what center drills for lathe?

[The Cobbler]

I am looking for some good quality center drills. I have some of my fathers that he got from work, and they are very good. others that I buy seem to be brittle & break very easily . they are so called high speed tool steel .
I am wondering if carbide drills would be any better? I see some on ebay , manufactured in USA
any recommendations appreciated

 

[kazlx]

I've always had good luck with KEO and they are super reasonable.

 

[Griff93]

The carbide ones are going to be more prone to break than hss.

 

[dogdog]

center drills ? for starting a hole ?but not normally for drilling drilling right ? how do you break them?

 

[BuffettFan]

2nd for KEO. I buy them from MSC.
As Griff93 said, carbide is more prone to breakage, they are less forgiving.
Is the problem only on your lathe?
If so, it sounds like the tailstock may be out of line with the chuck.
When I use them, I typically only go deep enough to start the chamfer, not to the full diameter of the center drill.

 

[OccupantRJ]

There are center drills, and there are combined drill and counter sinks, which most people seem to use on an engine lathe. We used center drills on our CNC equipment at work. Catalogs may sometimes use either term. I use HSS combined drill and countersink, and KEO seems to be a good tool.

 

[zmotorsports]

I switched over to this style of spotting drills a couple of years ago and prefer them to old standard center drills.

https://www.travers.com/high-speed-...KEO&lite=true&kcproxy=true&pricelistname=SITE

 

[The Cobbler]

Thanks for the tips and advice.
The ones my dad had are fine, I just wanted to add some to my collection so I can keep his in good shape.
The ones I break were off of eBay & Chinese, so I'm sure that's my problem.
will order some KEO

 

[kazlx]

It really depends if you are spotting for a drill or actually using for a center. If you are just spotting for a drill, I would use what Z said, just the stub spot drill. But either way works. If you are drilling to use a live center, then you would definitely need a center drill for clearance.

 

[larry_g]

It really depends if you are spotting for a drill or actually using for a center. If you are just spotting for a drill, I would use what Z said, just the stub spot drill. But either way works. If you are drilling to use a live center, then you would definitely need a center drill for clearance.

Quoted because it is important to know. You can use a center drill for spotting a hole to be drilled, but not a spotting drill for a lathe center. Selecting the right tool for the job and all that.....

lg
no neat sig line

 

[zmotorsports]

It really depends if you are spotting for a drill or actually using for a center. If you are just spotting for a drill, I would use what Z said, just the stub spot drill. But either way works. If you are drilling to use a live center, then you would definitely need a center drill for clearance.

Quoted because it is important to know. You can use a center drill for spotting a hole to be drilled, but not a spotting drill for a lathe center. Selecting the right tool for the job and all that.....

lg
no neat sig line

Agreed. I should have been more specific. I was understanding it that the OP was looking to drill but the ones I listed won't allow enough clearance for a live center.

 

[The Cobbler]

Live center, yes.
spot drill for drill bit, yes

 

[dr_clyde]

I use KEO, have been very happy with them.

 

[matt_i]

Re: alignment of the tailstock to the headstock/spindle. Cheap and easy way is to weld some sort of "clamp" to the OD of a piece of Sch 40 black pipe or a pipe fitting like a coupling. Roughly 1-1/2" OD.

Now clamp a test indicator to the pipe, clamp the pipe piece in the chuck, it does not have to be perfectly centered, you may use the 3 jaw chuck.

Indicate the ram of the tailstock while manually jogging the spindle, there's probably a "keyway" in the bottom of it but possibly it doesn't extend full length.

And now you know if you have alignment issues. The lathe where I work is bad to catch chips under the tailstock flat way that get partially embedded and now the tailstock sits high or pointing up slightly. I can tell because of the flex in a center drill. Once the swarf is removed it indicates and performs much better.

 

[Farrier]

I have never broken a center bit

 

[The Cobbler]

tailstock is in line with chuck within 1/2 thou.
the drills that gave me trouble were cheapies off of ebay, from China. they are very brittle and snap . the ones my dad had are fine.

 

[OhioRandy]

The angle on the center drill matches the angle on the live center in the tailstock. The angle on the stub drill is different. Very important to use center drill when wanting to use live center. Not so important when doing a drill start.

 

[theoldwizard1]

Drill Hog

 

[laser3kw]

I have never broken a center bit

ditto.
I am about as hard on tooling as it gets and have never broken one. Dulled the **** out of them and render them useless, yea, I've done that.
Also, don't confuse "center drill" with "spot drill". Each has different point angles.

 

[sanddan]

I switched over to this style of spotting drills a couple of years ago and prefer them to old standard center drills.

https://www.travers.com/high-speed-...KEO&lite=true&kcproxy=true&pricelistname=SITE

That's what I use unless I can use a stubby drill instead. Stubby drill, or screw machine drill is great when the job allows using a short drill instead of the standard jobber length.

https://www.travers.com/stub-screw-machine-twist-drills/p/425731/?lite=true&pricelistname=SITE