Need a way to turn a 30 tpi screw.

All discussion about lathes including but not limited to: South Bend, Hardinge, Logan, Monarch, Clausing and other HSM lathes, including imports

Moderators: GlennW, Harold_V

John Hasler
Posts: 1852
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: Need a way to turn a 30 tpi screw.

Post by John Hasler »

I agree that there's no point in obsessing over 3-jaw runout, but I find it quite convenient that my Jacobs spindle chuck has a runout of less than .001" over most of it's range. For most purposes I can treat it like a continuously variable collet.
earlgo
Posts: 1794
Joined: Sat Jan 29, 2011 11:38 am
Location: NE Ohio

Re: Need a way to turn a 30 tpi screw.

Post by earlgo »

pete:
I did not mean to imply that the Myford Super 7 could not cut 30tpi threads some way. I meant that when I asked by friend, he said his setup with the QC box did not list 30tpi. He does not have any extra change gears.

I got the threads nearly cut on one end of the blank, but life got in the way.
(The tree service got here Friday and removed 4 trees and trimmed several more. I was sad to see the Tulip tree go as it was 21" in diameter 4' from the ground. Well over 50' tall. The arborist took it down from the top with a chain saw and climbing gear. Hard to believe that I planted it in 1975 or 6.)
--earlgo
Before you do anything, you must do something else first. - Washington's principle.
JackF
Posts: 1616
Joined: Mon Jan 26, 2009 3:56 pm
Location: Caldwell, Idaho

Re: Need a way to turn a 30 tpi screw.

Post by JackF »

Sorry to hear about the Tulip tree. Was it damaged or diseased or just getting too big?


Jack.
earlgo
Posts: 1794
Joined: Sat Jan 29, 2011 11:38 am
Location: NE Ohio

Re: Need a way to turn a 30 tpi screw.

Post by earlgo »

The Tulip had a ring around the base where the bark was no longer connected except for about 3 circumferential inches. When the tree service guy came out to quote removal of the dead trees, I asked him about the Tulip and he said it wouldn't last too many more years. It was less than 50' from the house and we live at the end of 'tornado alley' and rather than discuss this with the insurance company while the tree is in the living room, I decided to pull the plug. Penny of prevention and all that.
Thanks for asking.
--earlgo
Before you do anything, you must do something else first. - Washington's principle.
pete
Posts: 2518
Joined: Tue Feb 10, 2009 6:04 am

Re: Need a way to turn a 30 tpi screw.

Post by pete »

A drill chuck and it's runout is something I might be accused of obsessing about. Same for tool holding collets. A few posters on Youtube have shown some test results on cheap ER collet sets lately that do far worse than some of my drill chucks and 3 jaws can. Doesn't seem to be much point in buying something that has more runout and is slower to use for work holding.

I suspected as much Earl, not having the correct gearing put's an instant stop to it every time. I hope you kept some of that Tulipwood. There could be some really nice and fairly rare wood in that.
John Hasler
Posts: 1852
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: Need a way to turn a 30 tpi screw.

Post by John Hasler »

A spindle chuck isn't exactly a drill chuck. It threads onto the lathe spindle just as a regular chuck does and has a bore to match that of the lathe.
spro
Posts: 8016
Joined: Mon Feb 20, 2006 11:04 pm
Location: mid atlantic

Re: Need a way to turn a 30 tpi screw.

Post by spro »

The tulip tree itself, wasn't the problem. Trees work together. When millions of them are burned and taken down, that changes things. A communion of trees we never think about were the buffer to those which afterwards receive full force. Windy City used to be Chicago but it is everywhere now.
There is a stress upon the remaining trees. We can see damage of a way that is abnormal. The trunk is sheared and layers shifted. There is evidence that the particular tree has tried to heal this damage. Bark grows over the old wounds and tries to allow the tree to heal before the bugs get in.
The climate and wind are always going on. The remaining trees have less effect to that.
We see a split trunk or it should have been topped. That very tree has been through a million of cycles of stress and relief before it got Dead.
spro
Posts: 8016
Joined: Mon Feb 20, 2006 11:04 pm
Location: mid atlantic

Re: Need a way to turn a 30 tpi screw.

Post by spro »

Dogs are mans' best friend. Trees. Trees and lots of them, forever!
spro
Posts: 8016
Joined: Mon Feb 20, 2006 11:04 pm
Location: mid atlantic

Re: Need a way to turn a 30 tpi screw.

Post by spro »

Rejoining the actual topic; the dog for holding to center are different designs. You will note they are "off balance" with the iron ones. That also means they were turned slowly.
earlgo
Posts: 1794
Joined: Sat Jan 29, 2011 11:38 am
Location: NE Ohio

Re: Need a way to turn a 30 tpi screw.

Post by earlgo »

JackF: PM me to let me know where to send this.
Double ended 30tpi blank
Double ended 30tpi blank
--earlgo
Before you do anything, you must do something else first. - Washington's principle.
JackF
Posts: 1616
Joined: Mon Jan 26, 2009 3:56 pm
Location: Caldwell, Idaho

Re: Need a way to turn a 30 tpi screw.

Post by JackF »

Thanks Earl.

Jack Falcon
address removed by request

Where do you want me to send the money for the postage? I do have a PayPal acct.

Jack.
earlgo
Posts: 1794
Joined: Sat Jan 29, 2011 11:38 am
Location: NE Ohio

Re: Need a way to turn a 30 tpi screw.

Post by earlgo »

JackF:
It is at the UPS store today. Your Tracking no is: 1Z4X41460318860618 and it is promised at your end on Wednesday. Were I you, I'd ask the moderator to edit out your address from this public forum. You don't want to start getting political ads. :wink:

I only hope that the threads are right and you can make your part from it.

The only payment needed is to pass on the good will to another fellow who needs help, near or far. So many people have helped me over the years that it is way past my turn to help others. I am trying to correct my Karma imbalance, however futile that may be.
--earlgo
Before you do anything, you must do something else first. - Washington's principle.
Post Reply