Drilling on the lathe

[jeff]

I had to laugh when I walked by this in the shop a few minutes ago. Looks just like what a lot of us do for pens, but the scale made me chuckle.

That's a 3" HSS bit in 7" diameter 304 stainless at 38 RPM. Those are some deadly chips! This will eventually be a jet engine exit nozzle for testing in our Acoustic Test Facility

 

[pshrynk]

Do you use a Roller Ball or Ball Point on that?

 

[FGarbrecht]

Do you use a Roller Ball or Ball Point on that?

Neither, that's a fountain pen

 

[FGarbrecht]

That looks scary. Had two lathe drill accidents recently, one bent a 7mm bit and sent it flying across my basement, the other my hand slipped off the chuck and the bit took a chunk out of my hand.

 

[jeff]

It's not too intimidating at 38 RPM, but that's a lot of cutting force. It's a 30 HP machine and he stalled it once.

 

[skiprat]

Hey Jeff..... Can you send me a couple of off cuts of that stainless bar please....

 

[DrD]

That looks scary. Had two lathe drill accidents recently, one bent a 7mm bit and sent it flying across my basement, the other my hand slipped off the chuck and the bit took a chunk out of my hand.

I have a question, why would one want to hold the chuck when drilling on the lathe?

 

[Curly]

If the coolant nozzle wasn't there we wouldn't know if that rod wasn't a pen blank.

 

[Curly]

I have a question, why would one want to hold the chuck when drilling on the lathe?

Sometimes the taper holing the chuck into the tailstock will come loose from vibration and pull out. Maintaining some pressure against the tailstock keeps it from slipping.

 

[JimB]

I have a question, why would one want to hold the chuck when drilling on the lathe?

Mostly because when you back it out, if the bit grabs, it can pull your entire chuck out of the tail stock. If you are holding the drill chuck you can prevent this from happening and you will also know instantly if it is starting to happen. If you are not holding it and this happens things can get very exciting very fast.

 

[Alan Morrison]

Who gets to sharpen that drill bit?

 

[DrD]

Thanks Pete & Jim! Makes sense.

Don

 

[WriteON]

I have a question, why would one want to hold the chuck when drilling on the lathe?

Absolutely a bad and dangerous thing to do.

 

[FGarbrecht]

Sometimes the taper holing the chuck into the tailstock will come loose from vibration and pull out. Maintaining some pressure against the tailstock keeps it from slipping.

Exactly. My chuck sometimes slips in the tailstock, especially when things get hot and the wood grabs the drill bit.

 

[WriteON]

Holding the chuck. Show us where the manufacturer says HOLD the chuck while turning. Your hands guys. Your fingers. I lost the tail stock chuck a few times. Simply hit the off switch and backed off.

 

[John Eldeen]

Holding the chuck. Show us where the manufacturer says HOLD the chuck while turning. Your hands guys. Your fingers. I lost the tail stock chuck a few times. Simply hit the off switch and backed off.

I think there my be some misunderstanding here Frank. The chuck I reference here is the drill chuck in the tail stock not the headstock. Pete and Jim have covered it really well

Mostly because when you back it out, if the bit grabs, it can pull your entire chuck out of the tail stock. If you are holding the drill chuck you can prevent this from happening and you will also know instantly if it is starting to happen. If you are not holding it and this happens things can get very exciting very fast.

Sometimes the taper holing the chuck into the tailstock will come loose from vibration and pull out. Maintaining some pressure against the tailstock keeps it from slipping.

 

[jeff]

Who gets to sharpen that drill bit?

We send them out for sharpening. The machinist spent about an hour touching it up with a stone before the operation. Most big boring is done with dedicated boring tools with carbide inserts, but sometimes our guys like to be a little old school.

 

[WriteON]

I think there my be some misunderstanding here Frank. The chuck I reference here is the drill chuck in the tail stock not the headstock. Pete and Jim have covered it really well

Is this what we are discussing?

 

[John Eldeen]

Is this what we are discussing?

Yes that is.

 

[WriteON]

Yes that is.

Hi. I will fold after this post. Just my opinion but I stick to my rules of operating machinery. Some of us can make our own rules or do things accordingly. I'm just stating my case as I'm never squeamish about safety. We're all buddies here. Not trying to go against the grain. Peace & out.

 

[sbwertz]

It gets real exciting when the chuck backs out of the tailstock when you pull it out. This is not such an issue if you are cranking it out with the tailstock crank, but if you are drilling by hand pushing the bit into the wood and pulling it back out manually, if the chuck comes out of the tailstock you have a bent bit and a heavy chuck flying around in an orbit before it breaks the wood and goes flying around the shop. I don't hold it while I'm drilling but I always hold it when I pull it out of the wood.