lathe chuck mounts?

[woodtickgreg]

I have been looking at some lathe chucks and I am a little confused about all the different mounts and how they attach. Direct thread mount, plain back, d-1 etc? I was wondering if some of the fine folks here could explain how all of these different mounts attach to the chuck and to the lathe spindle. My spindle is 2 1/4 x 8tpi and I need a 4 jaw scroll chuck for my first chuck as I need to turn many pieces of square stock round. Other chucks like a 3 jaw will follow. I have been searching for an explanation of chuck mounts and I haven't found it so I turn to you all for help. I have some time to figure this all out as I am rebuilding the lathe, and searching for used chucks as well as new.

 

[kd4gij]

Well a plain back you use a back plate to attch to your lathe. The d1? is stud mount. The number after D1 is the number of studs. For your lathe you need eather a direct thread mount or a plain back and a back plate to match your spindle. For a plain back you get a back plate for your spindle mount it on the spindle and machine it to fit the chuck. That will give you the best fit.with least runnout. Hope that helps.

 

[Philco]

I had the same question, trying to figure out the different chuck mounts. I Googled lathe chuck mount types & it took me to several sites with lots of pictures & dimensions. I hope this helps.
Phil

 

[Bobby Bailey]

The number after D1 (D1-?) is not the number of studs. A D1-3 has 3 studs, but so does a D1-4. They are a different size though.
Bobby

 

[atwatterkent]

I ran into a similar problem the other day when I needed a 4-jaw chuck for my new/old 14 1/2" South Bend which takes an oddball 2 3/8-6 spindle thread. Being a rare size, I found a D1 backed 8" 4-jaw chuck, removed the backplate, bored it out and threaded it to match my spindle. This might be one other option to consider. If you find a decent chuck, another option, if your skill level dosen't include internal threading, is to purchase a backplate and machine the face to fit. This would include a light facing and machining a sholder to fit the counterbore on the chck back, turning the diameter, and drill the necessary mounting holes. Good luck,
You might have a hard time finding a 4-jaw scroll chuck. Most that I have seen, the 4 jaws are adjusted separately.

 

[woodtickgreg]

purchase a backplate and machine the face to fit. This would include a light facing and machining a sholder to fit the counterbore on the chck back, turning the diameter, and drill the necessary mounting holes. Good luck,
You might have a hard time finding a 4-jaw scroll chuck. Most that I have seen, the 4 jaws are adjusted separately.

Machining a backplate is well within my capabilities and a good option. I did find a 4 jaw scroll chuck from shars, It looks to be of good quality and the finish looks good to, specs out nice and is reasonably priced.

 

[atwatterkent]

I have purchased reasonably priced backplates in the past from "tools4less" (just one option) which carries a variety of sizes or you might find one on Ebay.
Good luck,

 

[Tony Wells]

The stud mount system is not based on either stud count, nor a bolt circle for them. Here is link that has a few dimensions for some popular chuck mounts:

http://www.victornet.com/reference/Lathe_Chuck.html

 

[rebush]

The D-1 system is a camlock. The pins have a half round cut out that the cam in the headstock uses to secure the chuck. There is a 7 degree 7 1/2 min. taper on the backer plate to positively align the chuck and headstock. The various sizes refer to the pin size and bolt circle. Roger

 

[Abom79]

D1-x camlock spindles have different sizes according to the # size, . I dont remember the stud sizes, but each one the studs are a different diameter. I want to say D1-6 uses 3/4" studs, and D1-8 uses 7/8". I may be off on the diameters but thats how the stud sizes vary. The taper fit diameters are different too.
L series spindles uses a tapered fit with keyway, with a locknut that pulls the chuck up on the spindle tight.
Direct threaded mounts are for spindles that are threaded. IF you can find the correct backing plate to fit your spindle, thread it on and machine to fit your chuck.

A few years ago, one of my customers had a blank backingplate they wanted me to machine to fit there machine. All they had was the old chuck, new chuck and new backing plate. I used the old chuck as a thread gage and machined a steel sample that fit the chuck perfect. Then a set up the new backing plate and machined it to fit my new threaded gauge. Once they were threaded to fit I then machined the face of the plate to fit the new chuck. It worked out great and they said it fit there spindle perfect.