PDA

View Full Version : Lever locking tailstock



Davidhcnc
10-14-2009, 05:46 PM
This is the way my tailstock was locked before, Small chinese lathe 4" chuck. Nothing too groundbreaking.

http://homepage.ntlworld.com/david.hull35/Other%20Images/tailstock.JPG


We now have a lever locking tailstock

Parts, the square thread is 4mmx20mm. This is the bit that locks, the m10 is done both ends with loctite after adjustment.

http://homepage.ntlworld.com/david.hull35/CNC/assembly.jpg

Unlocked position of handle

http://homepage.ntlworld.com/david.hull35/CNC/loose.jpg


And locked.

http://homepage.ntlworld.com/david.hull35/CNC/tight.jpg

Operates like silk and requires no butchering of the lathe parts...I'd like to think I have invented this but most likely it has been done before!

John Stevenson
10-14-2009, 05:59 PM
can you still lock it when the tailstock is close to the saddle and the top slide is set yo zero or a small angle ?

Is there enough room for the tommy bar to swivel round.

.

Davidhcnc
10-14-2009, 06:33 PM
Well yes, that is it locked.

Because the square thread is so 'quick' it is locked by a little tweak, Plenty of room for the bits to clear.

BobWarfield
10-14-2009, 07:07 PM
That square thread is the trick, isn't it?

I made one using a cam action:

http://www.thewarfields.com/cnccookbook/img/LatheStuff/TailCamlok/P1010375.JPG

http://www.thewarfields.com/cnccookbook/img/LatheStuff/TailCamlok/P1010371.JPG

I stopped in the middle of another project to make it, so it isn't beautiful as I hurried through. Sure is a nice improvement to the lathe though. I don't miss tracking down that wrench!

Cheers,

BW

brian Rupnow
10-14-2009, 07:09 PM
That is a great idea. I have a peice of 1" acme thread rod and a follower nut that I have been saving for a project. Perhaps I will copy your idea. Thank You-----Brian

Davidhcnc
10-14-2009, 07:15 PM
yes Bob.. a little travel on the handle gives the lock without getting in the way... and I've looked at yours, and all your other stuff, many a time.

I don't mind modifying/improving my machines but always seek to do so in a way that may be put back if necessary.

brian Rupnow
10-18-2009, 06:26 PM
Your post has inspired me to make the same changes to the tailstock on my lathe. I had an old peice of 1" dia. square thread rod and follower nut that I have been saving for a project like this. It has turned out great, and I thank you for the great idea. I will attach two pictures of mine, in the full lock and full unlock positions.---Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/tailstocklockfinished001.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/tailstocklockfinished002.jpg

darryl
10-18-2009, 08:00 PM
Definitely a nice improvement. I did that to mine, and while I made do with 3/8 threads, which is the bolt size originally, it does work well and I can lock and unlock over pretty much the whole length of the bed without the lever getting in the way. At the far right, the lever has to move further to tighten, but it's still ok. I did include a way to reposition the lever handle in case of wear, etc, but I haven't needed to use that.

Black_Moons
10-18-2009, 08:29 PM
Square thread isent needed, just a low TPI (or a multiple start thread if you want really fast engage action)

Oddly enough, my insanely expensive kurt vise uses a standard V threadform for the screw.

Ken_Shea
10-18-2009, 10:08 PM
Always intrigued as how different people accomplish the same thing only in different ways here, good stuff.
I especially like using what is on hand, always thinking along those lines as well, not always successfully mind you but always thinking toward using what I have. Gives me reason not to throw things away, now, at that, I am pretty successful :D

dockrat
10-20-2009, 05:52 PM
I guess my HSM mind wasn't working when I did mine.:D No fancy machining, I just cut off the end of a 3/4 box end wrench, ground the end smooth and dropped it over the lock nut.
Here it is locked:

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1321Medium.jpg

And here it is unlocked:

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1320Medium.jpg

brian Rupnow
10-20-2009, 06:18 PM
Always intrigued as how different people accomplish the same thing only in different ways here, good stuff.
I especially like using what is on hand, always thinking along those lines as well, not always successfully mind you but always thinking toward using what I have. Gives me reason not to throw things away, now, at that, I am pretty successful :D

Ken--I agree wholeheartedly ---never throw anything away!!! I've been saving this thing since Adam was a pup. Now its my tailstock lock----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/TAILSTOCKLOCK001.jpg