# Bridgeport No. 1 Boring Head



## 4ssss (Dec 16, 2017)

There is a side cap screw to lock the head in place while boring. That may be your problem. Also, a stone will knock of any burrs you may have on a hardened part. The dovetail should move relatively free, but with drag, and if it moves with an allen wrench on the micrometer it is OK.


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## 4GSR (Dec 16, 2017)

The few Bridgeport boring heads I've worked with, the two pieces are a very snug fit.  Always had to gently tap the sliding piece with a soft faced hammer to get the screw started.


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## Titanium (Dec 20, 2017)

Thanks for the help.

I worked at the burrs for a little while over a couple of nights with a needle file and a stone.  It turns out that neither the base dovetail or the head dovetail are hardened.  I eventually got the dovetails to slide nicely with only a slight resistance at one end of travel (without the micrometer screw installed).  The actual operating travel with the screw installed is only 3/8”.

The side SHCS that came with the boring head is evidently not the original one because it is too short to reach across the gap from the counterbore to the threaded hole.  It appears that the SHCS locks the head by squeezing the base dovetail onto the head dovetail?

I currently have all the pieces of the boring head in a bath of Purple Power to remove the last remnants of greasy grunge. What sort of oil or grease should be used during reassembly?


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## EmilioG (Dec 20, 2017)

I would start with a light film coat of Super Lube Multi purpose grease and some Super Lube synthetic oil. There are heavier bearing grease pastes from Dow Corning and others, but they are usually black or gray. The best is the grease that Albrecht uses on their chucks but it is not easily sourced. It's a green,  PAO grease.  The Super Lube should work fine.  Mikey turned me on to it.  Dupont Chemours Krytox is very good but very expensive.


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## Titanium (Dec 25, 2017)

Merry Christmas to all.

Thanks for the recommendation of the Super Lube grease and oil.  I have been all over town and have had no luck in finding any Super Lube locally.  It is kind of frustrating because I know I have seen the distinctive green, blue, red and yellow horizontal bar design of the Super Lube package before.  Oh well, I will order some from Amazon after the holidays.

In the meantime I have removed all the parts from the Purple Power bath, rinsed everything in running water, dried, and then spritzed with WD40 to chase out any remaining water. I then used some Sta-Lube brake caliper synthetic grease, because I had some, on the sliding dovetail surfaces and the micrometer screw.  The rest of the metal surfaces was given a light coat of some turbine oil.  The movement is silky smooth now.

I still need to get the proper sized socket head cap screw to lock the dovetail.  The one I have is a 1” 10-32 and I need a 10-32 that is 1-3/4” long.

Thanks again for all the help.


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## chips&more (Dec 25, 2017)

Hi neighbor and back at you with a Merry XMAS! Not too sure about needing a special grease and or oil for the boring head? Just any good lubricant should do. Maybe select one with high pressure/friction properties? I have many Bridgeport #1 boring heads. Let me know if need to compare or something. Also have an overwhelming amount of cap screws. And then my collection of greases…Dave


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## Titanium (Dec 26, 2017)

Oh boy, you really are a neighbor.  It’s good to know there are other enthusiasts nearby.

I ended up using some Sta-Lube brake caliper synthetic grease only because that’s what I had.

How long is the 10-32 socket head cap screw on your Bridgeport No.1’s?  Also how long are the two set screws? My two set screws are two different lengths.

And now you’ve got me wondering exactly how many Bridgeport boring heads a man can have?


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