South Bend 7" shaper refurbishment

Ian

Notorious member
Doesn't look like much but many hours went into stripping the old green paint off of the sheaves, rods, linkages, and shafts. Citri-strip works pretty well for a non-tox product, just takes patience.

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Not the best light from the shop LEDs but the brass placards turned out nice after a citric acid and detergent treatment followed by Turtle Wax.

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The ram is stripped and primed (four coats, letting it harden overnight before painting tomorrow), the motor frame is cleaned, sanded, and primed, and the housing for the table advance is ready for paint and reassembly (getting the clockwork apart was a research and nail-biting hammer and punch affair which also involved making a spanner to remove the nut for the hand crank).

All that's left after finishing those items is cleaning and painting the junction box, switch box, and belt guards, then going completely through the vise, the table, all the felts and brass wiper plates, the head, and the clapper box. Lots and lots of small details to take care of there.

Repair items include fixing or re-making the damaged gib for the head, milling grinding, and scraping the bar that moves the ram, making a new crank bushing, and casting and machining a bronze sliding block if I can't find an affordable hunk of 660 or 932 bearing bronze.

This is the wear and galling that will need to be fixed on the arm. More photos to come as I go through that process. The sliding block and bushing are so wallered-out and galled from chip ingestion and lack of lubrication that there is about .030" of slop in the movement. That translates to about 1/8" of slack when the ram reverses, making a bad stop/slam/jerk at each end if the travel.

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Ian

Notorious member
This is getting out of hand! I had to learn hiw to be a mill operator and hand scraper--and repair a part-- in two hours flat.

The swing arm thingie tha makes the ram chooch was hosed, as I mentioned before, so I decided to fix it since I have to make two other parts that interface with it anyway. Here's the damage, worse here on the drive side but also very bad on the backstoke side:

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My setup on the mill, using a 7/8" HSS cutter Smokeywolf donated to my fledgling endeavors:

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After tramming the geezus out of the part on two axis (axees?) and four surfaces I got all the differences split and dove in:

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Finish pass, took .008" to clean up. Cutter had some burrs I missed but good enough for who it's for. This little machine climb-mills like a champ thanks to getting just enough tension on the y-axis gib.

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Rinsed and repeated on the other side and checked parallelism. Good as I can measure it's within a couple tenths end to end and I can't detect any vertical error besides the lines from the cutter.
 

Ian

Notorious member
The original surfaces had been scraped for flatness and oil retention, so I had to figure that out. Grabbed an old file, ground a 3" radius on it with 5⁰ negative rake, honed it, and got busy roughing in the surface. After four passes each side I got most of the milling lines out. Is it flat? I have no idea since I would have to make and scrape in a straight edge that would fit the part, and my granite surface plate hasn't arrived yet. This stuff is incredibly difficult to photograph with a cell phone.

First two passes:

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Two more passes and a light stoning to remove burrs. Did four per side.

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Different angle:

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I'm going to quit here for now, maybe try to blue the high spots with a 123 block when my surface plate gets here, make sure it's flat, and chase a few more points here and there.

This morning I called a bearing supplier Ibused to do business with in San Antonio and had them ship me a bar of 660 bearing bronze. All they had was round stock so I got a big enough piece to make the sliding block out of. I'll whittle it to size once I get the final scraping done. I don't know what the tolerance is supposed to be but I'll go for as snug as possible without binding.
 
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Bret4207

At the casting bench in the sky. RIP Bret.
I was wondering why you tore it down right off the bat. The "slam-clunk" explains it. Looks good Ian!
 
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Ian

Notorious member
I was wondering why you tore it down right off the bat. The "slam-clunk" explains it. Looks good Ian!

That's part of the reason although the worn parts I'm fixing currently come out quite easily without tearing it down very far at all. The main reason for a complete overhaul and refinish is, well, it needed every single piece cleaned, inspected, fixed as needed, and put back correctly. Half a century of abuse and neglect together with a bad "Krylon overhaul" that I suspect was a high school bodyshop student's senior project before Keith got it and the oil pump not working right for the little bit he used it meant I had to refurbish it if it was to last any time at all and have a hope of being accurate.
 

smokeywolf

Well-Known Member
Very nice cross-hatch marks on that way scraping job.
I've never scraped ways. Seen it done by my teacher when I was an apprentice. He pulled the table off a '60s Bridgeport and re-scraped the ways. He was one of the finest machinists I've ever seen. Kind of fitting since his name was Joe Gage.

This is affirmation for me, when I say old American iron is the best way to go.

Caveat: Much of the time.
 

Ian

Notorious member
Gathering more stuff. Got a 12-gauge grounded extension cord to cut up for wiring, red for the accent color. Also got some cable glands to fit the beautiful, galvanized junction box and eliminate the two rubber grommets and one Romex clamp it had. The 660 bearing bronze rod arrived, $142 to my door but I have bushing material for life.

Last night I finally managed to get the vertical adjustment crank off the leadscrew with a hook and 10# slide hammer and file the buggered machine hinge pin enough to get the clapper box apart and see why it wouldn't fully close (embedded chips, no surprise there). Once I got a good look at the ways it was obvious the thing had been crashed, badly. Sighhhhh. The gib I had seen from the first teardown, it was a compound banana (no pun intended!) with a badly smashed spot and three bumps where the ends of the gib screws had almost been shoved completely through. What I didn't expect was to find the dovetail twisted and cupped.

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So I peened and peened and dollied and straightedged and go it back straight and flat again, then measured the angle with a fishtail gauge and measured for parallel to find .012" taper. SIGHHHHH........ Then I worked the gib with vise, blocks, hammer, anvil, and stone until it was reasonably flat for 90% of its surface and checked fit. It is horrible as expected, floppy loose on one end of travel and hard jam at the other with only about 2.5" of movement. Judging by the root of the dovetails it was made this way originally, either by accident or design. The saddle? part that the clapper box bolts to is tapered the same amount but tHe opposite direction and the other machined surfaces to not seem to be bent, splayed out, or twisted so it must have been made that way but surely not on purpose. This can be corrected by gib adjustment, so no big deal, but the other part will have to be made parallel or the downfeed will never make a clean, accurate cut. The whole head of the ram has been replaced, it is numbers-matching but doesn't match the rest of the machine. Anyway, I have a lot of work to do and might end up machining the taper out of the part of the dovetail that rides on the gib after scraping in the un-damaged (opposite) side flat and true.

I forgot to photo the gib before working on it. I think it is trash and will have to be re-made. BTW, Keith, the $6M answer is gibs are always made out of the same material as the ways, almost always cast iron or extruded iron. Here are the parts I'm talking about, mounted in the rotating dovetail base on the end of the ram.

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Cool little detail here. The original, switched lamp plug on the bottom of the control box is a Hubbell Twist-Lock, and they are still in business and still making the plugs and receptacles! So I ordered one and will put in a good toggle switch to replace the missing one and have a nice lamp cord connection. Need to get after the old receptical with a camel-hair brush and Citristrip.

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Ian

Notorious member
The tool to measure the tools that need to be made to measure the tool that needs to be fixed so I can make STUFF also arrived today!

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Translation: Reference plate to make precision straightedges by hand to fit the oddball ways that must be re-scraped so the machine is accurate and true enough to make precision parts. The saddle and box table ways are also hooched. Sighhhhh......
 
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KeithB

Resident Half Fast Machinist
If someone isn't careful its possible to hit the back of the clapper box slide against the frame on the back stroke. I'm betting someone did that at least once. That probably accounts for some of the cupping and twist.

I've made numerous Aloris-type dovetail back tool holders using a relatively inexpensive dovetail cutter. Any thought about recutting the dovetail(s) and then making the gib?
 
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Ian

Notorious member
I've been scraping and filing for over two hours just on the dovetail and measuring with pin gauges and a mic and I maybe took two thousandths out of the taper. My conclusion is buy a 1.5" 60⁰ dovetail cutter and true up the whole piece, scrape it in, then scrape in the mating pieces. I need the dovetail mill to make a new gib anyway.
 

Mitty38

Well-Known Member
Ian, I appreciate your posts, like in this thread.
This is like the stuff I like to do. But a step, or two, higher on the ladder.
I am amazed at your talent , and working knowledge.
I have always considered myself a fabricator and handyman. Quite knowledgeable. But apparently not so much as my swelled head sometimes likes to think.

Please do not stop posting stuff like this, as I live vicariously thru your posts.
Sometimes I can even learn something, then reapply it, at least at my lower level.
 

Ian

Notorious member
I picked up a set of cheap sharpening stones that included a wedge slip, triangle hone, and square hone that would fit the various and sundry ways that will need deburring in between scrapings. Step two was a grand experiment in making them perfectly flat on at least one side with diamond whetstones using my surface plate as a reference, it actually worked I'm happy to say. Also trued and lapped a pair of $20 St. Gobain India whetstones and turned them into a $300 pair of precision deburring hones for a couple hours of my time. Then I got carried away and got on with checking and scraping in one of the ram ways. I really needed to hone in the bottom first but am waiting for the rubber rollers to arrive so the Prussian blue can be spread on the whoke plate evenly. I can do the side of the ram dovetail with a Bondo spatula and my finger so that's where I began.

After the first pass to get some crosshatches established:

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After four more passes on the high spots and bluing checks a spot of contact showed up in the middle of the big void, this is good news to me indicating that the way isn't as scalloped as it looks.

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Ian

Notorious member
I switched to the bottom of the ram and stones. For several reasons I wanted a ground finish (it was original and will be the reference surface by which the tower was will be scraped). It turned out to be a nightmare but after 10-12 hours of working it I got it flat and relieved a few tenths on the ends to extend the wear life.

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After the final bluing and a check in the tower which thinned the blue in the middle:

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The tower, which is arched and high in the middle be at least. 002":

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