JJ Lower Pad Roller Assembly (removal for a stuck one)

[Mark Gulbrandsen]

Synco Lube and SuperLube appear to be the same product just different regional naming.

The custom keyboard community is big fans of the Krytox grease (GPL 205 especially), but probably just because they cost a lot. $$ translates to value with those folks.

https://www.krytox.com/en/-/media/fi...t-overview.pdf

https://www.krytox.com/en/-/media/fi...ose-grades.pdf

https://www.krytox.com/en/-/media/fi...06-216-226.pdf

(GPL 205 is a chemically resistant bearing grease).

No, not the same. One is spray, so lots thinner than Normal Superlub. Synco Lube is an oil made by Kano Laboratories. It comes in grease form, about like automotive wheel braring grease, spray and in an oiler. All are synthetic so they don't turn into gum.

[Ryan Gallagher]

Got her out. No parts were harmed by WD40 in the process. ;-)

I rotated the film stripper out of the way and removed the lower holdback sprocket, pushed it's shaft mostly in (to the limit of the flywheel (to avoid damage to it or the pad rollers in the fight). Then with a little more confidence nothing was going to be harmed, I was able to make the assembly shaft rotate slightly clockwise past it's "open" indent, and then visa versa counter clockwise, working it back and forth in careful increments until it had given up enough to let me pull it out normally.

Though many rags and qtips were harmed in the process of cleaning the pad roller shafts, axels, and end faces. Even the retention clip had quite a build up on it. Perhaps old graphite powder, or just grime.

Everything cleaned and restored (pad rollers in same orientation) and 2 film-spacing reset for 35mm (our next format screening). Opted to leave the shafts "dry" this time, will monitor their operation and consider if they still could benefit from a lubricant or not.

Will find out if the cleaning solved the stubborn pad roller issue after it sits for a bit. Only was sticking after being idle for a while, so will know tomorrow.

image3.jpgimage2.jpgimage0.jpg

Grime in second photo was just the first wipe of a single shaft. I have no idea when this was last serviced, but apparently a moon ago or two. Kept wiping with ISO until towels/rags were coming up clean. Same for inside axels with qtips.

[Mark Gulbrandsen]

It's too bad they pressed the two shafts into the round rotating circular piece, upper is similar, because the only thing I'd do yet is polish them up with garnet paper in a lathe. You might put it in a vise and see-saw the garnet paper around a few times, as far as I can see, that's the only way to attempt to polish them.

[Ryan Gallagher]

It's too bad they pressed the two shafts into the round rotating circular piece, upper is similar, because the only thing I'd do yet is polish them up with garnet paper in a lathe. You might put it in a vise and see-saw the garnet paper around a few times, as far as I can see, that's the only way to attempt to polish them.

I'll pick some up and give it a burl before I put any new rollers on these shafts.

Maybe something like these 3M polishing papers?... 400-8000 grit
https://www.stewmac.com/luthier-tool...ishing-papers/

[Mark Gulbrandsen]

Perhaps the green and the gray... Garnet comes in 400, 500, and 600... Most machine shop supply places stock actual garnet paper, even a full stocking Ace Hardware usually has it.

[Ryan Gallagher]

Perhaps the green and the gray... Garnet comes in 400, 500, and 600... Most machine shop supply places stock actual garnet paper, even a full stocking Ace Hardware usually has it.

I mean garnet paper is just sand paper isn't it? and 600 grit is pretty course for polishing metal. Usually you have to proceed all the way to buffing compounds to get anywhere.

EDIT: Okay the differences are the abrasive material. Garnet for all things including metal. Emory (Corundum) for metal. "Sand" for wood and plastic.

I had some electricians emory cloth already, but only one grit, definitely too course for polishing steel.

[Mark Gulbrandsen]

The 600 garnet will give a pretty good polish by itself. But you can only polish so much. If you over do it, the roller OD and shaft size end up with too much clearance. Sometimes galling is so bad, the shafts have to be replaced. For those, if Brad doesn't have new shafts, then you have to visit a grinding shop.

[Ryan Gallagher]

Happy to report my stubborn pad roller was happy today, moving easily as it should with no nudging required to break some initial friction from whatever was in there.