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Thread: Water seal for jobo 3010

  1. #11
    Vaughn's Avatar
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    Re: Water seal for jobo 3010

    Excellent...let us know if the fix fails over time, as only time will tell. There is a maximum temp recommended for cleaning the drums -- don't know if there is one for your repair material.
    "Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China

  2. #12
    Resident Heretic Bruce Watson's Avatar
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    Re: Water seal for jobo 3010

    Quote Originally Posted by Songyun View Post
    Update, I bought some silicon based water seal from amazon, and applied to the crack, it works. The crack is small. I will just develop 8-9 sheets instead of 10 sheets each run, which is not a big deal, I uses fuji quick change holder, so 8 sheets works for me.
    If the crack continues to propagate (it probably will), you can probably stop if from growing by drilling a small hole (small as in a millimeter in diameter or so; bigger won't make it work better but won't exactly make it worse either) right at the end of the crack. So that the crack doesn't end in a sharp point (technically, a "stress riser") but instead ends in your newly drilled round hole (technically a "stress relief"). Center the drill bit on the tip end of the crack, so that you get clean un-cracked material for like 355 degrees. After gently drilling said small hole, fill it just like you already did for the existing crack. Done correctly there's a good chance you will stop the crack in its tracks. Else, you should at least stop it from growing for a good long time.

    And y'all thought a mechanical engineering degree was a waste of time.

    Bruce Watson

  3. #13
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    Re: Water seal for jobo 3010

    Quote Originally Posted by Bruce Watson View Post
    ...And y'all thought a mechanical engineering degree was a waste of time.
    Drilling into a wall of a narrow cylinder will be an interesting challenge -- must be a 90 degree attachment for a small drill out there.
    "Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China

  4. #14

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    Re: Water seal for jobo 3010

    The tanks are ABS, so as mentioned something made for a Styrenic model kit could solvent weld the crack if you could get to it. Sounds like what you have is working. Once you have Silicone on the part, I wouldn't try a solvent weld without cleaning it up throughly.
    3M Super 33 electrical tape on a clean surface might be a quick patch as well. Call Catlabs.

  5. #15
    Resident Heretic Bruce Watson's Avatar
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    Re: Water seal for jobo 3010

    Quote Originally Posted by Vaughn View Post
    Drilling into a wall of a narrow cylinder will be an interesting challenge -- must be a 90 degree attachment for a small drill out there.
    It's not as hard as you might think -- the drill bit is hard, the plastic isn't, the bit is small in diameter, and there's no serious need of accuracy. A few degrees off plumb won't matter much. And you've already got a "pilot hole", also known as the end of the existing crack that you're trying to "erase".

    You can always get some PVC "plumbing pipe" in about the right diameter to practice on if you want. And yes, there are some tools to help you make a 90 degree hole in the wall of a round pipe is you want to find them and use them.

    Bruce Watson

  6. #16

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    Re: Water seal for jobo 3010

    The "cylinders" are not round. They are two injection molded halves that are solvent welded together by Jobo. Do you have a "crack" very unlikely unless the cylinder was struck with considerable force. Or is it a "seam" that's come apart. I wouldn't go drilling anything if you are getting by.

    ABS is indeed notch sensitive. Relieving the stress crack, with a nice round hole is a good way to stop the progression of the crack. I would consider that as a last ditch effort.

    The chemistry you use can have an effect. When we were testing ABS and HIPS for environmental stress crack resistance, we would spray the parts with a mixture of Oleic acid and Cottonseed oil, the baked at 140°F. If there was molded in stress, or the plastic wasn't right cracks would develop in the parts. For final approval we would thermal cycle 8 hours minus 30°F, followed by 8 hours ambient, followed by 8 hrs 140°F. The part needed to pass 5 cycles minimum.
    When you get into 3rd party agency approvals like UL, CSA, and EU it gets a lot more complicated.

    Jobo had to change the water bath level in the CPP3, apparently to comply with newer electric safety regulations. It also saves you from flooding the controls of the lovely machine.
    Best Mike

  7. #17
    Vaughn's Avatar
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    Re: Water seal for jobo 3010

    Quote Originally Posted by Bruce Watson View Post
    It's not as hard as you might think...
    I am thinking of how it is to drill a hole in the sidewall of a 2"(?) diameter pipe from the inside, a couple inches down from the top...because it will be as hard, if not harder to get to it from the 'outside'.
    "Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China

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