Speed/Feed ???
- Thread starter Hal
- Start date
D
Dennis Sorensen
Guest
ultramagmed
JKM
Pictures????
Dennis,
Do you have any photos of the tooling profiles you use? I have a grinder and have been experimenting with differnet tool profiles, and was wondering if you could offer any pictures of what works for you.
Thanks, MED
Dennis,
Do you have any photos of the tooling profiles you use? I have a grinder and have been experimenting with differnet tool profiles, and was wondering if you could offer any pictures of what works for you.
Thanks, MED
D
Dennis Sorensen
Guest
I just grind a new bit to 60 degrees, removing most from the right side and just a little on the left side so I can get close to the shoulder when threading right to left. It is flat on top and hollow ground on the relief. I set it just below center on the work. I feed in at 30 degrees. It works well for me. I don't take big cuts and often will chase the thread at the previous setting before advancing the compound for the next cut.
Feed and Speed
I try to follow the tooling recomendations.
Turning with Carbide I run at 600+ RPMs
Threading with HSS I run at 70- 175 RPMs.
Chambering larger than 30 caliber I run flush presures 35-125 psi and 125-375 RPMs.
Running smaller than 6mm I run 75-125 psi and 45-70 RPMs.
With light feeds and high presure flushing is less frequent.
With heavy feeds I check and flush more frequently especially in the shoulder areas of the reamer. Larger swarf does not flow out of the reamer flutes as easily as the smaller light stuff does.
Chambering with carbide reamers is a whole different game. It is balls to the wall 600 RPMS at 125 psi. The reamer must be held rigid by the tool holder.
Rustystud
I try to follow the tooling recomendations.
Turning with Carbide I run at 600+ RPMs
Threading with HSS I run at 70- 175 RPMs.
Chambering larger than 30 caliber I run flush presures 35-125 psi and 125-375 RPMs.
Running smaller than 6mm I run 75-125 psi and 45-70 RPMs.
With light feeds and high presure flushing is less frequent.
With heavy feeds I check and flush more frequently especially in the shoulder areas of the reamer. Larger swarf does not flow out of the reamer flutes as easily as the smaller light stuff does.
Chambering with carbide reamers is a whole different game. It is balls to the wall 600 RPMS at 125 psi. The reamer must be held rigid by the tool holder.
Rustystud
Dave Tooley
Active member
All carbide except the reamer
rough turn at 800 RPM's
finish turn at 1250 RPM's
Thread at 200RPMs
rough chamber at 125RPM's
finsh chamber as slow as it will run
Shell Garia 623 cutting oil for reaming.
Moly Dee for threading
Dave
rough turn at 800 RPM's
finish turn at 1250 RPM's
Thread at 200RPMs
rough chamber at 125RPM's
finsh chamber as slow as it will run
Shell Garia 623 cutting oil for reaming.
Moly Dee for threading
Dave
JerrySharrett
Senile Member
Turn at 500 rpm-dry-HSS Co lipped--0.003" IPR
About 0.050" DOC roughing, about 0.010" DOC finishing
Thread at 130 -Tin coated 5 degree positive carbide-Hi sulfur oil
(TPMC-32NV C5-Tin)
Ream at 85 rpm-Hi sulfur oil.
About 0.050" DOC roughing, about 0.010" DOC finishing
Thread at 130 -Tin coated 5 degree positive carbide-Hi sulfur oil
(TPMC-32NV C5-Tin)
Ream at 85 rpm-Hi sulfur oil.
Tenon 800-1200 RPM w/ISCAR WPEX IC908 insert & sometimes finish w/Kennemetal DCGT HP KC5010
Roughing feed? Just hog it off probably .030-.050" at whatever feed feels good turning the apron wheel. Finish ~.005"-.010" @ .004-.005 IPR
Thread ~100-175 RPM (I typically don't cut thread reliefs so it depends on how fast my hands are reacting to my brain that day) w/ISCAR full profile IC908 inserts & compound @ 29°
Ream ~50-75 RPM HSS
Currently using Chevron Elite Cut AXH (discontinued) and have used Texaco Transultex H (available again) and Mobil Omega. All about the same. For threading and reaming Chev AXH w/some Castrol Moly Dee added.
As an added note the Kennemetal DCGT (turning) and DPGT (boring) with the HP profile and KC5010 grade makes for a really fine finish on SS barrel steel. The HP profile is a little fragile though. I used to use hand ground and honed HSS for crowning but now use the DPGT set just above center which leaves a very sharp burr free crown. Bill Myers and his friend Tony turned me on to this insert.
Roughing feed? Just hog it off probably .030-.050" at whatever feed feels good turning the apron wheel. Finish ~.005"-.010" @ .004-.005 IPR
Thread ~100-175 RPM (I typically don't cut thread reliefs so it depends on how fast my hands are reacting to my brain that day) w/ISCAR full profile IC908 inserts & compound @ 29°
Ream ~50-75 RPM HSS
Currently using Chevron Elite Cut AXH (discontinued) and have used Texaco Transultex H (available again) and Mobil Omega. All about the same. For threading and reaming Chev AXH w/some Castrol Moly Dee added.
As an added note the Kennemetal DCGT (turning) and DPGT (boring) with the HP profile and KC5010 grade makes for a really fine finish on SS barrel steel. The HP profile is a little fragile though. I used to use hand ground and honed HSS for crowning but now use the DPGT set just above center which leaves a very sharp burr free crown. Bill Myers and his friend Tony turned me on to this insert.
Last edited:
Whats the cause of a groove in the finished surface?
I'll be turning a finishing pass (.005), the surface looking good, smooth and shiny, and than the cutter will leave a groove around the circumference of the shaft.
I'm using a diamond shaped profile carbide insert, no coolant and working with 416 SS.
The insert doesn't have a chip breaking groove and swarf, birds nest around cutter.
This will happen with a carbide inset or a HSS insert or ground bit.
I think some swarf gets under the tool bit.
Hal
I'll be turning a finishing pass (.005), the surface looking good, smooth and shiny, and than the cutter will leave a groove around the circumference of the shaft.
I'm using a diamond shaped profile carbide insert, no coolant and working with 416 SS.
The insert doesn't have a chip breaking groove and swarf, birds nest around cutter.
This will happen with a carbide inset or a HSS insert or ground bit.
I think some swarf gets under the tool bit.
Hal
ultramagmed
JKM
I've also had that same problem, don't know what causes it, hopefully someone that knows will post.
MED
MED
L
LesWard
Guest
I am just a hobby machinist so take this for what its worth.
I would look for a piece of swarf stuck in between the work and the tool, the cause could be , not enough relief, or tool set to high, or both.
I like to set up just slightly below center.
Aloha, Les
I would look for a piece of swarf stuck in between the work and the tool, the cause could be , not enough relief, or tool set to high, or both.
I like to set up just slightly below center.
Aloha, Les
W
wnroscoe
Guest
416R SS and 4140 CM
Tennon Turning and Facing with Indexable Insert Tools and Carbide 800 rpm
Feed of .007" for Rough and .002" for final pass
Threading 200 rpm with Indexable Insert Tools and Rigid Tap Cutting Oil
Chambering 70 rpm with Rigid Tap Cutting Oil
Marks on the work piece could be the tool tip being too high, rubbing on your work. Try setting the tool tip even with the tip of your dead center or slightly below.
Tennon Turning and Facing with Indexable Insert Tools and Carbide 800 rpm
Feed of .007" for Rough and .002" for final pass
Threading 200 rpm with Indexable Insert Tools and Rigid Tap Cutting Oil
Chambering 70 rpm with Rigid Tap Cutting Oil
Marks on the work piece could be the tool tip being too high, rubbing on your work. Try setting the tool tip even with the tip of your dead center or slightly below.
JerrySharrett
Senile Member
If you are talking about an occasional torn looking groove while the rest of the surface is shiny, you are witnessing the effects of BUE (Built Up Edge).
Things that reduce BUE are, faster SFM (surface feet per minute), faster feedrate (increases the scallop height), more positive top and side rake of the cutting edge, better machinability (as in "free cutting", adding lead to the alloy for example) and better lubricity (a cutting fluid to coat the surface of the tool and workpiece).
There are actually some conditions in high-speed machining where BUE is your friend (like the wind is your friend-HA). In properly controlled BUE conditions, the BUE actually takes the abrasive wear away from the cutting tool.
Here is a decent explanation;
http://en.wikipedia.org/wiki/Built_up_edge
http://en.wikipedia.org/wiki/Machinability
jackie schmidt
New member
Speeds
I do most turning at 750-1000 RPM, with anywhere from .005 to .010 feed for roughing, .0015 for finishing.
,
I thread at 350 rpm, I do go to the shoulder with no thread relief. But, keep in mind, I have been doing this for 45 years.
We have switched over to the high sulphurized Ridgid Black Cutting Oil. We buy it in 55 gallon drums. It is as good as any I have used in the way of heavy sulphurized cutting oils.
I use regular TIN inserts, I can look at the number tommorrow. I am not a fan of full profile laydown inserts. Reason?? We machine too many custom, (as in non standard), threads.
I also thread straight in. That should scare everyone.
As for chambering speed, I ream by hand, after removing 98 percent of the stock by single point boring.........jackie
I do most turning at 750-1000 RPM, with anywhere from .005 to .010 feed for roughing, .0015 for finishing.
,
I thread at 350 rpm, I do go to the shoulder with no thread relief. But, keep in mind, I have been doing this for 45 years.
We have switched over to the high sulphurized Ridgid Black Cutting Oil. We buy it in 55 gallon drums. It is as good as any I have used in the way of heavy sulphurized cutting oils.
I use regular TIN inserts, I can look at the number tommorrow. I am not a fan of full profile laydown inserts. Reason?? We machine too many custom, (as in non standard), threads.
I also thread straight in. That should scare everyone.
As for chambering speed, I ream by hand, after removing 98 percent of the stock by single point boring.........jackie
Jackie
I'll have to try that light .0015 for a finish cut. I thought you had to take a deeper cut when using carbide.
WSnider.
What shape are the WPEX and the DCGT inerts?
Well back to the shop for more practice on the surface finish, still not good enough to take to the fair
.
I go and try a few suggestions.
Thanks
Hal
I'll have to try that light .0015 for a finish cut. I thought you had to take a deeper cut when using carbide.
WSnider.
What shape are the WPEX and the DCGT inerts?
Well back to the shop for more practice on the surface finish, still not good enough to take to the fair
. I go and try a few suggestions.
Thanks
Hal
JerrySharrett
Senile Member
The finish cut needs to be small, IF you want an exact diameter size (heavy cut-material pushes off), BUT you must have a sharp edge insert. No edge radius and no K-land.Jackie
I'll have to try that light .0015 for a finish cut. I thought you had to take a deeper cut when using carbide.
WSnider.
What shape are the WPEX and the DCGT inerts?
Well back to the shop for more practice on the surface finish, still not good enough to take to the fair
I go and try a few suggestions.
Thanks
Hal
H
henrya
Guest
Hal,
CPMT inserts work really well for me in a Kennametal SCLP boring bar. They are 80 degree diamond if that will work with your tool holder you might try some.
Henry
CPMT inserts work really well for me in a Kennametal SCLP boring bar. They are 80 degree diamond if that will work with your tool holder you might try some.
Henry
jackie schmidt
New member
???????????
I did not mean leaving .0015 for the finish cut, I meant that I use the .0015 feed rate, which is the finest my Pratt & Whitney cuts.
For finish cuts, who knows??. I am a stickler to making diameters dead on from barrel to barrel, if there is .003 left for the finish,I take that, if it is less, I take that. Let's just say I like to leave less than .005 for a finish cut.
Most craftsmen do not run inserts with enough RPM, (which translates to surface ft on diameter), to allow the carbide inserts to performas they should. Of course, most of these tools are designed to work in machines that are rather heavilly constructed and in tight working order. The fact is, many Hobbyist own machines that are from an era that did not have this in mind.
I probably should not even post on threads such as this. I do my work on a 14 inch Pratt & Whitney tool room lathe that my shop owns. Heck, if I tried to use the same practices on many of the machines that Hobbyist and Gunsmiths used, I would end up with a big mess........jackie
I did not mean leaving .0015 for the finish cut, I meant that I use the .0015 feed rate, which is the finest my Pratt & Whitney cuts.
For finish cuts, who knows??. I am a stickler to making diameters dead on from barrel to barrel, if there is .003 left for the finish,I take that, if it is less, I take that. Let's just say I like to leave less than .005 for a finish cut.
Most craftsmen do not run inserts with enough RPM, (which translates to surface ft on diameter), to allow the carbide inserts to performas they should. Of course, most of these tools are designed to work in machines that are rather heavilly constructed and in tight working order. The fact is, many Hobbyist own machines that are from an era that did not have this in mind.
I probably should not even post on threads such as this. I do my work on a 14 inch Pratt & Whitney tool room lathe that my shop owns. Heck, if I tried to use the same practices on many of the machines that Hobbyist and Gunsmiths used, I would end up with a big mess........jackie