I have a Bridgeport type mill from Taiwan 10X50 table size. What is the
maximum load I can put on the mill and still be within safe working
parameters? I am thinking of putting a Troike 15" cross slide rotary table
on the machine, however I do not want to break the mill, any suggestions
The Bridgeport manual for the Series 1 shows a max workpiece weight of 750#
for a 9" x 42" table. You would need to take into account the additional
overhang possible with your 50" table plus your own judgment about the
durability of the elevating mechanism.
You wanted to know the range of jobs that you can put on a knee mill.
I put a picture into the dropbox to show there are no limits to what you
can do. Here is a link:
This piece is 6' x 6' x 1' x 14' long. You can't readily see that the
main weight is being supported by an overhead crane. The forklift is
there as back up only. In this instance, the table will remain straight
so long as the overhang is always supported. Let it sag, warp the table.
One thing that is probably the most important thing to take into
consideration, is to be aware of the total weight (and how it is
supported) in regards to what the knee NUT will support. The mill in the
picture is a 1970's shop mill. One day I sat a job on the table and
stripped the nut out. Granted the nut was very worn from years of use,
still, something to be aware of when dealing with dangerous weights.
Wish I had some pictures of the 4' diam. enerpac ram that was on this
mill for a couple of days once. Had to mill a dovetail in the base. Ram
and base weighed almost 10 tons when assembled. Had it figured out the
base was somewhere around 4000#. Unit is used to form the pieces that
make up the nose of the space shuttles. First time they used it, they
tweaked the crap out of it and I got it back for build up and to redo
the dovetail slot. Those were the days. Glad I'm gone.
As for your rotab, keep it in the center of the table and you will be
ok. If you planned on keeping it on one end and the mill vise on the
other, personally, I wouldn't do so. You will wear the ways out over
time. It is good practice to keep the table clear when not set up for a job.