Polishing drums on a SP-15

So I’m rehabbing my SP-15 currently. The rollers melted a long time ago, and the printer has been sitting in a garage for 20 years. There was some light rust and goop on most surfaces that I was able to remove. I followed the advice here and removed a lot of the rust with WD-40 and scotch-brite pads. Now that that’s done I feel like there are some scratches on the drums, and they seem pretty dull. Is this OK or are there any ways I can get a higher polish on everything?

 

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Polishing drums on a SP-15

5 thoughts on “Polishing drums on a SP-15

  • October 3, 2016 at 8:17 pm
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    I don’t think it is necessary to remove all scratches. Considering roller rotation, before each roller surface reaches the form, it will have passed under two distributing surfaces and most typical flaws from the drum will have been smoothed out. If you get into deeper grooves, plastic steel epoxy or Bondo are possible fixes.
    Not using the washup blade for the reasons stated seems odd reasoning to me. Its use saves a lot of effort, especially when washing for color, but it and its surrounding area MUST be kept clean (good practice for the entire press!). And you can’t trust most students to do so, so in a studio it might best be kept aside for qualified users.

  • October 3, 2016 at 7:10 pm
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    Brian – how to deal with the scratches depends on how serious the scratches are.

    My daughter has a Challenge 15MP – she dropped the cylinder on a rough surface concrete floor. (Long story about how that happened.) The cylinder was scratched and there were a couple of raised burrs, but nothing real serious.

    I used a fine metal file to smooth the burrs as much as possible, but without filing on the cylinder. I wet the file with oil. Be slow, careful and do as little of this is possible.

    Next, I wet 300 grit sandpaper with light weight oil (3 in 1 I think). Then let the press turn the cylinder while I held the wet sandpaper on the cylinder. I moved the sandpaper along the cylinder while it turned so as to not wear it down in one spot. Eventually the burrs disappeared and the cylinder felt smooth to the touch, although the scratches were still visible.

    You are not trying to make it look as pretty as new. You are trying to smooth it down so the cylinder does not damage rubber rollers. Minor scratches that are not raised up will not damage the rollers or impede getting ink on the rollers and on the type or plate – which is the purpose of the cylinder – it doesn’t ink your type. So long as its functional and does not damage the rollers, pretty is not a priority.

    If the damage to the cylinder is serious, then resurfacing may be the only choice, but i would try self-help method first.

    Good Luck

    Lad

  • October 3, 2016 at 11:35 am
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    Hi Paul,

    My press is already in the census! 27759.

    thanks for the info, Brian.

  • October 3, 2016 at 8:50 am
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    If the scratches are shallow or sending the drum, ocsillator, and rider to a machine shop is not an option, you could burnish these units by running Putz Pomade, the roller conditioner paste, through the sytem.

    To Ray’s point: aArguably, more metal can be removed on SP series presses than earlier models because the ink drum height is adjustable via set screws.

    Brian, please send me your serial number and location for the census: https://vandercookpress.info/vanderblog/census/

  • October 3, 2016 at 6:55 am
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    We bought an SP15 off eBay 8 years ago or so. The photo of it looked good, but when we got it the cleaner mechanism for the ink drum had scratched deep grooves. I suspect it had come from letting ink dry on the cleaner blade and then trying to clean the drom. This is one of the reasons why we both started using only rubber-based ink if we could and also took the cleaner blade out of the press. Our studio is located in an industrial park which has a place called J & A Grinding. I took it over to see if they could do something. They routed (milled?) the surface of the drum. Cost me $150. Honest, the drum didn’t look that good when they made it in the factory. We are getting ready to do it to our Universal III.

    Surely the main issue is to take off as little as possible.

    There was one small groove that only goes about 1″ around the drum that is still there and it isn’t very deep, but J & A said they didn’t trust going any deeper.

    Then don’t use that cleaning blade.

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