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View Full Version : Tail Stock: To Lock or Not to Lock



brendan stemp
9th Oct 2012, 03:32 PM
That is the question.

I was reminded of this dilemna; (ie should we, when spindle turning, lock the spindle) when I had Damo (work experience student) with me. He had obviously had some woodturning instruction from school and was always locking the spindle on the tail stock. I don't as a general rule. I have never found the need to; never thought it necessary.

So what do others do. And if you do lock the spindle, why? Has anyone had some excitement because they didn't.

turnerted
9th Oct 2012, 04:18 PM
I think it must depend on the lathe. On my Vicmarc I have rarely found it necssary. When I demonstrate on the clubs oldish midi woodfast,if I don't lock it, it comes loose.
Ted

RETIRED
9th Oct 2012, 04:38 PM
Depends on circumstances and condition of quill.

Some clubs have such worn ones that if you don't lock it they move sideways.

If there is vibration I lock the quill but if all is running well I don't bother.

I always tell students to lock it.

Tim the Timber Turner
9th Oct 2012, 06:17 PM
I'm with on this one (again).

If you position the handle on the tailstock hand wheel in the 1 o'clock to 5 o'clock position the weight of the handle will maintain tension on the work without locking the quill.

If you position it on the other side of the handwheel it can work loose as the handle drops anticlockwise to the 6 o'clock position.

If it's vibrating lock it up.

Cheers

Tim:)

vk4
9th Oct 2012, 11:21 PM
My MC900, will loosen off , regardless of what I am turning unless I lock the spindle, then these are an economy lathe, but I was always taught to lock the spindle , for safety.

Jeff
vk4

rodent
9th Oct 2012, 11:53 PM
I always lock the spindle except when drilling of course but that's because i don't like flying bits of timber trying to attack me .

swk
10th Oct 2012, 12:34 AM
FWIW I was trained up in metal working lathes as a young un and have always locked the tailstock and spindle, wood or metal lathe. Never thought to do otherwise.

Regards
SWK

Paul39
10th Oct 2012, 04:04 AM
I always lock the spindle except when drilling of course but that's because i don't like flying bits of timber trying to attack me .

AGREED!!

I do lots of out of balance bowl blanks. Sometimes even at the slowest speed the lathe and bench are shaking like a dog pooping peach seeds. I lock everything and check twice, run the lathe standing to the side, re tighten and continue.

dr4g0nfly
10th Oct 2012, 07:49 AM
Like everyone else I'm with .

When I got my new lathe it only had on rest (14") so small pieces meant I had the quill well extended, and boy could it vibrate without being locked.

Now I've had a couple of shorter ones made it's not so important, but out of balance pieces, I lock down, just to be sure.

brendan stemp
10th Oct 2012, 08:07 AM
If you position the handle on the tailstock hand wheel in the 1 o'clock to 5 o'clock position the weight of the handle will maintain tension on the work without locking the quill.

If you position it on the other side of the handwheel it can work loose as the handle drops anticlockwise to the 6 o'clock position.

If it's vibrating lock it up.

Cheers

Tim:)

Very interesting point; thanks TtTT

Also thanks to all the others that responded. It appears from these that the main reason the quill might back off is due to vibration of the lathe. That makes sense to me. Also, perhaps the quality of the lathe/quill. I know some lathes have better cut threads on the quill than others.

Rod Gilbert
10th Oct 2012, 08:08 AM
Why not lock it?
Regards Rod.:?

RETIRED
10th Oct 2012, 08:43 AM
Why not lock it?
Regards Rod.:?In my case it is speed.

We are production turners and every second that you save is money in the bank. Having to move or undo something costs time.

Our timber is usually all machined and evenly weighted so vibration is generally not an issue.

On the larger stuff the lock is always put in and I advise all others to do the same.

A case of do as I say not as I do.:wink:

hughie
10th Oct 2012, 08:51 AM
Some clubs have such worn ones that if you don't lock it they move sideways.
If there is vibration I lock the quill but if all is running well I don't bother.




I agree, but one of the reasons for a quill lock is to prevent any movment during operation and one of the fastest ways to increase your slop in the quill is to turn with it unlocked, Ok it will take a fair while for this to occur. But even if you have a nice piece running true and in balance, As your turning you will apply side pressure to the quill and vibration if only fine vibration. As I mentioned it wont happen over night but it will happen, on engineering lathes you always lock the spindle with centre turning mainly for accuracy but also to prevent damage to the quill.



We are production turners and every second that you save is money in the bank. Having to move or undo something costs time.



This is just a simple commercial decision, time is money versus a small amount of wear, time wins out everytime. Anyway by the time the quill is stuffed several other parts will be on the way out and the lathe has reached its use by date.

chambezio
10th Oct 2012, 10:38 AM
In my case sometimes I do some times I don't (maybe because I forget to) Sometimes I will get a vibration so I will go through all the potential places to stop it only to find a little nip up of the tail stock handle will fix it. I don't think there is a right or wrong its just depends on what you feel comfortable with. Just to off set your thinking.....when you use a metal cut off saw.....do you clamp the piece being cut or hold on to the offcut until you complete the cut???? Being a "woodman first" I mostly hold the the steel by hand without using the vice. Only sometimes I have had a jamb up but so far (30 plus years) I have never had a really dangerous problem. What do others do?

Jim Carroll
10th Oct 2012, 11:16 AM
As with all things it is about safety.

There is generally some form of vibration on the lathe and it does not take much for the quill to back of slightly and the live centre looses drive then you get this peice spiraling to you.

It is more common with those that just use a cone centre as this is the least amount of grip.

The safer way is to use a cup centre or a pin and ring style or even safer is the steb centre as the spring loaded pin give a bit more drive when things come loose.

So lock the tailstock in position then adjust the quill and tighten, run for a moment and nip up as some timbers with the lateral load embed themselves a bit more in the spur drive and this them gives the tailstock less running pressure.


This brings us to the next question on how to use the spur drive properly.
We find that most people put the spur drive into the headstock and rely on tailstock pressure, this is not enough for a good purchase on the wood.

It is best to have a second spur drive that you use as a punch off the lathe.
You mark your centre then use your spare spur drive as a punch and hit the end of the spur drive into the end of the peice of wood with a good thump, this is why it is your spare drive as over time the taper will mishape slightly and be of no use the the headstock taper. This gives you deeper indents than just using tailstock pressure.
You then bring the peice of wood to the lathe and locate the wood into the marks left by the spur drive and then bring up the tailstock, this gives maximum insertion in the wood and you are not relying on the tailstock to push into the wood.

This is what safety is all about and anyone teaching should be puting safety first before you start turning.

oreos40
10th Oct 2012, 02:13 PM
In my case it is speed.

We are production turners and every second that you save is money in the bank. Having to move or undo something costs time.

Our timber is usually all machined and evenly weighted so vibration is generally not an issue.

On the larger stuff the lock is always put in and I advise all others to do the same.

A case of do as I say not as I do.:wink:

For speed and high production there is nothing that chucks up faster and more positively than a lever action over center tailstock. It cant vibrate loose! often peices can be changed without shutting the machine off.

RETIRED
10th Oct 2012, 03:21 PM
For speed and high production there is nothing that chucks up faster and more positively than a lever action over center tailstock. It cant vibrate loose! often peices can be changed without shutting the machine off.Couldn't agree more.

joe greiner
11th Oct 2012, 12:03 AM
As with all things it is about safety.

There is generally some form of vibration on the lathe and it does not take much for the quill to back of slightly and the live centre looses drive then you get this peice spiraling to you.

It is more common with those that just use a cone centre as this is the least amount of grip.

The safer way is to use a cup centre or a pin and ring style or even safer is the steb centre as the spring loaded pin give a bit more drive when things come loose.

So lock the tailstock in position then adjust the quill and tighten, run for a moment and nip up as some timbers with the lateral load embed themselves a bit more in the spur drive and this them gives the tailstock less running pressure.


This brings us to the next question on how to use the spur drive properly.
We find that most people put the spur drive into the headstock and rely on tailstock pressure, this is not enough for a good purchase on the wood.

It is best to have a second spur drive that you use as a punch off the lathe.
You mark your centre then use your spare spur drive as a punch and hit the end of the spur drive into the end of the peice of wood with a good thump, this is why it is your spare drive as over time the taper will mishape slightly and be of no use the the headstock taper. This gives you deeper indents than just using tailstock pressure.
You then bring the peice of wood to the lathe and locate the wood into the marks left by the spur drive and then bring up the tailstock, this gives maximum insertion in the wood and you are not relying on the tailstock to push into the wood.

This is what safety is all about and anyone teaching should be puting safety first before you start turning.


I agree that tailstock pressure is insufficient for engagement. But I'm not too keen on using a spare spur drive, because of infinitesimal variations in shape. Even within the spur drive, spurs can vary because of manufacturing tolerance. So if remounting is at all potential, I mark its position on the wood - referring to a scratched mark on the drive, or the setscrew socket on replaceable points.

To avoid distortion of the taper, I use a leather-faced mallet to thump into position, and/or several thumps to assist alignment. Never touch it with a metal instrument.

Cheers,
Joe

Pat
11th Oct 2012, 04:43 AM
As with all things it is about safety.

There is generally some form of vibration on the lathe and it does not take much for the quill to back of slightly and the live centre looses drive then you get this peice spiraling to you.

It is more common with those that just use a cone centre as this is the least amount of grip.

The safer way is to use a cup centre or a pin and ring style or even safer is the steb centre as the spring loaded pin give a bit more drive when things come loose.

So lock the tailstock in position then adjust the quill and tighten, run for a moment and nip up as some timbers with the lateral load embed themselves a bit more in the spur drive and this them gives the tailstock less running pressure.


This brings us to the next question on how to use the spur drive properly.
We find that most people put the spur drive into the headstock and rely on tailstock pressure, this is not enough for a good purchase on the wood.

It is best to have a second spur drive that you use as a punch off the lathe.
You mark your centre then use your spare spur drive as a punch and hit the end of the spur drive into the end of the peice of wood with a good thump, this is why it is your spare drive as over time the taper will mishape slightly and be of no use the the headstock taper. This gives you deeper indents than just using tailstock pressure.
You then bring the peice of wood to the lathe and locate the wood into the marks left by the spur drive and then bring up the tailstock, this gives maximum insertion in the wood and you are not relying on the tailstock to push into the wood.

This is what safety is all about and anyone teaching should be puting safety first before you start turning.

For marking center, I thump the ends with a Vicmarc Drive Dog Punch (http://www.cws.au.com/shop/item/vicmarc-drive-dog-punch). No need to worry about deforming the taper, just don't drop the blessed thing on you toes:;

tea lady
11th Oct 2012, 08:14 AM
This brings us to the next question on how to use the spur drive properly.
We find that most people put the spur drive into the headstock and rely on tailstock pressure, this is not enough for a good purchase on the wood.

It is best to have a second spur drive that you use as a punch off the lathe.
You mark your centre then use your spare spur drive as a punch and hit the end of the spur drive into the end of the peice of wood with a good thump, this is why it is your spare drive as over time the taper will mishape slightly and be of no use the the headstock taper. This gives you deeper indents than just using tailstock pressure.
You then bring the peice of wood to the lathe and locate the wood into the marks left by the spur drive and then bring up the tailstock, this gives maximum insertion in the wood and you are not relying on the tailstock to push into the wood.

This is what safety is all about and anyone teaching should be puting safety first before you start turning.Sometimes you don't want a big ding in your wood as you need to adjust it in teh lathe to make sure your pomel it square. Which may not be the same as being square with the end of the bit of wood.:S

Jim Carroll
11th Oct 2012, 09:26 AM
Sometimes you don't want a big ding in your wood as you need to adjust it in teh lathe to make sure your pomel it square. Which may not be the same as being square with the end of the bit of wood.:S

If the timber is dressed properly this should not be a problem :D

Tim the Timber Turner
11th Oct 2012, 11:24 AM
Iím with Ann Marie on this one.

Just because the wood has been machined doesn't mean it will run true at the transition points (pommel).

There can be a number of reasons for this, poor machining, moisture content, incorrect storage or it just might be a twisty bit of wood that moved after machining.

Using a spring loaded centre punch or punching a drive centre into endgrain of Pinus Twistus is problematic if you hit the hard winter growth ring.

The hard winter growth ring can kick the point off to one side.

Drilling a shallow 3mm hole will help overcome this.

I have used the Vicmarc drive dog punch but it is really only a good fit for the Vicmarc drive centre.

I use this method for driving large diameter (150mm) hardwood posts.

For sizes around 75 or 100mm I like to use a 32mm Steb centre and a smaller steb live centre.

It's easy to adjust the centres if the work doesnít run true.

Cheers

Tim:)

TTIT
11th Oct 2012, 12:44 PM
For marking center, I thump the ends with a Vicmarc Drive Dog Punch (http://www.cws.au.com/shop/item/vicmarc-drive-dog-punch). No need to worry about deforming the taper, just don't drop the blessed thing on you toes:;I looked at getting one of those once and found the drive dogs are about $20 cheaper :o Far better off just buying two drive dogs and using one for a punch :;

chuck1
12th Oct 2012, 06:57 PM
The only time I lock my tail stock is when I'm turning cabriole legs, but don't when turning balustrades to save time! but I advise students to when teaching for safety until their confidence grows.

tea lady
12th Oct 2012, 07:00 PM
If the timber is dressed properly this should not be a problem :Damazing how bendy a verandah post can be and still LOOK straight.:D

Jim Carroll
12th Oct 2012, 07:52 PM
amazing how bendy a verandah post can be and still LOOK straight.:D

Now you are talking real spindle turning:2tsup: