How do I remove the roller gear from a Vandercook SP20?
Hello Briar Press! I’ve been lurking for a while, and you’ve provided vast amounts of useful information, but now I have a specific question. I’m assuming the answer is obvious, but I’m using a shared press, so I’m being cautious with it.
I’ve gotten the bearers off, so one of our rollers is done, but the gear is just wedged the heck on. I’ve WD-40’d it to within an inch of its life, and taken out the set-screw. It looks like that’s all that’s holding the roller on, but I want to be absolutely sure before I go after the thing with a hammer! (Carefully, of course.) I’m attaching a picture, just for the sake of completeness.
And while I’m asking questions: should the SP-20 have Nyliners?
Thanks in advance!
Yep, it's a gear.
Are there two set screws? Check that first, then get yourself a small gear puller.
Dan
Should there be a small “half-moon” pin between the gear and core?
[thomas]
There’s only one set screw on the collar of the gear. The gear and core are connected by a woodruff key, a semi-circular disc, that works like a dove tail joint. The round end is seated in a pocket in the roller core and the flat side projects upward and is accommodated by a notch in the hole of the gear.
gear-woodruff.jpg
Once the set screw is removed, the gear should come off by using a gear puller or a machinist can use a press to push the shaft through the gear.
It is possible that the woodruff key was not replaced when the gear was placed on the roller shaft. If that is the case, the set screw may have scored the shaft or upset the metal where the key should have been. That would make it more difficult to remove by hand. Even so, the gear should come off with the extra assistance of a simple gear puller.
You might soak it well with a penetrating oil or solvent before attempting. It looks like there might be some corrosion on the shaft where it meets the gear.
John H.
While on the topic of roller gears, my challenge 15mp (similar inking system to this) has only one roller gear, and it is the roller closest to the cylinder.
Is it typical to only have one gear? Would two give me more precise inking?
The Challenge M series, Vandercook SP and Universal series all were designed to have a gear only on the back form roller. Earlier presses from both companies have a gear on both form rollers.
Thank you all so much.
I borrowed a gear-puller and that worked beautifully (even with all that corrosion) - and it turns out that the woodruff key was right where it was supposed to be. I just couldn’t tell because there was so much grime built up on the old core. (Thank you, Paul, for that excellent diagram.)
One more bearer block to get back on (the last one is sticking halfway in, and my “screwdriver” is failing) and then I get to test the new rollers!