Sigh. I didn’t want to do it. Really. Just a light cleaning and use it.
It didn’t look too bad (this is the sellers picture). But the crust was thicker than I can tolerate and in places I couldn’t access (under the frog, between the plates). So it needed to come apart. And so it began.
Turns out, it is not meant to come apart. But, I did not realize this. There are three pivot points (one to tilt the frog, one for the lever cap that clamps the blade and one for the tilt rod) that all look like through pins. The one in the push rod is but it declined to move. I had a sneaking suspicion that the others might not be. At any rate, they didn’t want to move so I modified a hacksaw blade to fit in the gaps and cut the pivot pins.
With everything apart, hit it with a wire wheel then into a vinegar bath for several days.
To remove the cut pins, I drilled them and then drove out the “open” ones (with a pin punch), except the ones in the body which absolutely did not want to move. To remove the blind pins, I drove in sheet metal metal screws, which was usually enough to get the pins to turn and twist out. Others, I used a crowbar to lever them out (via the screw).
The pins in the body were a challenge and after I got them out, I found out why – the ends of the pins are serrated to cut into the cast iron sides (you can see this if you click the photo to make it bigger). I wound up mounting the body on the mill to (very carefully) remove most of the pin and was then able to peel them out with a punch.
• The white stuff: The frog plate didn’t seem very flat so I took a ruler to it, jeez it was horrible. The bottom left corner was really bad because it left the scraper unsupported for quite some distance and it is over the pin hole so I was reluctant to get rid of too much metal. I bought some of that epoxy putty stuff you cut, kneed and press in place (no bondo close by). So far so good but I’m keeping my fingers crossed.
• For the big pins, I drilled and tapped (#10×24) some stainless steel rod and pressed it into the pin holes. Stainless cap screws (w/heads turned smooth) thread into them and washers center the frog. The body was drilled so the cap screw rides in the bore, it also makes assembly possible as the screws have to be inserted from the outside.
• I had more room for the lever cap pivots so I made reverse shoulder screws (these will be replaced with stainless). Due to size constraints, I used metric 5mmx0.8; the root diameter is just a bit bigger than the pin hole. The pin hole diameter is constant, so I could tap the outer hole, remove the screw threads so it would fit the inner hole, basically as minimal modification as possible while making future disassembly possible.
Since I’m going to all this work, why not over do it?
• The brass knobs looked like someone had used pliers on them and the knurling was toast so I redid them with a chevron pattern. Bye bye patina.
• The push rod pivot end was too narrow (for me) and sloppy in the frog so I made a new one out of stainless. If you look closely at the threads, they have a really strange form. Not sure how I did that but it works fine. Even stranger, it is a standard NC thread (5/16″ x 18).
The cap screw is 5/16 x 20 and the handle screws are 1/4 (or 9/32, not sure which) x 18. Both screws are “Stanley standard” you won’t find at the hardware store. Which makes every thread (3) different.