Author Topic: Chuck Balancing......  (Read 7234 times)

Offline Stilldrillin

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Chuck Balancing......
« on: November 07, 2011, 12:55:22 PM »
The 80mm chuck on my 7 x 12 lathe was much too small. So, I replaced it with a 4" adaptor and chuck.......  :thumbup:

Most of the time, it was all I needed, even if it did vibrate at certain revs.......  :scratch:

Some time later, I remembered, I used to balance 24" grinding wheels!   

Similar method to this, lash up.......




3off, 1/2" dia brass bars. Two, positioned horizontal, and parallel to each other.
The other gripped by the chuck......




Drill out 8mm holes from the low point, until it will rest in any position.

Looks rather dramatic, back in it's place.......




Made a very big difference to the feel of the machine.  :D

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline rleete

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Re: Chuck Balancing......
« Reply #1 on: November 07, 2011, 02:10:13 PM »
You just like to drill holes in things...
Creating scrap, one part at a time

Offline Stilldrillin

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Re: Chuck Balancing......
« Reply #2 on: November 07, 2011, 02:19:24 PM »
You just like to drill holes in things...

Ohh...... YES!  :thumbup:
Sometimes..... I even get 'em in the right place, too!  :D

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline Jasonb

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Re: Chuck Balancing......
« Reply #3 on: November 07, 2011, 02:34:07 PM »
Does the position of the scroll not affect the balance? would be interested how it balances with the jaws opened 1/3 & 2/3 of a revolution. And whats it like with the outside jaws now.

J

Offline sbwhart

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Re: Chuck Balancing......
« Reply #4 on: November 07, 2011, 03:12:03 PM »
Thats an interesting solution

I wonder why it was out of balance in the first place, I notice you,ve drilled the holes about oposite the chester badge on the front face whats under the badge and how deep does its hole go  ?.

I've got a chesters chuck mine seems ok, I wonder if you got a Monday morning one.

Puzzled

Stew
A little bit of clearance never got in the road
 :wave:

Location:- Crewe Cheshire

Offline HS93

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Re: Chuck Balancing......
« Reply #5 on: November 07, 2011, 04:31:41 PM »
Just a question , could you have drilled the holes in the back plate or would that not have worked as well, ?

Peter
I am usless at metalwork, Oh and cannot spell either . failure

Offline doubleboost

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Re: Chuck Balancing......
« Reply #6 on: November 07, 2011, 05:09:47 PM »
Nicely done David
I like your bed protector as well
Been going to make one for years
John

Offline Stilldrillin

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Re: Chuck Balancing......
« Reply #7 on: November 07, 2011, 06:02:24 PM »
Thanks for your comments, Chaps!  :thumbup:

Jason,

I never thought of the scroll position making much difference, compared to the mass of the body casting.

But, I spun it up in the lathe with the jaws set at several different diameters, also with the outside jaws.
There were variations of slight vibration, but nothing like there had been.

Stew,

I wondered at the time of fitting, if it was right, like that. But it never changed in it's accuracy.
So, I just accepted, that's how it was.......

My lathe is much lighter, and more sensitive to out of balance forces than yours. (I guess)!

Peter,

The adaptor is steel. With only the two, three hole stud patterns. I assumed it would be "self balanced". (As in, no casting flaws).......
The drilled area is the only part with any thickness of material, which could have an inclusion.

Thanks John,
The protector is only a piece of old t&g floor boarding. But it's saved the bed several times, when my fumbly fingers have let go.......


The chuck arrived in Scotland this afternoon. Perhaps the new owner might have some comment to make.......

More drilling to  follow.......

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline DaveH

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Re: Chuck Balancing......
« Reply #8 on: November 07, 2011, 10:38:08 PM »
David,

Just wondering does it (by any chance) hum as it goes round :palm: :palm: :palm:

 :beer:
DaveH
(Ex Leicester, Thurmaston, Ashby De La Zouch.)

Offline Stilldrillin

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Re: Chuck Balancing......
« Reply #9 on: November 08, 2011, 02:30:04 AM »
David,

Just wondering does it (by any chance) hum as it goes round :palm: :palm: :palm:

 :beer:
DaveH

It's Chinese Dave....... Not heard anything I can recognise!  :lol:


That little experiment set me up to tackle the next step.... A 125mm assembly.

The cast backplate, has the three and four hole patterns sharing a common hole. A long way out of balance........

With backplate only mounted, the lathe bounced!  :palm:

I mounted on a plastic plug.........




And started drilling......




The two central holes, go down to the spigot diameter! The lathe now, (backplate only), is super smooth, up to it's max of 2,500.


Before mounting the brand new chuck, I decided to strip, clean and grease. Very pleased I did!

This was the residue in the wash container.......




The new assembly runs very nicely. I'll let the grease settle for a few sessions, before any more hole drilling.....



David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline Davo J

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Re: Chuck Balancing......
« Reply #10 on: November 08, 2011, 09:09:57 AM »
Just a question , could you have drilled the holes in the back plate or would that not have worked as well, ?

Peter

Hi,
Peter can correct me if I am wrong, but I think he meant drilling the back plate instead of the chuck.

I know the job is done now, but just a thought for next time,
For both jobs would you have been able to to drill the face or the back plate for balance? Then they would be unseen once the chuck was bolted to it. The small loss of surface area for the chuck to sit on the back plate wouldn't have hurt anything.


Dave

Offline Stilldrillin

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Re: Chuck Balancing......
« Reply #11 on: November 08, 2011, 10:22:27 AM »
Just a question , could you have drilled the holes in the back plate or would that not have worked as well, ?

Peter

Hi,
Peter can correct me if I am wrong, but I think he meant drilling the back plate instead of the chuck.

I know the job is done now, but just a thought for next time,
For both jobs would you have been able to to drill the face or the back plate for balance? Then they would be unseen once the chuck was bolted to it. The small loss of surface area for the chuck to sit on the back plate wouldn't have hurt anything.

Dave

Hi Dave.
My thoughts were.... The chuck was at fault, not the backplate.... Fix the chuck!

Never thought of drilling the cast backplate t'other direction!  :scratch:
It would have been neater.... TUT!! :palm:

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline HS93

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Re: Chuck Balancing......
« Reply #12 on: November 08, 2011, 10:54:33 AM »
Just a question , could you have drilled the holes in the back plate or would that not have worked as well, ?

Peter

Hi,
Peter can correct me if I am wrong, but I think he meant drilling the back plate instead of the chuck.

I know the job is done now, but just a thought for next time,


For both jobs would you have been able to to drill the face or the back plate for balance? Then they would be unseen once the chuck was bolted to it. The small loss of surface area for the chuck to sit on the back plate wouldn't have hurt anything.


Dave

Yes they where my thoughts but as I am am not a metalworker by trade I thought I would ask the question, as chucks can be moved about during there life and now its balanced for that backplate only.

Peter
I am usless at metalwork, Oh and cannot spell either . failure

Offline John Hill

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Re: Chuck Balancing......
« Reply #13 on: November 11, 2011, 09:35:43 PM »
Now you can turn little aluminium plugs to go in those holes! Of course it will be off balance again but you can always drill and plug more holes until it is balanced again. :lol:
From the den of The Artful Bodger

Offline Stilldrillin

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Re: Chuck Balancing......
« Reply #14 on: November 12, 2011, 02:12:09 AM »
Good idea John!  :clap:

I could drill the alloy plugs, to lighten them.......  :thumbup:

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline John Hill

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Re: Chuck Balancing......
« Reply #15 on: November 12, 2011, 04:41:52 AM »
Good idea John!  :clap:

I could drill the alloy plugs, to lighten them.......  :thumbup:

David D

Make hollow alloy plugs! :lol:
From the den of The Artful Bodger

Offline Lykle

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Re: Chuck Balancing......
« Reply #16 on: December 05, 2011, 10:35:18 AM »
No, just drill another hole next to the existing ones to balance out the alu. Simple.
But then you have to fill that one again, and then balance... oh well.
Lykle

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