Re: [CAD_CAM_EDM_DRO] Bridgeport information request

Rab Gordon wrote:

> There's a Bridgeport coming up for auction reasonably close to me
> which is pretty rare where I stay.
> It's described as having slotting, boring and dividing heads and a
> shaping Attachment.
> I don't know what model it is but was told that the serial number is
> JB869.

Could be J8869, which would sound like a 1950s to early 1960s J head
machine. It might have a round ram, which would make it an early 50's
machine. Anyway, the 869 sounds way too early, and I haven't run
across JB serial numbers.

> I was hoping that it may be a good candidate for converting to CNC.
> Can anyone give me any more info on it or what to look out for when
> buying this type of machine.

Well, if it is a very old machine, it may have excessive wear on ways
and screws (like mine). Also, the spindle bearings are pretty expensive.
You probably won't be able to hear it run, but you can disengage the
direct drive clutch (swing handle in front on top of belt housing to right)
and then spin the spindle by hand. it should be nearly silent.
You can run the saddle back and look for wear on the frosting. If the
frosting on the ways is gone in areas, that indicates a good deal of wear.

> Also, if I do purchase it, any advice on getting it home ? What's the
> rough weight, and can they be disassembled into more manageable parts.
> Thanks in advance.

The oldest round-ram machines weighed about 1800 Lbs, a dovetail-ram
1J machine weighs about 2200 Lbs, depending on table length. If it is
a 2J (variable speed) make sure you know if it will clear the ceiling where
you plan to put it. Some machines, especially 2J's with tall motors can be
very tall, and won't fit in many basements.

I have always used a lift gate truck, and had excellent results with it.
I would take the head off the machine for moving, that lowers the center
of gravity. The head is manageable in 3 pieces. The motor comes off
VERY easily, 3 big nuts hold the belt housing to the top of the main
housing. The main housing and quill are VERY heavy, over 100 Lbs.
so be sure you are ready to handle it when you loosen the 4 nuts on
the front.

Jon