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Vern Smith
08-09-2007, 06:07 PM
I would appreciate some help. I have an Enco 12" X 36" bench lathe, model #110-2079. There is a thread cut into the ID of the left end of the spindle (non chuck end). I can't get any of my gages to fit into it well. I called Enco and they say it's a thread put into the spindle for mfg. purposes.

They get regular calls about this but cannot tell me what thread it is. They do say that gun smiths use this thread for their spiders. I have no idea what a spider is but was hoping a gun smith on this forum might have one of these lathes and knows what this thread diameter and pitch might be.

The spindle bore is 38mm so I would assume the major diameter will be 40MM unless it's a complete Bas***rd.

Vern

AussieChris
08-09-2007, 07:05 PM
Vern, that's a good question. I'd like to know too.

I have a Hare & Forbes AL-330A which I'm sure is the same machine.

Chris
Brisbane Australia.

garyphansen
08-09-2007, 07:32 PM
I am guessing here, but have you tried Metric thread gauges? Gary P. Hansen

oldtiffie
08-09-2007, 07:50 PM
Deleted/edited-out

Vern Smith
08-09-2007, 09:02 PM
I tried metric as well as Whitworth gages, didn't try imperial, never thought it could possible be imperial. The guy at Enco said about half the minor diameter of the thread is removed as part of the mfg. process. Even so, some gage should line up with the remaining thread depths. His suggestion was to try threads until I find one that works. :rolleyes:

My machine was definitely built in china, not the Republic of. I can probably find other identifying markings if someone thinks that have a clone just under a different name.

Thanks for the efforts to date.

Vern

J Tiers
08-09-2007, 11:36 PM
If you can thread something onto it, you can make a "spider" which is a tube with 4 screws in it that allow holding and centering something extending thru the spindle. Like a 4 jaw, sort of, with the screws as the "jaws".

I have seen them called "catheads", and "pot chucks" also.

Much nicer if the screw threads were on the OD, although you might use them for a self-ejecting drawbar, as well.

No clue about the thread, but is is almost certainly a standard pitch, although probably a non-standard diameter.

LES A W HARRIS
08-09-2007, 11:53 PM
Vern,

Mine is a horrible fright 12 x 36.
http://i37.photobucket.com/albums/e97/CURVIC9/LATHEWORK/PANA2547.jpg

Spindle plug I made for mine, 1.625" OD.
http://i37.photobucket.com/albums/e97/CURVIC9/LATHEWORK/PANA2549.jpg


16 T.P.I.
http://i37.photobucket.com/albums/e97/CURVIC9/LATHEWORK/PANA2551.jpg

Cheers,

miker
08-10-2007, 02:19 AM
I rang Hare and Forbes and they went off to measure the thread and call me back.
They said that it is not a Metric thread and has the same TPI as 3/8" BSW (British Standard Whitworth) 55 degree pitch 16 TPI.
In otherwords, a Mongrel thread.

Rgds

Vern Smith
08-10-2007, 11:14 AM
The 16 TPI Whitworth is a pretty good match, now I have to find a 55 degree threading tool. Why would our Asian friends use a Whitworth thread? To further complicate the issue the forward/reverse switch went toes up this morning. :(

Thanks for all the help.

Vern

GRH
08-10-2007, 04:11 PM
16 TPI = 1/16" pitch
could it be 1.5mm pitch which is very close to .060"????????????

Just wondering of all the possibilities.

Remember Tiawan used to be British.

My Tiawan milldrill is a mixture of metric, whitworth and American fasteners.


Graeme

miker
08-10-2007, 08:39 PM
"Remember Tiawan used to be British."

Are you thinking of Hong Kong?

Rgds

cybor462
08-11-2007, 12:33 AM
I would appreciate some help. I have an Enco 12" X 36" bench lathe, model #110-2079. There is a thread cut into the ID of the left end of the spindle (non chuck end). I can't get any of my gages to fit into it well. I called Enco and they say it's a thread put into the spindle for mfg. purposes.

They get regular calls about this but cannot tell me what thread it is. They do say that gun smiths use this thread for their spiders. I have no idea what a spider is but was hoping a gun smith on this forum might have one of these lathes and knows what this thread diameter and pitch might be.

The spindle bore is 38mm so I would assume the major diameter will be 40MM unless it's a complete Bas***rd.

Vern

I have a Grizzly basically the same. As stated in other posts a spider works there but it will also be used for a collet lever closer. The adapter threads on it. May be for other stuff but these 2 for sure.

miker
08-11-2007, 08:55 PM
Can't wait forever for the Spider pictures!:)

This will have to do in the interim.

http://img.photobucket.com/albums/v448/mikerr/Picture20032_small.jpg

Rgds

TGTool
08-12-2007, 12:45 AM
Yours? What did you name him, Harry?

oldtiffie
08-12-2007, 05:03 AM
Deleted/edited-out

oldtiffie
08-12-2007, 07:37 AM
Deleted/edited-out

John Stevenson
08-12-2007, 08:00 AM
The thread size doesn't have to be a standard, it's not sold for any attachments to go onto , only for the factory to use.

Determining just what it is could be hard as both the pitch and OD could be non related specials.
There is not much difference between 16 tpi and 1.5 metric pitch the true conversion is 1.58.
Is the OD 39 dia, which actually IS a standard, or 40 ?
Given that the bore is 38 and some of the thread has been removed it could be 39.
The formulae is 39 - pitch for ID so 39 - 1.5 - a bit of flat could be 38.

We only have the word of the Burke and Hare guy that it is 16.

If it was me and I wanted to find out precisely I'd turn a taper on a piece of wood or nylon and screw it into the end and measure the resulting thread.

The cathead being talked about isn't quite the same as the ones show and featured in previous threads but is usualy a top hatted pot that screws into the end of the spindle and the long work is supported by 3 or 4 screws a la' the normal cathead.

My small TOS doesn't have a thread in the end, or even an extened end so the odd jobs I have to do like ball screws, I have a tapered nylon bug that's bored to the same dia as the ball screw and I whack this up the spout to stop the screw whipping.

Some really big lathes used in the oil industry have two chucks mounted one each end for the same reason.

.

oldtiffie
08-12-2007, 09:48 AM
Deleted/edited-out

John Stevenson
08-12-2007, 03:39 PM
Not quite the same Tiffie, I meant a chuck each end of the headstock, more like a permamant cat head.
See here:-

http://www.espmach.com.au/images/Megabore%2014in%20OCL%20004.jpg

.

oldtiffie
08-12-2007, 09:40 PM
Deleted/edited-out

miker
08-13-2007, 11:04 PM
Oh Tiffie, I have to get one of these....http://www.littlemachineshop.com/products/product_view.php?ProductID=2504&category=

and swap it for one of the ones in the Drill Press at college!!!

"Sir, Sir, I can't get the drill to work.." :)

Evil thoughts :)

Which book are your Cathead photos from?

Rgds

AussieChris
08-14-2007, 02:52 AM
Just back to the original question for a moment...

I checked mine out a bit closer and it's definitely a 16tpi thread. The 1.5mm pitch doesn't quite fit.

I don't know that I'd want to hang a very big chuck on it though. That part of the spindle is very thin walled.

Chris
Brisbane Australia.

oldtiffie
08-14-2007, 07:53 AM
Deleted/edited-out

Vern Smith
09-20-2007, 11:54 AM
I appreciate all the help and information provided by you fellas. Thought I would let you know what worked for me.

1.620" major diameter
16 threads per inch
cut to a minor diameter of 1.520" (compound set to 29 deg. turned in .053" sharp point on the tool)
lightly filed the major diameter down to 1.617"

This left a pretty tight fit, don't err on the big side.

Vern