shars lathe chucks?

Concerning Shars on line shipping costs. I went on line to order some inserts. The inserts were a total of $30.00, shipping was calculated at $40.00.
I canceled the order and emailed Shars to question the shipping costs. They advised me to order by phone, as the web site calculates shipping at a different rate than actual. I ordered by phone, total shipping was $15.00.
Just something to keep in mind.
Other than shipping I find their products are very good for Chinese.
 
Quality from Shars runs the gamut - some items great some not. I've also seen items from them be inconsistent. For example, I bought a few over-under reamer sets by accident... I meant to order 1, I ordered 11. Some sets were spot on but about 1/3 of the sets sets we're 0.001 to 0.002 oversize. The oversize sets got sent back (and likely resold by Shars), and the remaining sets were sold to fellow H-M members (I took a slight $$$ hit so fellow members could get something nice - I'm a big believer in what comes around goes around).

Another example is a 5C three jaw chuck I bought from them ran out 0.012. I was able to make it better (<0.0015) by remachining the back plate and regrinding the jaws. I've since gone to a full set of Shars collets and put the chuck on my rotary table. The collets are not bad. Hardinge they ain't, but they all seem to be within 0.0006 at 1" out. Good enough for me... When I need better, I borrow a Hardinge from work.

John
 
It is always necessary to machine the backplates ON THE LATHE you will use it on. I seldom buy chucks with built in backplates,so I always machine my own.

I AM NOT going to recommend doing this unless you are very accomplished at lathe work. You could ruin your spindle beyond repair!!!!! But,I have re ground all of the surfaces on my 16" D1-6 spindle,including the tapered hole. I always find that they are just a little out. I take just a whisker off all the surfaces with my Themac tool post grinder,one of the best out there.

I grind a very small amount off the short taper that fits into the back plates of chucks,but also HAVE TO take a bit off the face of the spindle where the chuck pegs go,so the short taper isn't too small in diameter after grinding. I apply prussian blue(high spot blue) to the surfaces,and check them for fit by mounting standard factory back plates,and checking where the blue touches. I want to see that all surfaces including the important short taper touch the backplate.

In grinding,I have found that the tapered hole in the spindle is usually a little out. This can be tricky to get the taper exactly right,so I use the factory taper adapter as a gage.

Again,I don't recommend anyone to do this as a messed up spindle would be BIG TROUBLE,and your lathe might never be the same. Most of the time,all will be well if you just machine the backplates in situ,and put a punch mark on the back plate AND the spindle to always put the back plate on again in the same orientation. You could also grind any centers you put into the tapered spindle hole,marking both to replace the center in the same orientation.

I am just a bit of an accuracy nut.
 
Some of the shars chucks come with a backplate but its removable. I highly reccomend removing it, theres only 3 shoulder screws holding it on. I found that by rotating the back plate to a different location helped me to dial in the chuck closer. I also machined some of the rear, where it threads in, off the shars back plate so that more threads catch on the spindle. It made a big difference and eliminated some flex in the chuck.
 
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