Help on getting a new 4 jaw chuck

Rixtools

Rixtools

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I am pretty new and am looking for a new chuck . I have been working with a borrowed 4 jaw and like the accuracy and want my own. My lathe is an early 60's Logan 1820 . I found this 6 inch 4 jaw chuck and backing plate on Ebay . Thoughts good bad ? And of course money is a concern . This chuck and backing plate is 140 plus 28 shipping. Thanks for any input.
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I do not have experience with the chuck you show. I have experience with Shars chucks and have been happy. They have 6in 4 jaw chuck onsale for $90 with $54 backing plate, so $144 plus shipping.

Whatever chuck you purchase, make sure you check if the jaws are reversible or whether you get internal and external jaws. Also ensure you get a chuck key. Sometimes included, sometimes extra.

http://www.shars.com/products/toolholding-workholding/lathe-chucks/6-4-jaw-independent-chuck-1http://www.shars.com/products/toolholding-workholding/lathe-chucks/6-4-jaw-independent-chuck-1
 
Did you try looking for used some are in good condition. Or look for one with the back all ready mounted there out there.
 
i have 4 jaw phase 2 two keys no back plate four boltsnew apple vally mn 60 $
 
Thanks guys. I have been zapped recently on buying things and am still a little sore in the rear. Not machine tools. So I am looking for something new that is not several hundred dollars. I am just having fun and learning with my Logan not trying to do any comercial work .
 
I don't think you could go wrong with a Shars 4 jaw, I did have issues with one of the jaw sets on their 4" 3 jaw, poorly made (not ground square) and had some hassle getting them to send a replacement set. But the jaws are well hardened and the scroll is accurately fitted, not bad for 110$ incl backplate.
Mark S.
 
I bought my son a shars 4 jaw for his logan works well bill
 
Unless you do a good deal of square, rectangular or off center work buy a 3 jaw adjustable chuck, there are few things that are more tedious then having to indicate every single part that you put in a lathe.

Todays job was perfect for a 4 jaw, a rectangular steel part with a 1 1/2-12 thread in one end. This sort of thing is the only good reason to use one.
Indicate part, this takes longer then the threading.


Indicate the tool.


Set the tool height. The center of the spindle on this lathe is 8 1/6" from the ways, and no, I do not obsess over tool centering as this method has worked for me for 30 years.


Drill, bore then thread until the gauge fits, done! The set up takes longer then the work itself, if this part were round I would have had it adjusted in a 3 jaw in 10 minutes rather then 30-40. Don't use a 4 jaw unless it is the only way, as mentioned it is tedious in every way. There are eight of these parts, that is 3-4 hours of dialing in an independent chuck.
Be a machinist they said, it will be fun they said (-:

 
If you are only able to afford one chuck I would buy a 4 jaw independent style. An independent 4 jaw chuck can easily be adjusted to .000" runout. A standard 3 jaw scroll chuck usually has a runout of .001" to .003'. That may not sound like much, but it will make a big difference if you remove a part for inspection or reorient it for additional procedures. The odds of getting the piece back in the exact same orientation are slim to none.

In general a 3 jaw chuck is used when all operations can be performed with a single setup. In most cases it's wise to start with stock longer than the part you are turning. When the part is finished it should be parted from the stock remaining in the chuck to insure it is concentric to the axis of the spindle. If the chuck has .003" runout any portion of the part not turned will have the same amount of runout. Any hole bored through the piece will be concentric with the OD of the turned section, but be off center on the unturned portion.

Centering a 4 jaw chuck takes only a few minutes once you get used to it. I have 3 lathes and a dozen different chucks. All of the 3 jaw scroll chucks have .001" or more runout regardless of the manufacturer. About the only time I use them is when I'm making a part that can be done with a single setup. I always start with stock long enough the finished piece can be parted from the raw stock.

If you insist on a 3 jaw scroll chuck be sure to look at the "set true" or "adjust tru" styles. These style chucks can be adjusted to .000" runout after the part has been secured in the jaws. The downside to these style chucks is that they are about the most expensive on the market. As an example Shars sells a 6" 3 jaw adjustable style for $403.95.

http://www.shars.com/products/toolh...-0005-adjustable-universal-chuck-2-piece-jaws

The same size 3 jaw chuck without the adjustable feature runs $219.00.

http://www.shars.com/products/toolh...-cast-steel-self-centering-scroll-lathe-chuck
 
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