Locking spindle on a 10" Logan Lathe?

Hi All,
What is the correct way to lock up the spindle on a 10" Logan/Wards lathe so as to remove a chuck, or put one on?
It seems to me that the only way do do this is to engage the back gears w ithout pulling the lock pin on the bull gear. It occurs to me that the da nger in doing this when I spin the chuck on, or give it a little rap to rem ove it, is that I am putting that same force on the teeth of the bull gear or the back gears.
This is an old lathe, and I've already lost two teeth on the bull gear o ver the years, so I would like to find a better way to lock the spindle. A re there any accessories or hardware solutions that are "bolt on" options f or the Logan lathe?
Thanks,
Dan
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Hi All,
What is the correct way to lock up the spindle on a 10" Logan/Wards lathe so as to remove a chuck, or put one on?
It seems to me that the only way do do this is to engage the back gears without pulling the lock pin on the bull gear. It occurs to me that the danger in doing this when I spin the chuck on, or give it a little rap to remove it, is that I am putting that same force on the teeth of the bull gear or the back gears.
This is an old lathe, and I've already lost two teeth on the bull gear over the years, so I would like to find a better way to lock the spindle. Are there any accessories or hardware solutions that are "bolt on" options for the Logan lathe?
Thanks,
Dan
For starters, DO NOT spin the chuck onto the spindle under power! Just bump it on by hand. Then it'll be much easier to remove. phil k.
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Hi All,
What is the correct way to lock up the spindle on a 10" Logan/Wards lathe so as to remove a chuck, or put one on?
It seems to me that the only way do do this is to engage the back gears without pulling the lock pin on the bull gear. It occurs to me that the danger in doing this when I spin the chuck on, or give it a little rap to remove it, is that I am putting that same force on the teeth of the bull gear or the back gears.
This is an old lathe, and I've already lost two teeth on the bull gear over the years, so I would like to find a better way to lock the spindle. Are there any accessories or hardware solutions that are "bolt on" options for the Logan lathe?
Thanks,
Dan
======================= That question has a painful tainted history on r.c.m., after a poster suggested how to apply an impact wrench to the spindle. I don't recall anyone offering a good non-destructive answer.
If the chuck isn't too tight a strap wrench around the largest pulley step may help. The coyote answer is to cut off and replace the backplate.
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On 10/17/2018 11:56 AM, Jim Wilkins wrote:

has 2 suggestions for removing a chuck . Either chuck a piece of hex stock in it and use a box end wrench to PULL to loosen , or fit a crescent wrench to one of the jaws to do the same (with back gear and direct both engaged) . It's the shock load that breaks teeth - I use a crescent wrench myself .
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    Sounds like you are referring to Altavoz's posting. I never saw that posting, as I seem to have joined here shortly after he posted that.

    Another approach is to take an appropriate length of 2x4, put it between a jaw on the back side of the spindle and the lathe bed, and engage the motor in reverse with the back-gear engaged to unscrew the chuck.
    On my Clausing (12x24") I replaced the 2-1/4x8 spindle with a L-00 spindle, and have had no problems since then. (Of course -- also new backplates for the chucks were needed.)
    Enjoy,         DoN.
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Personally I wouldn't subject a leather belt drive to that much shock. I keep mine loose enough to slip before something else breaks.
The only task that has made a chuck difficult to unscrew is turning a square blank round. If I bandsaw the blank octagonal there's less temptation to speed up the job with a heavy interrupted cut. -jsw
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    Well ... my lathe has three parallel V-belts from idler shaft to spindle, and one bigger V-belt from motor to idler.
    And I wasn't talking about shock. Rotate the chuck so a jaw is holding the 2x4 between it and the back of the bed.
    With flat leather belts, do the same, but let it slip a bit as you start the motor, and then adjust the slip out.

    Granted, it is an extreme condition.
    Chips in the spindle nose threads, or those in the chuck can cause the locked chuck. The _How to Use A Lathe_ book (either the SouthBend or the Atlas one, I forget which, has a drawing of a spring-loaded bit of wire with chisel ends to clean chips out of the internal threads in the chuck or the chuck backplate. A wire brush on the spindle nose helps there, too.
    Also -- a loose chuck on the spindle when you turn on the motor can lock itself in place when the spindle runs up into the chuck backplate.
    I've never had to turn off the backplate on a locked spindle, though that is something to keep in reserve just in case.
    But I do very much prefer the L-00 spindle nose and backplate.
    Enjoy,         DoN.
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On Wednesday, October 17, 2018 at 10:42:20 AM UTC-4, snipped-for-privacy@vadiodes.com wr ote:

he so as to remove a chuck, or put one on?

without pulling the lock pin on the bull gear. It occurs to me that the danger in doing this when I spin the chuck on, or give it a little rap to r emove it, is that I am putting that same force on the teeth of the bull gea r or the back gears.

over the years, so I would like to find a better way to lock the spindle. Are there any accessories or hardware solutions that are "bolt on" options for the Logan lathe?

Thanks all!
I guess I'll just have to be careful. For the record, I never spin the chu cks on under power. Usually I thread them carefully, then give it a quick spin by hand for the last 1/4 turn or so. Maybe I'll just seat it gently b y hand.
As for removal, I usually put the key wrench in the side and pull. I've ne ver had to bang hard on them, but if the chuck doesn't come off easily, I'l l do as suggested and use a crescent wrench in some hex stock.
I do wish there were a relatively easy way to lock up the spindle without p utting force on the teeth. One thing that could possibly work is a wood p iece that fits in above the bull gear and wedges between the front and back of the head-stock casting. There would be a semi-circle of wood covering the top half of the bull gear. But I would use some epoxy to case "teeth" into that part that mate with the bull gear and hold it fast. That way, th e force would be distributed over many teeth. I don't know if it's worth the effort though, or if it will work, but it would have the advantage that I could "index" my spindle by pulling out the block and rotating it by one or more teeth.
Thanks again for the advice. Dan
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On Friday, October 19, 2018 at 3:15:08 PM UTC-4, snipped-for-privacy@vadiodes.com wrote:
wrote:

athe so as to remove a chuck, or put one on?

rs without pulling the lock pin on the bull gear. It occurs to me that th e danger in doing this when I spin the chuck on, or give it a little rap to remove it, is that I am putting that same force on the teeth of the bull g ear or the back gears.

ar over the years, so I would like to find a better way to lock the spindle . Are there any accessories or hardware solutions that are "bolt on" optio ns for the Logan lathe?

hucks on under power. Usually I thread them carefully, then give it a quic k spin by hand for the last 1/4 turn or so. Maybe I'll just seat it gently by hand.

never had to bang hard on them, but if the chuck doesn't come off easily, I 'll do as suggested and use a crescent wrench in some hex stock.

putting force on the teeth. One thing that could possibly work is a wood piece that fits in above the bull gear and wedges between the front and ba ck of the head-stock casting. There would be a semi-circle of wood coverin g the top half of the bull gear. But I would use some epoxy to case "teeth " into that part that mate with the bull gear and hold it fast. That way, the force would be distributed over many teeth. I don't know if it's wort h the effort though, or if it will work, but it would have the advantage th at I could "index" my spindle by pulling out the block and rotating it by o ne or more teeth.

Interesting idea, but probably unnecessary, as its the shock that breaks te eth, not (usually) a steady load. Scott Logan suggested (for very stuck chu cks) placing a longish length of 2x4 between jaws and steadily pulling on t he end of the 2x4. The danger here is having too much leverage and tipping the lathe over. In extreme cases, you'll need to secure the lathe.
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