What's new
What's new

Another Bridgeport restoration

AdamC

Cast Iron
Joined
Jun 16, 2011
Location
SE PA
Inspired by Brad Jacobs beautiful restoration, I decided to follow his lead with my new bridgie. Hopefully the details I add will be useful for the next guy and not a repetition of what Brad has already done better than I can.

Picked up my new machine 2 weeks ago from a tool and die shop about 30 miles from my house. Pulled my son out of school for the day to help me. We rented a U haul trailer, just like everybody else. Because my shop is not super easy to get stuff into, we disassembled the mill in place. This was my first time taking apart a Bridgeport. I was armed with the right tools and lots of books including the original user manuals. I'm sure these will be helpful in the future, but I didn't need them to disassemble the major components. Only snag we hit was a stuck ram.

The mill is a Series I j head, built in 1967. It had what appeared to be a factory installed coolant pump in the column.
31530733540_f3012c8433_m_d.jpg


It also appears to have been originally painted green!
8AE8AC12-C64E-4101-A48B-41CF62FEEACE.jpg


Wondering what you all think of the color. Is it worth trying to restore the mill to this color? Is this the pre-OSHA/vista green? It's very light and pretty blue.

The seller inherited the tool and die shop from his grandfather. Apparently the mill I bought was in the shop when the grandfather purchased the shop many years ago. The seller noted that the mill was missing a few parts and that the y axis was not working. As I had guessed, the y axis didn't work because the $7 nut retaining screw's head broke. But I got the sense they just didn't need or want this old machine. He advertised it for $500. I didn't bother negotiate. I thought it was a steal, told the seller so, and thanked him for his generosity. In my experience, people who buy tools and sell tools are always honest, terrific, interesting people. I've bought and sold many tools over the years and have never had a bad experience buying or selling.

Disassembly took the better part of a day. My son and I unloaded the trailer the following morning.
 
Last edited:
Personally I wouldn't paint it vista green but that is probably from working in a 40 acre factory of vista green machines. I prefer battleship gray.

By all means share your restoration with us.
 
Personally I wouldn't paint it vista green but that is probably from working in a 40 acre factory of vista green machines. I prefer battleship gray.

By all means share your restoration with us.

Thanks. Yeah, I'm dragging my feet a little based on comments like yours. People really like the gray. There are a couple things that attract me to the green:

1) It has a certain 1960s cool factor. People painted things differently back then. I think we had a green refrigerator back then. (I'm three years older than this mill.) You'd never see that today.

2) I've read lots of posts suggesting Bridgeport were never painted green. This one was pretty clearly never gray. It really was green. Maybe it would be cool to see one looking as it did when it left the factory.

I'm guessing this mill is the color mine was originally.

IMG_0101.jpg

Only hesitation is I don't want it to look like like a cheap Chinese tool green.

I'll pop over to Sherwin Williams today and see what they say.
 
It also appears to have been originally painted green!
View attachment 187078


Wondering what you all think of the color. Is it worth trying to restore the mill to this color? Is this the pre-OSHA/vista green? It's very light and pretty blue.

Reminds of "hospital green". The thing about colors is that if the name is like ANSI 49 Gray, you can probably get the color years down the road. A custom color like your green might not be made anymore. But you could always try to get a color matched at the paint store. Depends on the painted part you are getting scanned.
 
IMG_2873.jpg
Is this a proper rebuild or a paint job?

Been a member here for a long time and anticipated this question. My goal with this thread is to fill in some gaps and provide a bit more detail than we've seen before, hopefully to encourage the next guy. I think there are a lot of guys just like me who buy Chinese mills because they are afraid of moving a full sized mill and the inevitable wear issue, then questions like yours. Are we foolish if we don't blueprint our mills?

Like Brad Jacobs, I guess I'm concerned that the condition of the tool needs to be evaluated and the effort and cost of blueprinting a 50 year old machine needs to be considered. Mills like this one are leaving service and are getting pushed into back rooms by pro machinists who lack the interest, skills, or business case to perform even the slightest repairs (in this case a broken nut retainer). I believe this mill is worth more in scrap metal than I paid for it. What is it capable of? I'd be happy if I could quantify 50 years of wear and encourage others to do the same.

IMG_2873.jpg

Today I stripped and degreased the column. The column ways are worn to be sure, but I sincerely doubt I could improve them. My next step will be to measure them and see what I can detect. The lower 6" had paint on them. I very gingerly removed it with straight purple power concentrate. Hard to get a picture of flaking, but I detected very little wear. Column ways are pretty uniform, but let's wait for numbers before we celebrate.
 
View attachment 187111

Been a member here for a long time and anticipated this question. My goal with this thread is to fill in some gaps and provide a bit more detail than we've seen before, hopefully to encourage the next guy. I think there are a lot of guys just like me who buy Chinese mills because they are afraid of moving a full sized mill and the inevitable wear issue, then questions like yours. Are we foolish if we don't blueprint our mills?

Like Brad Jacobs, I guess I'm concerned that the condition of the tool needs to be evaluated and the effort and cost of blueprinting a 50 year old machine needs to be considered. Mills like this one are leaving service and are getting pushed into back rooms by pro machinists who lack the interest, skills, or business case to perform even the slightest repairs (in this case a broken nut retainer). I believe this mill is worth more in scrap metal than I paid for it. What is it capable of? I'd be happy if I could quantify 50 years of wear and encourage others to do the same.

View attachment 187111

Today I stripped and degreased the column. The column ways are worn to be sure, but I sincerely doubt I could improve them. My next step will be to measure them and see what I can detect. The lower 6" had paint on them. I very gingerly removed it with straight purple power concentrate. Hard to get a picture of flaking, but I detected very little wear. Column ways are pretty uniform, but let's wait for numbers before we celebrate.

I don't think you need to scrape it in. I have owned and my manual Bport since'81 and my cnc Bport since '07. The cnc is in great shape, chrome ways, it is a V2xT that had the Boss control on it when I bought it. The iron was as new when I got it because the control never worked properly. I put a Centroid M400 control on it, no trouble at all. The old manual mill is fairly used up, It was in another guy's shop in '92-'95, they beat the crap out of it, I use it everyday, I know what it does, I make some pretty nice parts on it. About all I have done to it is replace the x axis screw and nut and grind the taper in the quill. It will get a paint job when it gets re-scraped and not before.
 
From another thread: It would be better to run it first, with minimal effort to get it working. See what it needs, etc.
Then decide what to do on the rebuild.
 
Me thinks the later. If I had the time an inclination, I'd got back and see if he's number 500.
JR
If I'm number 500, I will have failed and wasted my time and yours. (And if there are 500, I've read them all.).

Down with the flu at the moment. 3/4" dowels to check dovetails are on order. Still have to decide about paint color and get the paint ordered. I wish my surface plate was bigger. May see if I can trade for one at a local machine tool scrapper. I have an extra Schmidt vise which I think is an easy even up for a 18 x 24
 
Got to spend the last 2 days or so working on my mill. Gathered all the hardware we removed when we disassembled it for transportation. Everything got an overnight bath in the purple degreaser. I didn't buff any hardware. Just brushed out the threads using an old tooth brush. I then dumped everything in some brand-x Evaporust. I think I am not putting in the same effort Brad Jacobs did with his restores. I think he buffed every screw. And I didn't make any special dip baskets. Just tossed the parts into plastic storage bins full of chemicals. I fished them out just with my nitrile gloved hands. BTW, those nitrile gloves from harbor freight are great. And they come in different sizes which is great because one size definitely does not fit all.

After evaporust, I separated parts into those I wanted to high polish, and those I wanted to black oxide. I used Brownells Oxpho Blue.
IMG_2865_zpsa84rngq6.jpg

It's probably similar to the Caswell plating stuff Brad used. The parts come out looking a bit dry and sometimes continue to rust. So after drying I gave the hardware a bath in WD-40.

I'm not sure how many parts one 32ounce bottle will treat. I poured the whole 32 ounces undiluted into a plastic storage box. It is now rust red, tho it appears to still be working. You can see the solution in the box with the white lid in the picture.
 

Attachments

  • IMG_2865.jpg
    IMG_2865.jpg
    94.2 KB · Views: 371
Last edited:
The only thing I use WD-40 on are the hedge clippers. I will be so happy when the gallon can I have is empty.

I have been using Gibbs Brand Penetrate Lubricant for years.
5 times the price of WD but worth it.
Whenever I use any of the Black Oxide cold solutions I rinse with water, dry then oil.
 
What I wanted and couldn't find locally was LPS 3. I wanted something with a wax that would dry on the parts, possibly like Boeshield.

That said, I think WD-40 gets a bad rap. Isn't it basically a light kerosene?

Regardless, this hardware isn't "done". All of it will get re-oiled with 3 in 1. Threads will probably get antiseize, and exposed heads or tails will get waxed or something?

I use black shoe polish on my black oxide wrenches and sockets. Not exactly sure what's in it, but I'm assuming pigment, a soft wax, and something like mineral spirits. Seems to do a decent job.
 
Last edited:
If I'm number 500, I will have failed and wasted my time and yours. (And if there are 500, I've read them all.)

I've got lots of time, I'm retired. There are a bunch of hobbiests what seem to be more worried about paint color than if the mill will work. Without scraping and refitting everything, it's re-furbish, not rebuild.
JR
 
I've got lots of time, I'm retired. There are a bunch of hobbiests what seem to be more worried about paint color than if the mill will work. Without scraping and refitting everything, it's re-furbish, not rebuild.
JR

I've cleaned the column completely. The column ways are in very good condition with uniform flaking on the flat ways the entire height. I did see a small worn patch on the dovetails about 6" from the top.

A rebuild should probably address this to restore the tool to like-new condition and functionality.

My sense is that the knee is so long, the work of removing even .001" would be huge. If I don't scrape and place the knee in that wear spot, I could potentially be out of square a few hundredths of a degree. That's probably a reasonable sacrifice to make.
 
Degreasing the column removed the most recent blue paint job. I was careful to remove the purple degreaser before it attacked the base layers of paint.

IMG_2881_zpsob4audsw.jpg


This is an old tool and I expected it to be dinged up. I read about Bridgeport's famous glazing putty. But here's the thing that drives so many of us. I think this looks like crap.
IMG_2884_zpsgkdwwulc.jpg


Here is the column base immediately after shooting it with high build primer.

It doesn't just look like crap. Chips, oil, coolant and dirt all collect in these bases.

IMG_2890_zpsqw4m2oy1.jpg


So that means it's time to break out the Bondo and spot filler. I applied the bondo too thick in this picture. But I cheese grater-ed it.

After a few hours of sanding I reshot it with primer. We'll see how it turns out tomorrow.
 
Got the column mostly smoothed out and sprayed the first topcoat.

IMG_3799_zpswt5v6inq.jpg


Not sure how I feel about the color. This is the color I think the mill was originally. I'll see if it grows on me. Sometimes I find older Mitutoyo hand tools in light blues or greens. They can be very appealing - clean and fresh looking.

The previous owners' paint job left a bit to be desired. They painted over the scales!

IMG_3807_zps331smb8w.jpg


I know this isn't the scraper you've been waiting to see, but this little piece of 1095 has been really helpful. I've been using it for just about everything. Here, I'm using the corner of it to scratch the paint out of the hatch marks.
 
A pick or dental scraper would be better, in my opinion. Don't really care for the color you are using, but the finish as it looks on the column is very good. (I guess I could get used to that color over time).
 








 
Back
Top