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thefixer
24th May 2009, 07:49 PM
Hoping someone can help me here.How is the M30 thread cut on the spindle of a lathe? Is it turned on a machine lathe or can it be cut with a thread die? The reason I ask is because I have in my hot little hands a length of 30 mm steel rod that I would like to have threaded at one end to be able to fit my scroll chuck to.An idea I am working on at the moment. And if anyone knows how, do you also know someone that can do it for me? Preferably in the eastern or south eastern burbs of Melbourne.Mates rates would also be appreciated:D

Cheers
Shorty

DJ’s Timber
24th May 2009, 07:58 PM
For a lathe spindle I'd say with 99% certainly that it'd be cut on a CNC lathe but you can get it done with a die or on a normal lathe.

It's just a matter of finding someone who is geared up for it.

Try posting a need a 30mm x 3.5mm thread turned in the METALWORK FORUM (http://www.woodworkforums.com/forumdisplay.php?f=65)

funkychicken
24th May 2009, 08:04 PM
you can get it done with a die

You'll pay a mint for a die that big though. I can cut it on my metal lathe if you want

Enfield Guy
24th May 2009, 08:10 PM
Can be done both ways. Have a firm grip of the sales counter when you ask the price of the die at the tool shop. It also depends on the grade of steel bar you have. Harder alloys will be harder to machine either way. Have you run a file over the bar somewhere? If you can gouge the material easily with the file I would just go and buy the die. If the file skips and scratches rather than gouges then take it to a machine shop. Hold counter firmly when price is quoted.

funkychicken
24th May 2009, 08:15 PM
I can't get a 30mm die from my supplier, so there's a chance it doesn't exist. You could get a custom made one, but cutting on a lathe would be a better idea

unicorn
24th May 2009, 08:24 PM
Hi, I remember buying a lenght of threaded rod about 900 long years ago, 30X3.5 thread. If you check on bolt suppliers, you may get lucky!

thefixer
24th May 2009, 08:35 PM
For a lathe spindle I'd say with 99% certainly that it'd be cut on a CNC lathe but you can get it done with a die or on a normal lathe.

It's just a matter of finding someone who is geared up for it.

Try posting a need a 30mm x 3.5mm thread turned in the METALWORK FORUM (http://www.woodworkforums.com/forumdisplay.php?f=65)


Good call DJ. I'll give that a go.
Cheers
Shorty

thefixer
24th May 2009, 08:37 PM
Hi, I remember buying a lenght of threaded rod about 900 long years ago, 30X3.5 thread. If you check on bolt suppliers, you may get lucky!


I don't think I could ever get that lucky:(( But I'll give it a go. Thanks Unicorn

Cheers
Shorty

DJ’s Timber
24th May 2009, 08:38 PM
I can't get a 30mm die from my supplier, so there's a chance it doesn't exist. You could get a custom made one, but cutting on a lathe would be a better idea

Just cause your supplier can't supply one, it doesn't meant that you can't buy one. I've got dies up to 2" and I'm pretty certain a mate of mine has one in 30mm as well.

Grumpy John
24th May 2009, 08:39 PM
..............
Preferably in the eastern or south eastern burbs of Melbourne.Mates rates would also be appreciated:D

Cheers
Shorty

There are plenty of small machine shops in the Dandenong/South Dandenong area that would probably do it for you. Depending on what it's worth to you, you might even get it done for that universal currency, a slab :D. I would offer to do it for nix, but I no longer have access to lathes. If you get stuck PM me, I still have some contacts.

thefixer
24th May 2009, 08:39 PM
Can be done both ways. Have a firm grip of the sales counter when you ask the price of the die at the tool shop. It also depends on the grade of steel bar you have. Harder alloys will be harder to machine either way. Have you run a file over the bar somewhere? If you can gouge the material easily with the file I would just go and buy the die. If the file skips and scratches rather than gouges then take it to a machine shop. Hold counter firmly when price is quoted.

It's bright mild steel EG, shouldn't be too hard to cut. Just a matter of finding someone thats geared up to do it.

Cheers
Shorty

BobL
24th May 2009, 09:01 PM
Guys - Mcjing have 30 x 3.5 taps and dies for a whole . . . . . . . . .$18 each!!!!

I bought the tap last year and made a couple of Ally face plates for my WW lathes. I drilled the holes with an 27 mm MT2 drill I borrowed from work

The tap you can turn with a pair of adjustable spanners, but the die is 65 mm in diameter ! I have been meaning to buy a die but I want to make the die holder first.

Cheers

thefixer
24th May 2009, 09:31 PM
Guys - Mcjing have 30 x 3.5 taps and dies for a whole . . . . . . . . .$18 each!!!!

I bought the tap last year and made a couple of Ally face plates for my WW lathes. I drilled the holes with an 27 mm MT2 drill I borrowed from work

The tap you can turn with a pair of adjustable spanners, but the die is 65 mm in diameter ! I have been meaning to buy a die but I want to make the die holder first.

Cheers

Thats great information. Thanks Bobl. I'll check out the web site.

Cheers
Shorty

Skew ChiDAMN!!
24th May 2009, 09:46 PM
Just cause your supplier can't supply one, it doesn't meant that you can't buy one. I've got dies up to 2" and I'm pretty certain a mate of mine has one in 30mm as well.

Well said.

http://www.metric-tools.com/page/page/4024230.htm, for example, shows that they are available.

RETIRED
24th May 2009, 09:54 PM
M30 allthread is also available. Not sure of pitch but 3,5 is standard.

Enfield Guy
24th May 2009, 09:57 PM
Buy a bolt and cut the head off is also an option

rsser
24th May 2009, 10:00 PM
Yeah, my local industrial supplies place once sold me a 30 mm bolt. Was only about $8 which surprised them as much as me. Prob an error.

INVENTOR
24th May 2009, 10:03 PM
the fixer, if you mention what the idea is, it would be easier to give an answer. Does it need to be accurate eg: like a lathe spindle. if so you should use better steel and definitely cut on a metal lathe, with a accurate turned portion at the end of the thread for the chuck to seat on.
If its not accurate then use a die OR you can buy all of the lathe thread spindle threads 30 x 3.5, 33mm, 11/4 8TPI, etc etc as thread bar (or buy a bolt and weld it) The thread bar is available via a bolt supplier from HOBSONS or similar. People are oftne led to belive that is not available but it is, you just have to order it and often it is high tensile.

Paul39
25th May 2009, 07:28 AM
the fixer, if you mention what the idea is, it would be easier to give an answer. Does it need to be accurate eg: like a lathe spindle. if so you should use better steel and definitely cut on a metal lathe, with a accurate turned portion at the end of the thread for the chuck to seat on.
If its not accurate then use a die OR you can buy all of the lathe thread spindle threads 30 x 3.5, 33mm, 11/4 8TPI, etc etc as thread bar (or buy a bolt and weld it) The thread bar is available via a bolt supplier from HOBSONS or similar. People are oftne led to belive that is not available but it is, you just have to order it and often it is high tensile.

I agree with the above. If you thread it yourself and are using it as a rotating spindle, just a few .001 inch off and you will have wobble, wobble.

Also the chuck is not positioned by the thread, but by the spigot of the spindle and the shoulder that the chuck bears against.

Done properly on a lathe, it will run as true as the best lathe spindles.

If you are making a fixture to hold the chuck and bowl still to work on it, that is another matter. A bolt or thread bar with a nut on it for the chuck to seat on will work fine.

Skew ChiDAMN!!
25th May 2009, 03:55 PM
I had an engineer friend turn up a 2MT with threads, so I could affix my chuck to the tailstock when reverse chucking. (ie. transferring the blank to another chuck on the headstock.)

It didn't work; the chuck didn't sit squarely on the 2MT. :shrug: However, I've kept it so I can - when I get a round tuit - make an adjustable jig that I can use for carving the bowls once they come off the lathe. While still holding 'em in the chuck.

(When I start carving, precision isn't a factor. :B)

rsser
25th May 2009, 04:33 PM
Maybe if mounting the chuck and workpiece to the tailstock is the application (to centre the piece on a vac chuck eg.) it might be enough to do it in hardwood.

Turn a MT2 on one end and cut the thread by screwing the chuck insert onto the other.

Accuracy would need to be checked, as would droop with heavy lumps.