"How would you know if the headstock felt needs to be changed?"
The only way to know for sure is to have a look which involves pulling the spindle.
The good news is that they are pretty bullet proof.
With respect to spindle bearings, I like the old addage: "If it ain't broke, don't fix it!"
I generally look for signs that something is wrong before pulling a spindle. As an example: a cool running bearing has to be getting decent lubrication.
I reccommend you first flush out the bearings with Kerosene as per South Bend's instructions. Then refill with the appropriate light spindle oil (Never use motor oil.) On refilling the resevoirs, you can sort of get a feel for whether or not the wicks seem to be working. The oil cups will at first fill up, then you'll need to top off after some oil wicks up. You may need to top off a few times. If you never need to refill, the wicks may be severely plugged. If you can never get the level to stay, the wicks may be partially missing.
You can pull the entire spindle, pulley, bullgear, bearings and all on a heavy 10 to replace the wicks.
Just be sure to remove the screws for the bearing spreader before removing the bearing caps. The bearing caps have two plugs (remove with allen wrench). Beneath these plugs are the screws for the bearing spreader/ retainer. Remove these screws. Now you can pull the bearing caps and lift the spindle out.
"Also, what is a L00 spindle chuck?"
The "L" in L00 stands for long nose spindle taper. This was popular in the 50's / 60's.
The "00" is a size designator. Next comes "L0", followed by "L1", etc.
The spindle has a long tapered nose with a key sticking up. There is a threaded ring that is used to pull the chuck or faceplate, etc. onto the spindle taper and hold it there. The threaded ring will also push the chuck off the taper for removal.
The L-type spindle allowed for plug (instant) reversal of the spindle without the danger of unscrewing the chuck (a problem with threaded spindles.)
Nowadays, the D-type cam lock spindle is commonly used and noone builds L-type anymore. However, many quality machines are out there on the used market with L-type spindles.
L-type had 2 disadvantages that I am aware of. First, you lose some of your distance between centers because they stick out further. Second, because of the long taper, the acheivable thru-bore was somewhat reduced (without a honking big spindle nose.)
"What is a "wide" QC gearbox? What the positive or negative points on a "wide" QC gearbox?"
Earlier versions of the double tumbler South bend gear boxes differed from the "wide range boxes" in the range of threads it could handle and the way in which the coarse pitches were acheived.
On the earlier boxes the first row of threads (starting at 4 tpi) required a 20 tooth stud gear (on Heavy 10). The rest of the range required a 40 tooth stud gear. One would have to physically swap out these stud gears when going from one range to the other.
The wide range box allowed the same 40 tooth stud gear to cover the whole range.
Its advantages are no need to swap stud gears and a wider range of threads and feeds available.
Regards,
Dave Ficken
Meridian Machinery
http://www.mermac.com
[This message has been edited by Meridian (edited 02-21-2004).]
