Old Bridgeport Gets New Lease On LIFE

[rb67mustang]

This video shows the head off to the side so I had lots of room to clean. I explain the Ram being stuck/seized up as well as the excessive backlash on the Y-axis screw. That's it for today.

 

[Norseman C.B.]

This video shows the head off to the side so I had lots of room to clean. I explain the Ram being stuck/seized up as well as the excessive backlash on the Y-axis screw. That's it for today.

PB Blaster is your friend fer gittin the ram loosened, up spray and tap the ram with a dead blow hammer and rock the drive handle spray let it sit fer a while repeat till it works loose ..........................BE PATIENT and persistant ....................
OH yeah pull the lock bolts out and spray the PB in them too.................

 

[rb67mustang]

PB Blaster is your friend fer gittin the ram loosened, up spray and tap the ram with a dead blow hammer and rock the drive handle spray let it sit fer a while repeat till it works loose ..........................BE PATIENT and persistant ....................
OH yeah pull the lock bolts out and spray the PB in them too.................

Thanks for your idea, Norseman, I'll give it a try and I'll let you know how it went.

 

[rb67mustang]

Next, I searched for a suitable 110v motor, drum switch, aluminum plate to mount the motor, and much needed accessories such as, 6" Vise, Collets, Drill Chuck, and the missing Draw Bar, Quill Handle & Knee crank. The Draw Bar, Quill Handle & Knee Crank are Bridgeport replacement parts and not Chinese knock-offs, because I wanted them to fit properly and last longer than I'll own the machine. Some things you just can't skimp on quality. So it looks like I don't have any photos of the drawbar, vice, and the drum switch when they arrived. I prefer a keyless drill chuck. The one I bought is a lookalike of the finely crafted German chuck I had back in my Machinist days. The collets are most likely Chinese as is the Kurt lookalike 6" vice.

 

[rb67mustang]

OK, now I'll get into the motor conversion I did so I didn't have to use a phase converter. I chose to use a flange mounted motor for ease of mounting. Most flange mounted motors also come with the standard mounting bracket which I used to my advantage as a solid place to mount the drum switch.

I don't have a good place to purchase raw material, ie, aluminum plate, or whatever I need to make the parts I need for a given project. Sometimes I buy from Ebay, or I search for the best price online in my home state, or someplace in the USA.

So, I overthought/stressed about the mounting plate thickness for a couple of days, and then I took a good look at the BP (Bridgeport) motor and its replacement. The BP motor shaft is 2 1/4" inches long vs the 1 7/8" long shaft on the replacement motor. But then it HIT ME that the BP motor housing extends 3/4" of an inch below its mounting face. Now that's a problem, and it just shortened the shaft length of the replacement motor.

OK, so I bought a 1/4" x 10" x 12' aluminum plate to mount the motor from Ebay. Then I took measurements off of the top of the BP belt housing and laid out and cut the plate, drilled the holes for the motor lock studs and the motor mounting holes, and then I cut the middle hole for the motor to fit. Notice the very dirty belt housing! I cleaned it up after I took the measurements and made a sketch for the new motor mounting plate.

Next, I had to slightly undercut the motor lock studs to account for the 1/4" inch thick plate I used. I didn't take a photo of the studs afterward but looking at the 4th image showing the studs mounted onto the plate, shows the studs are threaded at each end. One end is a 1/2-13 thread and the other end is a 3/8-24 thread. So the thin shoulder that's created between the two threads is how the studs are bolted in place on the motor mounting flange/plate.

Here's what the new mounting plate looks like in place (image 5), and we also see the much cleaner belt housing. Also, notice how the motor mounting holes are oriented. This allowed the motor mounting bracket to be positioned on the original BP drum switch side of the machine so I could mount the replacement drum switch in the same place. Anyone who's ever operated a BP will instinctively know where the fwd/rev switch is located without even looking.

If you take a close look at the piece I used to mount the drum switch, you can see a radius cut into it; it's a scrap piece from the new motor mounting plate.

The next post will reveal how I overcome the 3/4" inch loss due to the differences between the two motors.

 

[rb67mustang]

Hi Everyone,
I've been busy, but I'm going to get my thread up to date. So, I left everyone hanging on how I fixed the motor offset/shaft length issue; it's simple, I attached a hub onto the BP step pulley. How I made the hub was interesting, but I didn't take any photos of the process because I never thought I'd be sharing my BP project.

First, here's an image of the unfinished hub before attaching it to the pulley. It's slightly under 3 inches in diameter and an inch thick with a 1/2 inch hole in it. It was turned on the Harbor Freight Hobby 7" x 10" Lathe. It would've been great if I had a piece of 3" aluminum rod stock hanging around, but that wasn't the case.

 

[rb67mustang]

After the fact photos of making the pulley hub, here's the remainder of the piece of the aluminum plate I made it from. Here's the Old Granger cutoff saw I used to cut the block of aluminum to make the hub. I got the saw from my Dad before he passed away. As you can see, it doubles as a band saw for cutting small parts. This piece was about 2 1/4" x 3" x 3 1/2," the side I cut off had a saw cut face, so I cut it thick enough that it would finish up at 1 inch thick.

 

[rb67mustang]

OK, so picture this piece with a 3" circle scribed on the saw cut face and center punched to drill a 1/2" hole in it. Then I drilled the hole and I rough cut the circle in a Wood Cutting Harbor Frieght Bandsaw with a metal cutting blade in it. BTW, I also received the Band Saw from my Dad.
Then, I used a piece of 1/2-13 threaded rod that's long enough to go through the 7"x10" lathe spindle and hold the rough cut piece. To do this. there's a nut and washer on the end of the threaded rod against the end of the spindle with the threaded rod clamped in the 3 jaw chuck. Then another nut is tightened against the chuck jaws. now the rough cut disk is placed on the threaded rod and one more nut to tighten the heck out of it.

Yes, this isn't the best way to turn a blank, but the lathe can't take a big cut either. So light cuts on the O.D to clean regardless of the diameter, and face the exposed side close to the nut holding it on the threaded rod. Then remove the partially finished blank and remove the threaded rod, and change the chuck jaws to hold the O.D. of the blank. Then, I faced the blank to 1 inch thick, and I finish bored the I.D. to size.

That's how I made the pulley hub.

 

[rb67mustang]

Then I turned a pilot and polished it to 0.0005 smaller than the bore size to align the hub & pulley. Then clamp the hub onto the pulley to drill & tap & ctbre four 1/4-20 holes.

 

[rb67mustang]

OK, so the hub was finished and attached to the pulley. The question is, how did I broach/create the keyway?

So, I don't like to admit this, but I know I'm not the only guy with this problem. I either have the money and I don't have the time, or I have the time and not the money. Well, more times than not, I have plenty of time. So how did I cut the keyway? "Cut," is the word!!! Lol

I laid out the keyway at 45 degrees from the bolt circle. Then I used a Dewalt Scrollsaw to cut out the two sides of the keyway. Yes, the scroll saw is made to cut wood, but I've cut coins on it using jeweler's blades as well. Yes, the jeweler's blades have very fine teeth which should never be used to cut something 1 inch thick.

As expected, it took a very long time to make the two cuts, and I destroyed a half dozen blades doing so. Then I held the hub in a bench vise and I used a hacksaw to cut from each cut at a 45 degree angle to the depth of the two scrollsaw cuts. Then I cut the bottom of the keyway in scrollsaw.

Lastly, I hand filed a bit on each side of the keyway to fit the key.

So, this time consuming process may have saved me only 30 dollars. The time saved to find a place to have the keyway cut was worth it to me. Needless to say, I hope I never have to cut another keyway like this one. Or maybe I should say, "Don't do this at home boys & girls, we're Trained Professionals!!!!!!!!!!! LOL!
Sorry, the image is slightly out of focus, but the scribed lines are visible.