new lathe chuck

[skyway0018746]

hello
this might be the wrong froum but here it goes
i am looking for a chuck for my hendey lathe but its threaded and it came out to be 2"x8tpi but i cant fine a chuck or back plate and i'm not in school to make one but im trying to avoid that
does the measurements sound rite?
there is a 4jaw on it now but its a pain every time to indicate it

[Adobe Machine]

Go to the ENCO online Catalogue (use-enco.com) and search "introduction to lathe chucks") this will give you most all of the configurations of lathe chuck spindles...But,look , set up on a 4 jaw independant chuck is very good practice, and you can never beat the accuracy...Practice makes perfect, and after a time you will establish YOUR system to bring the part to be machined to zero..Most good machinest learned on a "4 Jaw".

One of the first tests for a new , prospective machinest was to set up on a 4 jaw..I figured if they could not do that accuratley, we did not need them in the shop..

Adobe (old as dirt)

[skyway0018746]

i have already looked at that enco page
have you heard of this measurement or is it odd ball?

[Adobe Machine]

No, not "odd ball", just used in machines that I have not seen in awhile..try googling "lathe chucks" you might find a good used one..doubt if any one could afford a new one..

Adobe (old as dirt)

[skyway0018746]

well since i got it up and running ive been useing it this week and realized that it only closes down to 3/4 or so, so its not that good for small work it does have a back plate (i think its called )

[Adobe Machine]

You should be able purchase a chuck that matches your back plate I.E.,a "plain back chuck" that has the same bolt circle and thread sizes as the backing plate.Be sure that you index the plate so you can return the plate to the same thread depth.

Adobe (old as dirt)

[skyway0018746]

the chuck that is on there now the bolts go all the way through and have a nut on one side but i can just replace them.
what do you mean by indexing the plate?

[Adobe Machine]

1)Tighten the backing plate on the out put shaft of the lathe. 2) Remove the chuck. 3) Using a dial indicator, indicate the surface of the plate. 4) If the plate indicates ok , then just make two punch marks, one on the shaft and one one plate so that they line up ..if you remove the plate for any reason, then you can always come back to the marks upon installation. 5)BUT if the plate does not indicate true, then get out your best carbide cutter, set the tool post height to dead center and surface the plate , start with a cut of .005, and cut the plate untill there are no more "skips". Always dress the bolt holes with a 60degree counter sink ( do by hand, only takes a few turns )so no material is sticking out . 6) mount the chuck, use a minimum of torque just to hold the chuck in place. Then chuck up a good or new 3/4 inch carbide end mill and clamp it in the chuck with smooth end out. Do not chuck up on the cutting edges, there should be enough of the stem to both chuck up and leave enough sticking out to use the dial indicator..Turn the chuck by hand , and using a rubber mallet, tap the circumferance of the chuck untill your dial indicator reads 0/0 for one full turn. Look up the torque specs for the size bolt that fastens the chuck ( should be a # 8, or an Allen head fastner,if the old bolts are not, spend the few bucks a get good ones) and using a cris- cross pattern, torque in stages of 10 lbs , still checking the dial indicator to make sure your at 0/0..even with a pilot, you will find you can move the chuck around..Takes some time, do not get mad..then you should have a good TIR..

Adobe (older than dirt)

[awright]

skyway0018746, I have the same problem. My LeBlonde 13" lathe has a 2-1/8" 5 tpi spindle nose for which I cannot find a ready-made backplate.

You can google something like "lathe chuck parts" or "used lathe chucks" and get a number of hits from used chuck and chuck parts dealers. Ask a few of them if they have a matching backplate in their junk pile. The better part of valor may, however, be to get an unfinished blank and thread it for your spindle thread. You are going to have to true up the front of the backplate and machine it to match the back of your new chuck anyway. Fortunately you have a chuck that does fit the spindle so you can machine the new backplate. Good practice.

Good luck

awright

[Kevin Taylor]

AWright I think I may have what you need how big and eor what type of chuck Kevin

[awright]

Hi, Kevin:

Thanks for the unexpected response.

I'm really looking for a 2-1/8" - 5 TPI threaded backplate 8" O.D. or larger that I can machine to match my 8" 4-jaw plain back chuck. However, a complete 3 or 4-jaw 8" or even 10" chuck with a backplate matching my spindle nose thread might be of interest also.

I'll send my email address by PM.

Thanks.

awright