PDA

View Full Version : Cathead



one123
08-19-2004, 11:55 AM
How does one use a cathead with a steady-rest to center a shaft with a
rough surface (a rough casting or hot rolled steel)? When one dials in
the cathead by adjusting the bolts on the cathead is the cathead being
supported by the bottom 2 supports of the steady rest or is the steady
rest closed and all 3 supports of the steady rest touching the
cathead? Or is the cathead hanging out in space unsupported?

Forrest Addy
08-19-2004, 12:10 PM
Look here:

http://bbs.homeshopmachinist.net//Forum1/HTML/007541.html

You adjust the cathead anyway you can. Circumstance vary widely. Usually you put the work between centers position the cathead, then dial it in using the set-screws. You have to be careful when adjusting the set screws. Over or under-torquing will force the journal out of round.

John Stevenson
08-19-2004, 02:35 PM
You have asked this exact same question on at least two other boards and got plenty of constructive answers, links and photo's.

If there is something you don't understasnd from those very clear answers why don't you ask a specific question???

Jim Hubbell
08-20-2004, 01:09 AM
A cathead and steady rest are used together to do the job you describe.
A "cathead" is the cylinder which fits over the workpiece. It is fitted with axiel adjusting screws to center it. The cathead and workpiece are then set in the steady rest. Between the 4 jaw chuck and the cathead adjusting screws the workpiece may be adjusted as desired.
I didn't mention it but the OD of the cathead is machined smooth to ride in steady rest.
Feel free to ask again if this is not clear.