On Thu, 09 Oct 2003 20:09:33 GMT, "tony"
wrote:

===greets all..
===having some trouble using/diagnosing the powerfeed
===on a Jhead bridgeport.
===
===i can get it to engage in both directions... "Up" has
===alot of power, i can't stop the quill by pulling on it.
===however, downfeed seems to kick out with little
===resistance.
===
===ie, using it to drill holes.. it'll feed down, but
===as soon as the bit touches the workpiece, out goes
===the powerfeed.
===
===anythoughts? is this thing broken? or am i not
===engaging it correctly?
===
===any help appreciated.
===-tony
===
It sounds like the trip lever is out of adjustment. There is a small
setscrew used to adjust the quill trip pressure, located on the
bottom of the quill. It does not take much of a turn to make a lot of
difference. These are part numbers J-42 (trip lever) and the
adjustment screw is #J-279

Some other items that can cause this exact problem is:
The pivot pins on the linkage that is on the lever on the left side of
the machine (cover has 2 screws and has a bronze or brass linkage rod
extending out of it) can come out, and not provide sufficient throw to
lock quill in power feed.

Another cuplrit is the trip plunger. Its a small dumb bell shaped
item with two balls about 5/16" in diam on a shaft of about 1/8 "
inches in diameter, made in one piece. Looks like - O-O-
If the piece between the ball gets broken it does not sense the
pressure properly. The item costs about $5.00. Its item number J-39 on
the parts listing. If its broke, it can be a real chore to remove the
broken piece.

Another thing to check is that the quill stop collar item J-36 is
securely tightened to the quill. I would clean and relube all the
items associated with the powerfeed assembly, and inspect and adjust
the downfeed pressure.

A little play here and a little play there all adds up, and a little
crud or stickyness also makes for a a powerfeed that don';t work
right.

If you need an IPB on that mill its available on my site.

Regards


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