View Single Post
  #2   Report Post  
Posted to rec.crafts.metalworking
Jon Elson[_3_] Jon Elson[_3_] is offline
external usenet poster
 
Posts: 1,148
Default Deciphering a Bridgeport Mill...

On 05/11/2011 05:01 PM, Ecnerwal wrote:

I don't know enough about Bridgeports to decipher what the head is. The
lister "listed it for a friend" and says answers to my questions will be
a few days - but I can go look at it in person, so I don't think we're
looking at any Nigerian scam artists here.

http://images.craigslist.org/3m23p53...2a14c31bd3.jpg
http://images.craigslist.org/3m83o73...90f4341445.jpg
http://images.craigslist.org/3kb3o03...59755e19a6.jpg

Anything good, bad, indifferent, useful, sucky about the mills in the
pictures you can tell from the pictures would be helpful. Where to look
and what to check for (I guess I know that scraping patterns worn away
indicate bed wear, but I'm really limited on "common problems of the
Bridgeport to look out for"

Both are 2J, I think. (The one in background is a bit dim, but looks to
also be 2J.) That is the vari-speed, 2 Hp milling head. The middle pic
looks to be a standard spindle, not quick-change. Make sure it is R8 or
that you are happy with whatever spindle taper it has. Bridgeport did
have a proprietary spindle taper available, mercifully those machines
are rare.

Most motors are 230/460 V, the worst you'd have to do is swap some wires
to convert to 230. The motor plate will say.

If under power, check that the varispeed pulleys don't rattle, a common
failure is the bushing in the sheave wears out and then the pulley
wrecks the motor shaft. Check spindle bearings for nasty noises.
Check X and Y axis screws for too much looseness at the middle of the
travel.

Not that much else can go wrong with them.

Jon