Bridgeport Mill

Hope some one can help. What is the different in Vari-j head and j head mill. I know one is step and the other is variable but from there down they look the same also if a mill has linear scale but no monitor but does have the wiring is there anyway to tell who the mfg is oh buy the way it a 1976 Bridgeport if that will help. thank for the help?

The correct terminoloy is J and 2J. The lowers are the same on both heads, the difference is the top drive.

As for the linear scales, pictures would help. No only of the scales themselves, but the plug on the wiring. You might also look very closely at the "reader" on the scales, they might have a mfg on them. Finding a display unit for older scales can be difficult, that's what usually quit.

You can't afford to spend much money on an old DRO when you can buy new starting at $500. Now, if that mill has a more recent set of scales, that might be a different story.
JR

Scales will always have lables. Chances are though if the lables are worn off and the readouts gone the scales probaly are ready for the dustbin! Jr is dead right, fixing a old dro is putting money down the drain big time. Especialy if that entails buying a new readout unit! Now fixing a dead scales worth while. Start getting into converters bettwen old scales and a new readout and its a slippery expensive slope! Especialy if there only possibly working!

adama said:

Scales will always have lables. Chances are though if the lables are worn off and the readouts gone the scales probaly are ready for the dustbin! Jr is dead right, fixing a old dro is putting money down the drain big time. Especialy if that entails buying a new readout unit! Now fixing a dead scales worth while. Start getting into converters bettwen old scales and a new readout and its a slippery expensive slope! Especialy if there only possibly working!

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You are right about fixing old DRO's. My friend who is a professional machinist had the X scale go out on his original vintage 1980s "Bridgeport Display". We discovered that not only is there no repair support, there are no parts and there are not even any conversions that could be bought.

I sold the working head and Y scale on the Bay for him and he bought a new DRO of some brand or other.

I wouldn't even attempt to fix an old DRO. If a scale goes out and you could get a replacement that might be OK but anything more than that and you can get a new one cheaper these days.

thank you gentleman for the information will buy new if i have to.

adama said:

Scales will always have lables. Chances are though if the lables are worn off and the readouts gone the scales probaly are ready for the dustbin! Jr is dead right, fixing a old dro is putting money down the drain big time. Especialy if that entails buying a new readout unit! Now fixing a dead scales worth while. Start getting into converters bettwen old scales and a new readout and its a slippery expensive slope! Especialy if there only possibly working!

Click to expand...

Truer words have never been spoken. Invest in new DRO they're more powerful than the old ones. You don't loose your zero when you shut them off. The calculate Bolt Circle and such.