Lathe Toolpost Stud Thread

[electrosteam]

My Harrison M250 came without a QCTP, but with a fixed stud.
The stud is M10 into the topslide, 1/2 " body and M12 at the top for the retention nut.
I need to make a new longer stud to enable me to fit an Algra QCTP currently used elsewhere with a 1/2 " stud and 1/2" W nut.

The 1/2" W nut works so well that I am inclined to repeat this for the new stud.
It appears that generally a coarse thread is preferred for the retention nut on lathe toolposts.
But, I have had a couple of conversations with local industrial component suppliers indication that W is no longer in demand and that UNC is the preferred usage.

Any comments on what to use, M12, 1/2" W or 1/2" UNC ?

John.

[morrisman]

My Harrison M250 came without a QCTP, but with a fixed stud.
The stud is M10 into the topslide, 1/2 " body and M12 at the top for the retention nut.
I need to make a new longer stud to enable me to fit an Algra QCTP currently used elsewhere with a 1/2 " stud and 1/2" W nut.

The 1/2" W nut works so well that I am inclined to repeat this for the new stud.
It appears that generally a coarse thread is preferred for the retention nut on lathe toolposts.
But, I have had a couple of conversations with local industrial component suppliers indication that W is no longer in demand and that UNC is the preferred usage.

Any comments on what to use, M12, 1/2" W or 1/2" UNC ?

John.

Hi John

1/2 " W is a odd size thread as it is 12 TPI . I ran into problems finding suitable bolts in that size as my T&C grinder has that size thread . I ended up making some suitable bolts on the lathe .......... Mike

[pipeclay]

If the current nut is working per design stay with what you have,no need to reinvent the wheel.

Is the complete tool post in your possession or only the block,if only the block then make the stud what ever you want and either make or buy a nut to suit.

The only down side of retaining the 1/2"BSW or 1/2"UNC will be if other spanners required for the lathe are Metric,you will have to use an Imperial spanner.

[electrosteam]

Mike,
I would have thought 1/2" W (12 tpi) was one of the most common bolt sizes on the planet when the British Empire was in full force.

Pipeclay,
The 1/2" W nut has a mating spanner made from a 20 mm hex socket permanently attached (epoxy) to a suitable handle.
The nut was machined down to fit the socket.
The spanner works great, but if I had my 'druthers', it would be a little lighter as it is normally stored in a rack above the splash apron, not left on the QCTP.

As I already have the nut, the 1214 bar currently being formed into the stud will be 1/2" W.
But, can anyone confirm the drop in interest for Whitworth threads ?
I despair that Bunnings, and others, continue to display Whitworth fixings enticing the punters to use these for general work.

John

[Steamwhisperer]

No interest drop here John.
Not even an interest drop in British Standard Whitworth.
I'll start my apologies now guys.

Phil ( with a smiley inserted)

[pipeclay]

Any particular reason for not using high tensile for your stud?

In regards to the BSW threads being displayed in hardware stores why not,most people that would go to a general hardware to buy fixings would really care what they got as long as it does the job they want it for.

I dont really think the majority of people using a general hardware store would even know that there are differences in thread types apart from a fine or coarse thread.

I would think that the majority of people seeking a specific type of faster for engineering purposes would be sourcing their requirements from an Industrial fastener supplier.

[electrosteam]

The 1214 was what I had, never really considered going to a higher material rating.
I have never tried to screwcut high tensile, would I need a carbide full form tool ?
The two previous studs I have made to date were 1214 and cut with HSS, but they have not been used all that much, so any deterioration (stretch) with multiple On/Off cycles is unknown.

As an aside, Edcon Steel in Marayong (Sydney west) appear to be increasing their stock of small off-cuts and seem pleased to see hobby machinists.

John.

[bob ward]

Mike,

But, can anyone confirm the drop in interest for Whitworth threads ?
I despair that Bunnings, and others, continue to display Whitworth fixings enticing the punters to use these for general work.
John

Whitworth was from the 1850s THE nut and bolt standard in the UK and colonies. It was dropped as a standard in Australia in the mid 1960s or early 1970s when we became a metric country.

Bunnings et al keep selling their cheese steel whitworth bolts because they keep selling. Good grade whitworth bolts, especially in the larger sizes are getting harder to find and more expensive.

For myself, all my new work is done with metric fasteners. Old UK and Australian stuff I use BSW BSF, old American stuff I use UNC UNF.

[Techo1]

[QUOTE=bob ward;
For myself, all my new work is done with metric fasteners. Old UK and Australian stuff I use BSW BSF, old American stuff I use UNC UNF.[/QUOTE]

Try and buy a BSF bolt or screw these days, almost impossible. I can get box quantities or pay through the nose for postage on small quantities which is what I have to do at the moment.

[pipeclay]

John you would be able to cut the stud with HSS.

[Michael G]

Try and buy a BSF bolt or screw these days, almost impossible.

Try these guys
Classic Fasteners
I haven't used them but a friend of mine who does old motorcycles does.

Michael

[Techo1]

Try these guys
Classic Fasteners
I haven't used them but a friend of mine who does old motorcycles does.

Michael

Yes they are the guys I was referring to Michael, a bit expensive both for the bolts and for postage in my opinion.

Lex.

[Oldneweng]

My Nuttall lathe uses Whit bolts. I replaced the tool post bolts with 1/2 inch W caps bolts. Had no problem buying them. Not from bunnies tho! They were 7/16 inch W but the threads were somewhat damaged and a few had already been tapped out to 1/2 inch so I did the rest. I have never had any problems buying Whit bolts/nuts but I can only get HT by asking for them. They are not on display at our normal bolt suppliers, but out the back so I have not seen what is actually available.

I tend to use metric more than imperial for general work these days. I know they are going to be available into the future. Mostly 12mm but then I have hundreds of 12mm bolts/nuts/washers salvaged from an expansion job at work. Funny how the contracters rip down a lot of the existing stuff and replace it with new when expanding. This case was adding another 20 odd overhead fermenters in line with the 20 odd that were installed 2 years before. I also have masses of 16mm and 20mm bolts/nuts/washers. I am sure I will find a use for the 20mm one day.

As to comments about what to use, I personally would avoid using imperial threads on a metric lathe. It just complicates the issue and someone at some point is going to get confused by the difference.

Dean

[nadroj]

I despair that Bunnings, and others, continue to display Whitworth fixings enticing the punters to use these for general work.

John

I'll despair if they stop.

Jordan

[azzrock]

g,day has any one mentioned that bsw is the better thread.
its just not quite as easy to make.
it didnt go out of style or fashion.
the US just used there lend lease leverage to get there style
the 60 pointy form when they had the upper hand during ww2.
that is i think that's what happened.
aaron