it was purchased on amazon. :chinese::001_9898::001_9898:
https://www.amazon.com/gp/product/B01N0RIR0W/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B01N0RIR0W/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
![20170401_132548[1].jpg](/forum/data/attachments/24/24902-67bda85c9e50c26b7c727eb2ed4531fb.jpg)
![20170401_132559[1].jpg](/forum/data/attachments/24/24903-6eb9adc535a370277cf4e7d3cbd70bf6.jpg)
the tooling and finishing on these drill bits is light years past that chinese junk i first
had. heading out to the tool shed in a bit to see how they work.
on another note; i need to make some of these knobs with a top side bore that has
a flat bottom. some people like their knobs made a certain way. so would i be better
off to drill the hole to depth then use a boring bar or an end mill? all these cuts will
be interrupted. materials can be aluminum or run of the mill CRS.
had. heading out to the tool shed in a bit to see how they work.
on another note; i need to make some of these knobs with a top side bore that has
a flat bottom. some people like their knobs made a certain way. so would i be better
off to drill the hole to depth then use a boring bar or an end mill? all these cuts will
be interrupted. materials can be aluminum or run of the mill CRS.
ok. i'll pm you with some more details in the morning. i just finished up drilling the rest of the
knobs with the new drill bits. much smoother. but the rpm that i used initially caused some chattering.
the bit diam is .625", material is T6063 aluminum. its says to run it at 1200 rpm, but cuts are much
cleaner at 250 rpm.
rookie mistakes i am sure.....
:thumbsup:
phil
knobs with the new drill bits. much smoother. but the rpm that i used initially caused some chattering.
the bit diam is .625", material is T6063 aluminum. its says to run it at 1200 rpm, but cuts are much
cleaner at 250 rpm.
rookie mistakes i am sure.....
:thumbsup:
phil
Phil,
If I remember right, you are running a vintage South Bend. This lends itself to trial and error a bit. With a lantern tool post, you could make a boring bar from a chipped-tooth old tap by grinding the tap very slow and keeping the water handy for cooling. I'm guessing you are using 6061 T4 or T6 aluminum round bar or C1018 Cold Rolled Steel. Both have fairly low machinability numbers and are pretty friendly. For each material, hone any High Speed Steel boring bar (tap re-ground) or lantern tool post tool bit with a medium and fine grit diamond hone till they are really sharp, fingernail test. That, along with some Cool Tool II for lubrication and cooling should improve your results. With Carbide, your slower lathe should produce an acceptable finish. This has been my experience with my 1939 Sheldon overhead leather belt drive 10 X26 lathe running at a whopping 508 rpms. Drill to depth with a smaller drill and finish as you wish.
Have fun, I hope this helps. Outstanding suggestions here from everyone. I would be interested to read what PAP would suggest on this subject. Most of my lathe work is with the two materials I mentioned.
SAT
If I remember right, you are running a vintage South Bend. This lends itself to trial and error a bit. With a lantern tool post, you could make a boring bar from a chipped-tooth old tap by grinding the tap very slow and keeping the water handy for cooling. I'm guessing you are using 6061 T4 or T6 aluminum round bar or C1018 Cold Rolled Steel. Both have fairly low machinability numbers and are pretty friendly. For each material, hone any High Speed Steel boring bar (tap re-ground) or lantern tool post tool bit with a medium and fine grit diamond hone till they are really sharp, fingernail test. That, along with some Cool Tool II for lubrication and cooling should improve your results. With Carbide, your slower lathe should produce an acceptable finish. This has been my experience with my 1939 Sheldon overhead leather belt drive 10 X26 lathe running at a whopping 508 rpms. Drill to depth with a smaller drill and finish as you wish.
Have fun, I hope this helps. Outstanding suggestions here from everyone. I would be interested to read what PAP would suggest on this subject. Most of my lathe work is with the two materials I mentioned.
SAT