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John Stevenson
12-12-2009, 07:34 PM
Neat tool to aid single point threading.

http://madmodder.net/index.php?topic=2323.0

You will need to get close to the end when the testing part is done.

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dewat
12-12-2009, 07:58 PM
I followed that thread from the beginning, Bogs does some nice work.





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Optics Curmudgeon
12-12-2009, 08:13 PM
A clapper for the lathe!

Joe

MTNGUN
12-12-2009, 08:21 PM
I hope someday I'll have time to do projects like that. Sigh.

Thanks for the link, John.

DFMiller
12-12-2009, 08:32 PM
Wow that is slick.
I need to make or get one. With it I think even I could single point

Forrest Addy
12-12-2009, 10:01 PM
Nice but - all those photos. Why not a part and assembly drawing.

dp
12-12-2009, 11:35 PM
Nice but - all those photos. Why not a part and assembly drawing.

If I recall correctly the builder said he was working it out in his head first and drawings would follow a successful completion.

Forrest Addy
12-13-2009, 01:24 AM
dp I work the same way many times - designing by noodling around followed by a sketch. Maybe I shouldn't be so crtical. Those step by step photos are probably helpful.

dp
12-13-2009, 01:44 AM
dp I work the same way many times - designing by noodling around followed by a sketch. Maybe I shouldn't be so crtical. Those step by step photos are probably helpful.

Hell, I've seen you do it in person! :)

John Stevenson
12-13-2009, 08:16 AM
The you tube video is here because the actual forum is down at the moment.

http://www.youtube.com/watch?v=8JFdNaBD5GM

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clutch
12-13-2009, 08:44 AM
Neat, can't see the website but got to watch the video. Is the tool holder simply hinged at the back?

Btw, what is the foreign language that the lathe operator speaks? :p

John Stevenson
12-13-2009, 08:58 AM
Neat, can't see the website but got to watch the video. Is the tool holder simply hinged at the back?

Btw, what is the foreign language that the lathe operator speaks? :p

Yes it's hinged at the back and under the holder at the front is a lengthwise key that fits into a slot in the holder to locate it from wandering sideways.

The language is called "Down to earth middle english " :rolleyes:, actually Cheshire speak.

Timleech
12-13-2009, 09:20 AM
Yes it's hinged at the back and under the holder at the front is a lengthwise key that fits into a slot in the holder to locate it from wandering sideways.

The language is called "Down to earth middle english " :rolleyes:, actually Cheshire speak.


I'll have to listen again, I thought it sounded nearer your neck of the woods John?

Tim

lazlo
12-13-2009, 10:09 AM
Ah, I was wondering what happened to Bogstandard ;)

Beautiful work, but I don't really "get" the design. I understand he's trying to make a different kind of retracting threading tool, but hinging the threading bit like a shaper clapper and throwing the spindle into reverse to back-out seems like a kludge (a "bodge" for the other side of the pond).

Not trying to be critical, but he starts the other thread by looking at the marvelous George Thomas and Martin Cleeve retracting toolholders, and wanted to come up with a better design, but I don't think he succeeded, IMHO.

Carld
12-13-2009, 10:32 AM
I didn't read the thread but I did look at all the photo's and read some of his text. After some thought about it I don't like the idea of it kicking up and riding on the thread as it reverses. I would rather have it slide back and forth and that would eliminate any fear of swarf getting under the clapper as he hoped it would not happen.

With that said he did a very nice demo of the machining of the tool and is clear enough to make one on your own with your own dimensions.

I watched it last night just after John posted it and before anyone else posted to it.

DFMiller
12-13-2009, 11:03 AM
Lazlo,
Would you care to give more details on your comparison to George Thomas and Martin Cleeve retracting toolholders. They only reference I have on these was from Heminways catalog which only has a picture of one.

I know very little about single pointing but the concept presented in the video was most interesting.


Thanks
Dave

lazlo
12-13-2009, 12:12 PM
Dave, the plans are from old Model Engineer, and are reprinted in George Thomas' The Model Engineer's Workshop Manual and Martin Cleeve's Screwcutting in the Lathe.

Hemingway in the UK sells the plans and kits:

George Thomas' retracting toolholder:

http://www.hemingwaykits.com/acatalog/retractingtoolholder.jpg

Martin Cleeve's swing-away threading toolholder has a handle on a pivot that swings the threading bit up out of the cut:

http://www.hemingwaykits.com/acatalog/HK_1630_Positional.jpg

DFMiller
12-13-2009, 12:31 PM
Thanks Lazlo,
For some reason the image on the second holder did not appear on my web browser. (leopard and Firefox)
I will do some looking.
Dave

quasi
12-13-2009, 12:59 PM
there is also this one at Metal lathe accessories.

http://www.sc-c.com/metallathe/MLA16D.html

gnm109
12-13-2009, 01:06 PM
It would be particulatly advantageous for metric threads but maybe that's the idea.

Why can't everyone speak in standard English like the Americans do? :) LOL.

lazlo
12-13-2009, 01:09 PM
there is also this one at Metal lathe accessories.

http://www.sc-c.com/metallathe/MLA16D.html

I'd like to incorporate that eccentric cam into a topslide. Poor Man's Hardinge :)

Geo Thomas, of course, did the Rolls Royce version for his Myford -- an almost exact copy of the Hardinge HLV-H retracting toolpost.

Circlip
12-13-2009, 01:45 PM
The author of the lift up, (John Boggy) originally was going to do a better mousetrap in that it was going to be a retactable, based on the simpler design (Non Myford) but so that both external AND internal threads could be cut and the tool retracted which is the failing of the simpler one in that it doesn't work in the case of internal threads. This seems to have been lost in this design as although you can cut closely to the chuck, there is no retracting feature.

With a bit of careful redesign (Isn't hindsight wonderful George) the retract lever could be repositioned to the rear of the toolholder and utilising a forward and backward movement of the lever, could be made to cover both internal and external operations.

This is NOT a critisism of Boggies post, as the tool does what he intended from the modified spec. but does add a complication from just winding the offset topslide back.

Regards Ian.

dp
12-13-2009, 02:23 PM
I'd like to incorporate that eccentric cam into a topslide. Poor Man's Hardinge :)

Geo Thomas, of course, did the Rolls Royce version for his Myford -- an almost exact copy of the Hardinge HLV-H retracting toolpost.

I bought the Hemingway kit but have not worked on it yet. One thing I don't care for is that it clamps to a 4-way or QCTP and so hangs even further out to the side than if just using an HSS cutter. That might be fine for beefy lathes but when size restrictions require a smaller lathe there's just too much flex. As it is, the AXA QCTP I have puts the cutter well away from the center post and even with the gibs snugged down there's a lot of movement. A lantern type tool post would be ideal for that lathe :)

clutch
12-13-2009, 04:43 PM
Yes it's hinged at the back and under the holder at the front is a lengthwise key that fits into a slot in the holder to locate it from wandering sideways.

The language is called "Down to earth middle english " :rolleyes:, actually Cheshire speak.

I was tweeking you a bit. I had a literature class I was forced to take where the instructor had us try to comprehend some middle English. That was almost impossible. I had better luck trying to read greek.

The Madmoder link has me wondering what other sites I'm not wasting, er investing my time reading. Got any more? :cool:

Clutch

Timleech
12-13-2009, 05:32 PM
The language is called "Down to earth middle english " :rolleyes:, actually Cheshire speak.

Had another listen, he must be from the Deep South (of Cheshire), there's quite a bit of Potteries in there.

Tim

John Stevenson
12-13-2009, 06:42 PM
Had another listen, he must be from the Deep South (of Cheshire), there's quite a bit of Potteries in there.

Tim

Crewe actually old bean.
He's not from near me because there are no "Ayeup me duck" in the conversation :rolleyes:

http://www.bbc.co.uk/nottingham/content/articles/2005/01/17/features_miscellaneous_the_true_story_of_ay_up_mid duk_02_feature.shtml

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