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Loctite alternative for a pressed on ring?

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  • #31
    Originally posted by Ian B View Post
    Nickel,

    One of the parts is cast iron - might that have enough porosity to hold some of the Loctite? The rest will indeed get scraped off.

    Ian
    At least in my experience, the cast iron will not retain enough to make any difference, if it retains any at all -- and that is highly suspect. The iron will be platically deformed when the parts go together, and that will squeeze out any loctite that remains.

    When cast iron retain oil, it is because it was soaked on it for years, and or thermally cycled in a bath of oil. (engine blocks, etc.)
    Last edited by nickel-city-fab; 08-09-2020, 12:46 PM.

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    • #32
      Originally posted by nickel-city-fab View Post

      Try genuine, 100% Maple syrup some day... you'll never want anything else again. Loads of it up here by the Canadian border. I hear Vermont also has a bunch.
      I much prefer syrup from Norway maple to syrup from Sugar maple, which is what is used commercially. Lower sugar content so longer boil, but I find it a more well rounded flavor and less cloyingly sweet. Black walnut syrup is fun, but the high pectin levels make filtering a PITA. I’m told sycamore syrup tastes like butterscotch, but never found a stand of them to tap.

      Sadly I lost access to the trees I’d been using, so have not done it in a couple years. Would make 5 gallons of maple and 2 gallons of walnut per year. Will add my gg-grandmother’s pancake recipe once I find it. Comes out closer to a crepe than what most people think of as a pancake, and much better than any I’ve ever had.

      As for the OP wanting an interference fit, well, a shrink fit /is/ an interference fit, and likely stronger than what’s possible with a press fit. 🤷‍♂️

      edit: gg-grandmother’s pancake recipe.
      Attached Files
      Last edited by AWS; 08-09-2020, 02:15 PM.

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      • #33
        Originally posted by Doozer View Post
        He already said that he chooses not to afford Loctite.
        My cheaper suggestion would be to use pancake batter.

        -Doozer
        Nothing works as well as the Tears of a Clown.

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        • #34
          There's nothing wrong with what the OP is proposing. There are several advantages, including:

          "Retaining compounds increase the strength and reliability of a traditional interference fit. Interference fits generate strength from the metal to metal contact of surface peaks, which represent only 15 percent of the total surface area of the joint. The liquid retaining compound fills the surface irregularities and clearance gaps between the two parts. It then cures to create a dense, high-strength bond that increases joint strength and achieves maximum load transmission. The cured resin increases the area of surface contact so stress distribution is improved. This enhances joint reliability, reduces equipment downtime and increases part life."

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          • #35
            Originally posted by tomato coupe View Post
            There's nothing wrong with what the OP is proposing. There are several advantages, including:

            "Retaining compounds increase the strength and reliability of a traditional interference fit. Interference fits generate strength from the metal to metal contact of surface peaks, which represent only 15 percent of the total surface area of the joint. The liquid retaining compound fills the surface irregularities and clearance gaps between the two parts. It then cures to create a dense, high-strength bond that increases joint strength and achieves maximum load transmission. The cured resin increases the area of surface contact so stress distribution is improved. This enhances joint reliability, reduces equipment downtime and increases part life."
            Frankly, I would have to see how they tested, and see it repeated by an independently verifiable outfit. 15% on an interference fit seems *extremely* low. It isn't accounting for plastic deformation and wiping off the peaks in a machined finish. Almost like somebody is trying to skew the results to fit the claims. So, no -- I don't believe that.

            I would like to see them pull one of these test pieces apart and then count the surface area and how much loctite was actually in there. That 15% maybe if you machined them with a chainsaw.

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            • #36
              This forum seems to need a certification process so that only knowledgeable people are allowed to post answers, and only on subjects that they are can prove that they are knowledgeable about. Of course, that means that the people who post questions will need a certificate on the subject matter as well as being able to pass a course in english composition.



              Personally, I've found that Tomato Coupe is generally spot on with the information he posts, so while I might ask for the source of his quote, I would not automatically doubt it's veracity.

              Dan
              At the end of the project, there is a profound difference between spare parts and extra parts.

              Location: SF East Bay.

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              • #37
                Originally posted by nickel-city-fab View Post

                Frankly, I would have to see how they tested, and see it repeated by an independently verifiable outfit. 15% on an interference fit seems *extremely* low. It isn't accounting for plastic deformation and wiping off the peaks in a machined finish. Almost like somebody is trying to skew the results to fit the claims. So, no -- I don't believe that.

                I would like to see them pull one of these test pieces apart and then count the surface area and how much loctite was actually in there. That 15% maybe if you machined them with a chainsaw.
                Someone on PM even had actual test results:
                https://www.practicalmachinist.com/v...78/index2.html

                Location: Helsinki, Finland, Europe

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                • #38
                  Originally posted by Doozer View Post

                  Typical of HSM.
                  Typical of the Internet, actually. (HSM being a specific instance of a general phenomena, but MUCH LESS BAD than many others!).

                  The quote from tomato coupe is clear a quote, likely from some manufacturer's literature, and while I have no reason to doubt it it would carry more weight and perhaps reduce the skeptical responses (or not...) if the reference was supplied.

                  Also, anyone who can't have sugar already knows all this, but while Maple Syrup contains a certain amount of simple sugars (fructose, glucose) it is still mostly sucrose, and in any case none of them are going to do you any favors if you have blood sugar issues.
                  "A machinist's (WHAP!) best friend (WHAP! WHAP!) is his hammer. (WHAP!)" - Fred Tanner, foreman, Lunenburg Foundry and Engineering machine shop, circa 1979

                  Comment


                  • #39
                    Originally posted by tomato coupe View Post
                    There's nothing wrong with what the OP is proposing. There are several advantages, including:

                    "Retaining compounds increase the strength and reliability of a traditional interference fit. Interference fits generate strength from the metal to metal contact of surface peaks, which represent only 15 percent of the total surface area of the joint. The liquid retaining compound fills the surface irregularities and clearance gaps between the two parts. It then cures to create a dense, high-strength bond that increases joint strength and achieves maximum load transmission. The cured resin increases the area of surface contact so stress distribution is improved. This enhances joint reliability, reduces equipment downtime and increases part life."
                    Well there it is a Bullseye!..... amongst 3 pages of nothingness, foot shooting and a good pancake recipe. lol

                    Additionally if the ring is thin walled it will never achieve a high percentage of contact no matter how tight of an interference or shrink fit because the ring will yield, permanently stretch before achieving more contact area.
                    Diminishing returns on that uber tight press or shrink fit that everyone is all excited about.

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                    • #40
                      Originally posted by mickeyf View Post

                      Typical of the Internet, actually. (HSM being a specific instance of a general phenomena, but MUCH LESS BAD than many others!).

                      The quote from tomato coupe is clear a quote, likely from some manufacturer's literature, and while I have no reason to doubt it it would carry more weight and perhaps reduce the skeptical responses (or not...) if the reference was supplied.

                      Google, it is from Loctite.

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                      • #41
                        Originally posted by MattiJ View Post

                        Someone on PM even had actual test results:
                        https://www.practicalmachinist.com/v...78/index2.html
                        Thank you. Cijuanni, TomatoCoupe -- I'm sorry about that, I am skeptical of big claims. It seems somebody on PM actually did test it, and showed that it works. I apologize for being an ass first thing in the morning.

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                        • #42
                          I apologize for being an ass first thing in the morning.
                          I try to avoid that by not turning on my computer until later in the day...
                          "A machinist's (WHAP!) best friend (WHAP! WHAP!) is his hammer. (WHAP!)" - Fred Tanner, foreman, Lunenburg Foundry and Engineering machine shop, circa 1979

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                          • #43
                            Originally posted by cijuanni View Post
                            .............
                            You know, where a light interference fit, banged on with a hammer WITH an adhesive would be ideal.

                            .............
                            Well, what you said right there is REALLY HELPFUL. I mean it.

                            For that situation, adding Loctite is perfectly good and actually I think it is a good idea. Knowing that is what you meant would have cleared up a lot.

                            See, "interference fit" produces a mental picture among many, if not most, of a fit that takes some serious pressure to achieve. Someone mentioned steam locomotive wheels, which were pressed on with a couple hundred tons pressure. Even f it only takes a couple of tons pressure, it is still a metal displacing fit.

                            That type of fit would scrape off most if not all of any adhesive, and the addition would not be likely to help much. I saw the PM results, and I am wondering about it. Seems legit, the question is whether it matters if you already have enough "grab" to do what is needed. As for the shrink fit, maybe not too good if the temp for the shrink is high.

                            But a fit just tight enough to bang on with a hammer is only a minimal interference, and significant amounts of the adhesive should stay on and be effective. I'd do it, it's a good plan. The adhesive would definitely add both holding power, and sealing against water or other corrosives.
                            Last edited by J Tiers; 08-09-2020, 05:27 PM.
                            1601

                            Keep eye on ball.
                            Hashim Khan

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                            • #44
                              Originally posted by J Tiers View Post

                              Well, what you said right there is REALLY HELPFUL. I mean it.

                              For that situation, adding Loctite is perfectly good and actually I think it is a good idea. Knowing that is what you meant would have cleared up a lot.

                              See, "interference fit" produces a mental picture among many, if not most, of a fit that takes some serious pressure to achieve. Someone mentioned steam locomotive wheels, which were pressed on with a couple hundred tons pressure. Even f it only takes a couple of tons pressure, it is still a metal displacing fit.

                              That type of fit would scrape off most if not all of any adhesive, and the addition would not be likely to help much. I saw the PM results, and I am wondering about it. Seems legit, the question is whether it matters if you already have enough "grab" to do what is needed. As for the shrink fit, maybe not too good if the temp for the shrink is high.

                              But a fit just tight enough to bang on with a hammer is only a minimal interference, and significant amounts of the adhesive should stay on and be effective. I'd do it, it's a good plan. The adhesive would definitely add both holding power, and sealing against water or other corrosives.
                              Yes, THIS. When I think interference fit, I think of a 100-ton hydraulic press (most jobs only take between 5 and 20 tons)
                              Last edited by nickel-city-fab; 08-09-2020, 05:48 PM.

                              Comment


                              • #45
                                Originally posted by danlb View Post
                                This forum seems to need a certification process so that only knowledgeable people are allowed to post answers, and only on subjects that they are can prove that they are knowledgeable about. Of course, that means that the people who post questions will need a certificate on the subject matter as well as being able to pass a course in english composition.



                                Personally, I've found that Tomato Coupe is generally spot on with the information he posts, so while I might ask for the source of his quote, I would not automatically doubt it's veracity.

                                Dan
                                You should found a test lab that will answer the many pressing questions often asked by home shop machinists such as.

                                I picked this material up for free, what is it? Have the customer send DanLabs™ a sample and do an assay.

                                Alternative to Loctite for a press fit? Have the customer produce several test parts for DanLabs™ to perform destructive testing on, pull them until the joint fails and record the results.

                                There is no reason that you can not lose a great deal of money in a short time span with this business model. (-:

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