SP-20 Motor (Shaft Key) and Ink Drum Removal

Hello –

I removed the ink drum chain this morning and noticed that there is quite a bit of movement in the gear that comes out of the motor. Is this normal? Or do I need to push the pin (that is sticking out) further in? Here is a video. I am sorry about the quality, but it’s in a tight space. Let me know your thoughts. Thank you.

Gear Movement

SP-20 Motor (Shaft Key) and Ink Drum Removal

4 thoughts on “SP-20 Motor (Shaft Key) and Ink Drum Removal

  • March 21, 2014 at 11:34 am
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    Removing the ink drum on an SP20 is pretty low-risk task. If it’s really dirty, then go right ahead and try it.

    There are 2 set screws, accessible from the OUTSDIE of the press that press against the shoulder screws that the ink drum arms pivot on. Loosen these and the shoulder screws should come out easily. (These 2 shoulder screws are large, slotted screws – use the biggest screwdriver you have to minimize damage on the screws.)

    The bearings in the ink drum on the SPs aren’t wood but rather resin, so they’re a little harder to damage. They also have a shoulder on them, so they shouldn’t fall into the drum.

    If you do completely dismantle the assembly to clean it, be certain that you reconnect all the pieces such that the ink drum arms and pivot points are square with each other. This is easiest achieved by dry-fitting it all back together and laying it on a flat surface (the press bed) to see that everything is square with itself. Then lock in place with the set screws. Nothing is pinned in this assembly, so this is all a straight-forward task. When I dismantled an SP25 for cleaning, I went so far as to repaint the ends of the drum. Not really necessary, or visible when assembled, but it sure is pretty.

    Reconnecting the springs is a bit fussy, but not too hard. If you have a small hooked tool, use that to pull up the top loop to connect. I’ve also used a thin rope or wire wrapped around a tool as a way to pull up on the spring. Works great.

    Go at it – it’s always good to learn how these parts of your press work.

  • March 19, 2014 at 5:32 pm
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    You certainly could remove the drum for cleaning, but if it is at all possible for you to do it while still in place, I’d recommend that you leave it in place. If the area around the shaft and frame of the press is really messed up, with dried ink and oil, it may be difficult to remove the shaft. You could try to remove the shaft, but be VERY careful when replacing the drum as the wooden bearings can find themselves inside the drum, and impossible to recover in one piece. (Voice of Experience in a former life)

    John Henry

  • March 19, 2014 at 7:45 am
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    Kyle, thank you!

    The shaft key (pin) should be pushed all the way in (toward the motor), correct? I think the shaft key is sticking out because the set screw is so loose.

    I have another question for you… Would you recommend removing the ink drum for cleaning? My press is amazingly dirty! To remove the ink drum, do I remove the ink drum arms on the right/left and detach the ink drum spring? Any other advice or tips would be greatly appreciated.

  • March 18, 2014 at 8:10 pm
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    That pin is the shaft key that keeps the gear and motor in sync. The gear shouldn’t be loose like that though.

    There’s a set-screw in collar on the gear, located directly over the key shaft. Tightening that will keep the gear from sliding and the pin from falling out. Do your best to align the gear straight with the chain and ink drum gear and tighten it down. It should be good for a while.

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