Some Bridgeport questions

Standard manual Bridgeports have a tilt swivel on the ram and a pitch swivel between the ram and head. "Rigid ram" machines, mostly but not exclusively BOSS NC machines, lack the pan/tilt feature, but the stiffness is improved.

You can't do a lot of horizontal milling operations this way because of the quill diameter, and the head. If you try to get the spindle low to the table and horizontal, then the motor, etc. bumps into the base. The right-angle drive and outer supports allow you to run a bare arbor right next to the table.

The M head is 6-speeds by belt, no back gear, no power feed, no R-8 taper. 1/2 Hp motor.

The 1J is usually 1 Hp, power quill feed, 4 belt steps plus an ~8:1 back gear reduction.

The 2J is at least 2 HP, otherwise same as 1J but with varispeed drive instead of step pulley.

Some are better, like Tree, some are pretty rough Chinese stuff.

Hard to say. The only thing you really can't fix is a torn-up glass scale. But, schematics are rarely available, some of the electro-optical components in the read head could be hard to replace.

Moderately useful, but can't hold a candle to CNC. I'll never go back to manual (ie, non-CNC), except on a drill press. For one-offs, though, you can live without the power feed. If you are doing heavy stock removal all day, your arms would fall off.

Jon

David Merrill

And a Wells Index

Gunner

"Liberalism is a philosophy of consolation for Western civilization as it commits suicide"

- James Burnham

Yes, thanks, that's a great website, I even printed it.

i

In a commercial environment, power on 3 axiis can be justified. Even there, most machines end up with power feed on the X travel (the long feed of the table) and strongarm on the others.

Power feed on the knee is nice if you are constantly changing from really big work to really small, but for the most part the knee feed is not a requirement. It makes a nice tool for boring deep holes, too.

One power feed is a pretty nice option for the home shop. More than that is luxury. :-)

Cheers Trevor Jones

Fella around the corner from the cabinet shop I work at has a Wells-Index , with power feeds and DRO on the spindle (IIRC) only . I don't know enough about used machines (yet) , to know if it's worth the 4k he's asking . Wired

220 3ph , and a lot more massive than a B'port . He said it weighs around 3,000 lbs ... I'm still looking for a mill , just got set back a few months by the last 'cycle crash . HF has a floor model knee mill for about 1500 , anyone have experience with this mill and/or an opinion ?

Iggy,

I would like a power feed but I am not going to buy a typical one. However, I need to save up lathe to complement my mill first.

When I get back to the mill, I am considering doing one axis cnc. I figure I can use the linux based emc

combined with a servo system to make a power feed for the X. It would seem to be a better solution since it would be programable to speed and distance and would get one well down the road to two axis control.

You with your programming, scrounging, electrical skills could to the same thing. Likely before I can get to it.

Wes

Wes, yes, if I do CNC, it would be Linux based for sure.

I could schedule some machining operation from crontab, and have my parts ready by the time the morning coffee is done. ;-)

i

Absolutely. Skip the power feed and put the money into CNC, if you will eventually go CNC anyway.