How not to drill a pen blank or turning your jacobs chuck into a hammer!

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And one hand on chuck (1978)
We didn't get the gloved hand bit. Standard was nothing on the arms below the elbows, nothing. That and tie tucked in the shirt, i.e. no loose clothing.
Of course there was "If the chuck starts spinning do not withdraw the quill, or tailstock, at least until the lathe stops spinning."
geoff
 
This would lean into my arguement for having a foot kill switch. If it is all going wrong and you are trying to hold the chuck (probably with your left hand) and holding the tailstock with the right it is pretty difficult to lean over into the dangerzone to hit the off switch which is on the drive side of every machine I've seen. Which hand would you even choose to let go with?

I made a simple extension lead with a big red kill button that i can use on all of my machines. much easier than fumbling for the off switch in a panic moment.

Also as mentioned a faceshield just makes so much sense.
 
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I have the incoming power supply routed through two switched cable outlets, one at the right hand end and one in the middle of the bench, the one on the end I can switch off when deep hole boring and the one in the middle I can reach easily when the headstock is turned. Cheap and effective.
 
Far safer to mount the chuck in the headstock and make a horizontal jig to hold the workpiece. Start with square stock and turn the piece after the hole is drilled.
 
The jig would need to be very adjustable to accept different sized squares and round pen blanks are common, they'd need to be held as well. It would also need to be extremely accurate as it would be moving - sometimes you've only a mil or two to play with. Most of us use the same set up but would have advanced the bit slowly with the quill and waited until the bit was through and the lathe switched off before withdrawing it. He was just careless.
 
The jig would need to be very adjustable to accept different sized squares and round pen blanks are common, they'd need to be held as well. It would also need to be extremely accurate as it would be moving - sometimes you've only a mil or two to play with. Most of us use the same set up but would have advanced the bit slowly with the quill and waited until the bit was through and the lathe switched off before withdrawing it. He was just careless.
Was he careless ? I only ask the question because what I saw on the clip was nothing more than a lack of (pretty basic) engineering 'knowse' coupled to a very obvious lack of any form of training /instruction. How many of us take the time to perform a simple 'kiss-test' when moving from say bowl work (especially if the headstock has been rotated) to spindle work. To perform a safe (and accurate) accurate drilling/boring task, axial alignment is the key to a successul outcome. If anything good is to come ot of this clip, it's the fact that it perfectly demonstates the amount of lateral movement that can be present in a tailsock that is not locked to the bed before drilling/boring commences ...
 
I don't leave it to chance.
 

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A lucky escape. My first impression at the start of the drilling was that the blank was turning much too fast. I was taught to not drill using a Jacob’s chuck at much more than 350-400 rpm. I tend to use even lower speeds, and continually withdraw to clear the drill flutes. I think it is a good idea to also keep hold of the Jacob.
 
Was he careless ? I only ask the question because what I saw on the clip was nothing more than a lack of (pretty basic) engineering 'knowse' coupled to a very obvious lack of any form of training /instruction. How many of us take the time to perform a simple 'kiss-test' when moving from say bowl work (especially if the headstock has been rotated) to spindle work. To perform a safe (and accurate) accurate drilling/boring task, axial alignment is the key to a successul outcome. If anything good is to come ot of this clip, it's the fact that it perfectly demonstates the amount of lateral movement that can be present in a tailsock that is not locked to the bed before drilling/boring commences ...
Basic lack of imagination. What could possibly go wrong being the important question, then look at how best to avoid it.
 
A lucky escape. My first impression at the start of the drilling was that the blank was turning much too fast. I was taught to not drill using a Jacob’s chuck at much more than 350-400 rpm. I tend to use even lower speeds, and continually withdraw to clear the drill flutes. I think it is a good idea to also keep hold of the Jacob.
Yes, I also thought the lathe speed was too high. As for the need to 'continually withdraw to clear the drill flutes', this is also an esential action but it needs to be performed by using the tailstock quill, NOT by sliding the tailstock backwards along the bed ways !
As an aside, I'm just wondering how long it will take for comments to be posted in reaction to your idea to 'keep hold of the Jacob' ....
 
Gmoop2
While I didn’t actually mention it, I, of course, would only withdraw the drill bit by turning the tail stock hand wheel. It would be madness to do it by dragging the tail stock along the bedway. I’ve never had a problem holding the Jacob as the drill withdraws.
D.
 

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