Questions on new chuck.

[littlejack]

Hey guys:
I am going to buy a new chuck for my Atlas QC54 lathe. Looking at the Shars, part no. 202-5404.
It was stated over on one of "iron mans" threads, that this would be one of the better upgrades on these lathes. Apparently, the original
chucks leave a lot to be desired. With all of that being said, I have a couple of questions.
Is the two piece "reveresable" jaws, as good as the two set of jaws option? In other words, is one type better than the other?
Secondly, Maybe this is a no brainer.
Would it be better to buy a chuck with a backing plate that needs the "shoulder" turned to fit into the
back of the chuck? This would make for less TIR on the particular lathe, provided the turning to fit was done on the lathe that
the chuck was to go on?
Regards
Jack

 

[iron man]

I have always used the removable reversible jaws and really found them to convenient I really could not answer which is better I would think it would be a toss up. As for the pre-threaded one or one with a back plate I have found with either you MAY have to re-grind the jaws a bit just to true it up with your lathe spindle usually not very much. Ray

 

[littlejack]

Well hell iron man, looks like it is unanimous. LOL
Thank you for your reply. I will be ordering me a new chuck.
Regards
Jack

 

[DamicoTileCo]

How timely this thread is. I am also looking to buy a new chuck for my 12x24.
I would like to find one that just threads right onto the spindle but don't know where to look for one.
I would like a 3 jaw scroll and a collet chuck to fit my 1 1/2 x 8 tpi spindle.
Will I have to use a adapter plate?

 

[iron man]

Shars, Grizzly there are a few sites that have what you need you can get one either way the thread you have is very common. Ray

 

[rgray]

Is the two piece "reveresable" jaws, as good as the two set of jaws option? In other words, is one type better than the other?

Regards
Jack

I like the bolt on two piece jaws. I always figured I would get a set of soft jaws...then when I really got serious about getting some all I found was jaws from 1018 steel..So I ended up making my own from 7050 aluminum. They really aren't hard to make on a mill.

In the picture the two on the right hold 1 3/4" diameter one way and 4" when turned around(course there are three of them just two pictured).
The three blanks on the left show top and bottom before machining to fit anything specific and a side view they are 2 1/4" tall.
These jaws would run into one another when installed and tightened down. That preloads them for machining to the size wanted. Then just cut or file a small amount from their corners so they no longer run into each other when gripping the diameter selected.

That only works if you want a bottom for the stock. If you wanted stock to go clear through the jaws a different preloading arraingment would have to be made.

Don't forget to number them and cut a little relief in the bottom so your stock will sit flat on the bottom(get rid of radius from cutter).

 

[iron man]

Nice work I like the removable jaw's as well if you can afford them they are a little spendy but nice. Ray

 

[chips&more]

I think the chuck is the heart of your lathe. Get the best chuck you can afford. I would make it a “must have” to have the adjustable centering feature. Two piece jaws are good. They stand a little more proud, so that holds your work a tad farther out from that front headstock bearing. But, they also give you the option to attach soft jaws easy enough. And a chuck with an add on back plate also extends everything out more from that front bearing support….Good Luck.

 

[littlejack]

Thank you all for your replies. I have decided on one of the reversible jaw type chucks.
Just one problem.
I just won a steady rest for my machine on flea-bay. Now I have to build up my machine tool fund back up.
I have been wanting one, so now that is out of the way. Hopefully I will get a new chuck in the next few weeks.
Regards
Jack