Calibrating a Rolling Mill

How do you calibrate one so that both rollers are even and your sheet
doesn't come out curved?
SilverMan
--

Real debate; No bull****.

http://groups.yahoo.com/group/Hale_Bobb/

& http://halebobb.com

Frosty wrote:
How do you calibrate one so that both rollers are even and your sheet
doesn't come out curved?
SilverMan
--

Real debate; No bull****.

http://groups.yahoo.com/group/Hale_Bobb/

& http://halebobb.com

Well be able to help you
IF
you answer the following questions
Whats the make of the mill? if known,
Is it powered or hand driven
how old do you think it is,?
Does it have a central "T" handle on its top
which has a gear that meshes with 2 gears , one on each side of the frame?
If not has it 2 threaded rods one on each side through the frame bearing
down on the top roll bearing blocks?
with holes in the top for a tommy bar?
whats the roll dia and width?

With either feeler gauges or plastigage. Remove the center gear and rotate
each end gear so that the feeler gauge has equal "drag" on both ends, then
drag the gauge across the gap to see if there are any places where it is
looser or tighter. This will help but flipping your sheet over between
passes helps too.

--

Don Thompson

There is nothing more frightening than active ignorance.
~Goethe

It is a worthy thing to fight for one's freedom;
it is another sight finer to fight for another man's.
~Mark Twain


"Frosty" wrote in message
...
How do you calibrate one so that both rollers are even and your sheet
doesn't come out curved?
SilverMan
--

Real debate; No bull****.

http://groups.yahoo.com/group/Hale_Bobb/

& http://halebobb.com

Google "calibrating a rolling mill" . Lots of interesting stuff. Try
contacting the manufacturer of your machine and ask them to send you nfo on
calibration. I take it that you are concerned about alignment along the
vertical axis rather than the horizontal. A make and model might get you
more nfo.

"Frosty" wrote in message
...
How do you calibrate one so that both rollers are even and your sheet
doesn't come out curved?
SilverMan
--

Real debate; No bull****.

http://groups.yahoo.com/group/Hale_Bobb/

& http://halebobb.com

Frosty wrote:
How do you calibrate one so that both rollers are even and your sheet
doesn't come out curved?
SilverMan
--

Trial and error.

Remove the center handle that narrows and opens the gap between the rollers.

Then lower (or raise) one of the rolls one gear tooth at a time, until your
sheet comes out even. Use cheap brass, copper or nickel silver sheet to test
this.

It is also possible that your rolls are worn to the point that this does not
work

--
Abrasha
http://www.abrasha.com

Start by setting the rollers parallel, using a feeler gauge. Then roll
some sample stock, on both ends and in the center of the rollers. You
will probably find your results vary on where you roll the stock. This
is from either the rollers not being perfect cylinders, and/or the mill
frame and fasteners stretching under the load. Then, as necessary,
adjust the rollers based on your sample pieces.. Loosen the rollers
slightly on the side away from the direction of curve, until it comes
out straight. Turning the stock over between passes helps, as well.
Don't reverse the direction of travel, however.

BTW, if you have one of the inexpensive import mills from India or
eastern Europe, it's worth your while to toss all the hold-down bolts
and replace them with high-tensile heat-treated bolts. The cheap onces
stretch noticeably. It will make a real difference in how your mill
works.