Jump to content

Strange Lathe Thread


jdrichard

Recommended Posts

I have a Boley Leinen Reform Lathe that has a nut that you adjust to tighten and loosen the lathe spindle bearings. The thread on the male part of the spindle shaft are flat on the top. Like the top of the mountains have been chopped off. The mating thread on the nut also has the mountain peeks chopped off. Any guess what the reason. The TAP is a 1/2” 20 TPI SAE. And i need to make a nut that is tighter fitting.

 

 

Sent from my iPhone using Tapatalk Pro

Link to comment
Share on other sites

Also, is your plan to make a lock-nut to bind the existing nut against?

Replace an the existing nut with one that binds. Almost done: Update3f31b917a9655cba8a1fc9d2e0c6f183.jpgb2c556ff6c46f3b92effb614b0c56109.jpg323e2c54ac26e6dcf9aef3ab5bad2db3.jpg34dbc14cf344fef5409a8adb67e78695.jpgFlattening the peeks
dd455a561809a6104ff4bd3796f93719.jpg9f45b7e79411a529559c3094794ac748.jpg
Still need to shave it down a bit and then cut it on one side and compress it slightly

How springy is brass and should i heat it before i compress it a bit?


Sent from my iPhone using Tapatalk Pro
Link to comment
Share on other sites

On 16/03/2018 at 1:16 AM, jdrichard said:

2444eb5befd09e50d2077a8cdf6a9a41.jpg
This is the start of my alternate nut that i need to complete and tap and somehow cut the peeks off the mountains.


Sent from my iPhone using Tapatalk Pro

it looks like something called a butress thread

Link to comment
Share on other sites

17 hours ago, jdrichard said:


Interesting. Wide thread makes it mot durable.


Sent from my iPhone using Tapatalk Pro

    well,  the point is,  it is not a simple or a common thread.  "by any other name"  it's not easy to  duplicate without a machine shop.  vin

Link to comment
Share on other sites

On 3/16/2018 at 6:31 AM, rodabod said:

A German lathe with an American thread?

no kidding....I'd almost be willing to bet the lathe its a 12 x 1.5 thread.   Give a 12 x 1.5 tap a try.

Acme?  Buttress?  easily identified with a straight on shot of the male thread but I'll go double or nothing on the lathe bet they're not :).  If anything it would be trapezoid because its German but the pitch is way too fine, and there is no reason for it in that application.  Afaik you don't see many buttress threads outside of collets and the odd vise screw.

Why do you need the nut tighter?  Afaik its suppose have two nuts so you can lock them, i.e. staying in its spot isn't a function of the nut being tight on the shaft.  You can't really have a nut tight on a screw, there has to be clearance or it won't turn.  If its sloppy, that means too much clearance - you need a tap with a smaller pitch dia (taps are sold for the different classes of thread fit).   But i'm betting the issues the wrong thread identification.

If you did want to make it tight on the screw, you'd have to split, pry it open slightly, then thread which you can do with a tap.  Its not really a practical solution imo....when you do have to lock a nut on a thread you do so with small set screw with a brass underneath (ala Schaublin and Aciera)

End of the day I'll bet the solution is simple - a 12 x 1.5 nut that fits much better.  Make two so its a lock nut arrangement :)

 

 

Edited by measuretwice
Link to comment
Share on other sites

no kidding....I'd almost be willing to bet the lathe its a 12 x 1.5 thread.   Give a 12 x 1.5 tap a try.
Acme?  Buttress?  easily identified with a straight on shot of the male thread but I'll go double or nothing on the lathe bet they're not [emoji4].  If anything it would be trapezoid because its German but the pitch is way too fine, and there is no reason for it in that application.  Afaik you don't see many buttress threads outside of collets and the odd vise screw.
Why do you need the nut tighter?  Afaik its suppose have two nuts so you can lock them, i.e. staying in its spot isn't a function of the nut being tight on the shaft.  You can't really have a nut tight on a screw, there has to be clearance or it won't turn.  If its sloppy, that means too much clearance - you need a tap with a smaller pitch dia (taps are sold for the different classes of thread fit).   But i'm betting the issues the wrong thread identification.
If you did want to make it tight on the screw, you'd have to split, pry it open slightly, then thread which you can do with a tap.  Its not really a practical solution imo....when you do have to lock a nut on a thread you do so with small set screw with a brass underneath (ala Schaublin and Aciera)
End of the day I'll bet the solution is simple - a 12 x 1.5 nut that fits much better.  Make two so its a lock nut arrangement [emoji4]
 
 

I think i found the final solution



Sent from my iPhone using Tapatalk Pro
Link to comment
Share on other sites

no kidding....I'd almost be willing to bet the lathe its a 12 x 1.5 thread.   Give a 12 x 1.5 tap a try.
Acme?  Buttress?  easily identified with a straight on shot of the male thread but I'll go double or nothing on the lathe bet they're not [emoji4].  If anything it would be trapezoid because its German but the pitch is way too fine, and there is no reason for it in that application.  Afaik you don't see many buttress threads outside of collets and the odd vise screw.
Why do you need the nut tighter?  Afaik its suppose have two nuts so you can lock them, i.e. staying in its spot isn't a function of the nut being tight on the shaft.  You can't really have a nut tight on a screw, there has to be clearance or it won't turn.  If its sloppy, that means too much clearance - you need a tap with a smaller pitch dia (taps are sold for the different classes of thread fit).   But i'm betting the issues the wrong thread identification.
If you did want to make it tight on the screw, you'd have to split, pry it open slightly, then thread which you can do with a tap.  Its not really a practical solution imo....when you do have to lock a nut on a thread you do so with small set screw with a brass underneath (ala Schaublin and Aciera)
End of the day I'll bet the solution is simple - a 12 x 1.5 nut that fits much better.  Make two so its a lock nut arrangement [emoji4]
 
 

So i could buy a 12x1.5 nut, correct? And cut it and make it sprung. The nut hole is a 29/64 inch prior to taping.


Sent from my iPhone using Tapatalk Pro
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • people be honest.... Swatch is evil for the watchmakers and repairers, BUT not everything in watches from Switzerland is from the Swatch-Group. As far as i know, Selitta got sacked by Swatch as a Movement-Assembler for them and they started to produce Movements in their own Name with slight Modifications. As far as i know, they sell Parts to the Market for their Movements. In most cases, if a ETA-Movement fails, it is a valid Option to replace it with a Selitta Movement, which i consider the Solution for this Mess with the Swatch-Group...... I have no Connection to anybody at Selitta, but being a Swiss-Guy, i still like to have Swiss-Made Watches, but not from the Swatch-Group.   ok ? regards, Ernst
    • Just one more greedy act by Swatch. They started a number of years ago here in the US..cutting off supplies to watchmakers that could build complications that many Swatch houses couldn't even touch. Old school masters who had gone through some of the most prestigious houses in the world. Otto Frei has some statements on their page about it. I tell all my customers to avoid new Swiss watches like the plague,..unless they just want an older one in their collection that still has some parts out on the market, or they have really deep pockets and don't mind waiting months and paying through the nose to get it back. Plenty of others to choose from..IE Seiko,..or other non-swiss brands Even a number of Chinese brands are catching up with the Swiss,..and I think that in time, their actions will be their downfall
    • Yes. If that's not what you are experiencing...start looking for something rubbing. A 1st guess is that one of the hands is rubbing against the hole in the center of the dial. Especially if you now have lower amplitude in face up/ face down positions.
    • Once a movement has the dial and hands put back and it is recased, would you expect the assembled watch to have the same amplitude as when the movement is in a movement holder and is without hands and dial? Thanks
    • C07641+ not sure what the "+" is for after the last digit.
×
×
  • Create New...