconds of disorientation) what the camera was
doing. It is just the opposite of what I normally see.....pretty weird at first, like
you say, it seems like the chuck moves!
Just shows what changing ourreference coordinate system does to our percerptions.
It does show the cutter nicely, though.
Bill
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Ian
Notorious member
I got .308 basic go, no-go gauges and both wrenches if you need to borrow. Please start from a blank where YOU can control the thread fit, the aftermarket Savage barrels all flop around in the receiver threads so badly that they're difficult to get centered in the receiver. I also recommend the extra-thick recoil lug from Brownells, and do turn an indicating mandrel for the ID of the receiver and face the front of the receiver, because it won't be square and it won't be flat.