Golding Pearl (NS) - gear backlash
I am in the process of restoring a Golding Pearl 7x11 NS. There is some play in the main gear set.
When rotating the pinion gear shaft, while holding the bull gear immobile, I measure 3/16” at the tip of the pinion gear teeth.
How much backlash is considered “normal”?
Other than a) replacing the gear(s) and b) heavier grease, is there any adjustment mechanism or recommended course of action.
I’ve seen this on a C&P as well, although the slop in gear play is considerably less than 3/16. In my case my main concern was the amount of time the press had spent in the weather (It was in a weed-filled yard.)
I’m guessing you’ve check to see the condition of the bearing face that the shaft rotates in. That it’s not out of round or worn so the gear is lower within the frame that it would have been “out of the box.”
The slop or backlash in my case causes the press to rumble as it turns at speed but otherwise it runs well & prints well. Lucky I didn’t need to get the metal machined & a new bearing face pressed in. Probably at that point it would have been better to get another press. One of the joys of “restoration.”
Good luck.
Nils
http://thetagalongpress.blogspot.com/
I had a similar problem on my C&P and it turned out that the key holding the pinion gear on the shaft was moving slightly in it’s slot. I put in a shim and it’s been fine since. Of course, there’s always a small amount of play, especially in an older machine.
Make sure that the gears are tight on their shafts. Also, check and make sure the play is not at the opposite end of the shaft from the gears or somewhere farther back in the mechanism. I’m not really familair with the gear train on a Pearl but mechanically speaking any of those issues or any combination of them could cause play and might make it appear that the gears are excessively worn when in fact they are not.
Like Nils wrote, in practice a little play may not matter. But with a heavy impression the play can allow the back pressure from the impression to move the gear train backwards the distance of the amount of play. This will at the least cause a “clunk” at each impression but, at least in my limited experience, that’s also a sign of too much impression anyway.
Rich