Author Topic: Lathe dogs.  (Read 13806 times)

Offline George Greer

  • Jr. Member
  • **
  • Posts: 17
Lathe dogs.
« on: May 10, 2010, 11:51:11 PM »
Ok, here starts the beginnings  of many questions.

Can someone post a photo of lathe dogs in use?  I have a chance to get a set of them (free)....and wondering if I would ever use them.

Cheers,  :beer:

George

Offline cedge

  • Madmodder Committee
  • Sr. Member
  • *****
  • Posts: 327
Re: Lathe dogs.
« Reply #1 on: May 11, 2010, 12:56:14 AM »
George....
Get them.... You'll use them from time to time.

Steve

Offline John Hill

  • The Artful Bodger
  • Madmodder Committee
  • Hero Member
  • *****
  • Posts: 2016
  • Country: nz
Re: Lathe dogs.
« Reply #2 on: May 11, 2010, 02:11:20 AM »
George, here is one of them in use when turning between centres.

From the den of The Artful Bodger

Offline sbwhart

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 3530
  • Country: gb
  • Smile, Be Happy, Have Fun and Rock Until you Drop
Re: Lathe dogs.
« Reply #3 on: May 11, 2010, 11:36:42 AM »
George they can be very handy I'd get them.

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

Location:- Crewe Cheshire

Offline George Greer

  • Jr. Member
  • **
  • Posts: 17
Re: Lathe dogs.
« Reply #4 on: May 11, 2010, 10:29:47 PM »
Thanks for the replys.

I actually feel kinda bad about taking them.

I will explain, once I showed an interests in learning about machining, quite a few people have given me a lot of items, to help get me along, and a good bit of advice about machining in general.

In a couple of days, I will attach a couple of photos to show what I mean.

George

Offline snub

  • Full Member
  • ***
  • Posts: 151
  • Country: ca
  • Canada
Re: Lathe dogs.
« Reply #5 on: May 12, 2010, 10:16:48 PM »
George, here is one of them in use when turning between centres.


Is there any way to use lathe dogs with a regular three jaw chuck or do you need the slotted plate as shown in your photo? I seem to recall seeing a photo of a lathe dog being used in a chuck, but maybe the plate was mounted in the chuck. Do you have any more photos? I'm quite curious about this.

Thanks!

Offline Andrew_D

  • Jr. Member
  • **
  • Posts: 44
Re: Lathe dogs.
« Reply #6 on: May 13, 2010, 12:27:19 AM »
Is there any way to use lathe dogs with a regular three jaw chuck or do you need the slotted plate as shown in your photo? I seem to recall seeing a photo of a lathe dog being used in a chuck, but maybe the plate was mounted in the chuck. Do you have any more photos? I'm quite curious about this.

Yup....

First, center drill your stock as your normally would. (Don't forget to do this first!!!)

Now, mount a different piece of round stock in your three jaw chuck.
Turn a 60º point on the end with your compound. (This now becomes your "center". DO NOT remove the center from the chuck!!!)
Place the lathe dog on the stock to be turned.
Mount the stock between your new center and the center in your tailstock.
Brace one of the jaws on the 3-jaw chuck against the leg of the lathe dog.

If you remove your new center from the 3-jaw chuck, you will have to re-turn the 60º point on the end to ensure concentricity.

Andrew

Offline snub

  • Full Member
  • ***
  • Posts: 151
  • Country: ca
  • Canada
Re: Lathe dogs.
« Reply #7 on: May 13, 2010, 10:28:30 PM »
 ^ I'm assuming you would use this method for turning a tapered shaft?

Offline Bernd

  • Madmodder Committee
  • Hero Member
  • *****
  • Posts: 3688
  • Country: us
  • 1915 C Cab
    • Kingstone Model Works
Re: Lathe dogs.
« Reply #8 on: May 14, 2010, 08:35:57 AM »
Yes, it can be used for cutting a taper. The lathe dog is just another way to machine a round part in the lathe. It is not unique to doing a job only one way.

Bernd
Route of the Black Diamonds

Offline kvom

  • Hero Member
  • *****
  • Posts: 520
Re: Lathe dogs.
« Reply #9 on: May 14, 2010, 08:56:57 AM »
One advantage of using a lathe dog between centers is that you can remove the work from the lathe and later put it back without losing concentricity.

Offline Andrew_D

  • Jr. Member
  • **
  • Posts: 44
Re: Lathe dogs.
« Reply #10 on: May 14, 2010, 10:10:40 PM »
One advantage of using a lathe dog between centers is that you can remove the work from the lathe and later put it back without losing concentricity.

I tend to think that is the main advantage...
The only time I have turned between centers is when I know I'll be removing it for a test fit or maybe a second-op on the mill, and then need to put it back in the lathe. (Usually, I use a 3 or 4-jaw chuck and support the other end with the live center.)

Of course, using a dead center in the spindle instead of a center turned in a 3-jaw would (in most cases) result in being able to turn slightly longer shafts. Might be an issue on some lathes.

Andrew