Opposed Twin Coil swap….TG and others…

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  • RICHARD A. WHITE

    US Member - 2 Years
    Replies: 1802
    Topics: 137
    #896

    I was prepared to post his on the "other" forum one night when I realized like all others that the dam board got whacked. So hats off to the Webmaster for getting us our communication tool back up and running. Ok I think TG was the one that started this thread on the other board and I wished to give more info on what I have successfully completed previously. Some photos were published by Jim Moffatt once in the April 2008 Outboarder, and again in the October 2010. I with Jim’s guidance installed 2 50’s OMC coils in my Eisemann model 82D mag as seen on the right. The mag on the left is the Wico Mag.. notice how little space available to install 2 coils on that one.. I have ideas but my evil genius quota is spent for the day… I hate when work uses all my special powers 🙂 Oh well this opens up more conversations on this topic which has been well received.

    Ok here are the process photos for what I did when converting the Eisemann mag over to OMC coils.

    Here in this photo you will see the laminations after I removed all the old primary and secondary wire, That took a bit of time, I was surprised how much was actually there. Notice the lam’s are rounded, I guess that made it easier to wind the wire that way.

    Make special note here, notice just below the "e" in the word bend, you will see a hole. It is absolutely critical that that hole be placed into the laminations BEFORE you cut separate or disassemble these laminations. That hole was in my laminations already so I did not need to add it, but if you DON’T have one, MAKE ONE there. I placed the core in my mill vise and machined the core to .01 under the core opening in the OMC coils. You will find that you now have more plates than will fit in the OMC coils, Fear not my good friends, this is no big deal as we only need enough plates to fill the OMC core opening and that is it. I found that 13 plates made for a good snug fit. So I kept the 13 bottom plates, out of 18 total plates. I then placed the laminations in order starting with the top plate and labeled it #1.. genius huh, LOL, then continued to the last which I labeled 13. At this point is where Jim Moffatt offered some very good advice. He suggested I cut the laminations alternating from side to side so the seems were not all on top of each other effectively creating a sandwich of laminations…flipping brilliant. So I marked each one so that the cut would be hidden inside of each coil. See photo below…

    Notice the pcs on each side of my 13 plates…… see them, ignore them you won’t need them, it is how I did mine but realized they were not needed, but only after I put it all together.

    Next I needed to replace the rivets that were originally used to hold the laminations together. See the following photo for my interpretation of rivets. Hmmm looks like crap and they are too tall, LOL Ok here is what you do Make a hollow rivet so that you can use a machine screw to hold down the unit when finished, I will remake the rivets on mine and add an oil sling protector to ensure the oil the passed thru the upper main bearing does NOT get on the points… See my hack rivets below:

    More words of advice, slightly ever so slightly buff the edge marked with the red arrows, on both the upper side and the lower side of the odd and even plates. See photo below:

    Next, I placed the even numbered plates on one of my "rivets" and the odd numbered one on the other rivet, now comes the fun inserting then in to the coils.. See photo below, but note, BOTH coils MUST face same direction, some hocus pocus BS that Jim tried to explain, I did not argue I just did it, would recommend you follow 🙂 Haha See photo below:

    Now once you have got BOTH side inserted into each coil, you need merely to "slide" the blade interlocking them, now be mindful of which one is on top of which one. When installed properly you will be able to slide the 2 halves together and the little hole you HAD to drill in the beginning or was already there should line up… yeah NOW is when it is important, and it Makes absolutely dam sure the WIDTH of the coil is the same. See it IS important, LOL…

    See photo below:

    See the pin in between the 2 coils, you can find a rivet, but I would recommend a machine screw, a little Loctite on the nut, removable of course and you have done it.

    Understand a few simple rules…:

    1. If the space is available pretty much any smaller universal coil will work, and the caveat to that is, if you use the 50’s OMC coils, use ONE 50’s OMC condenser. If you find some other coil that fits, GET the correct and matching condenser for THAT coil, and all will be well.

    2. Both coils must be facing the same direction, in other words the "potting" on both coils must be on the same side. the direction the High tension lead points is not relevant.

    I really hope this helps those that want to do this. And I hope I have not offended anyone..

    Thanks and good night, any and all questions will be answered as promptly and professionally,LOL…LOL…I said professionally.

    Ok I will give it my best shot.

    Regards

    Richard White
    M.O.B. Chapter President

    http://www.richardsoutboardtools.com
    classicomctools@gmail.com


    david-bartlett


    Replies: 1204
    Topics: 97
    #11774

    Richard,

    Great pics and explanation. Thank you.


    Mumbles

    Canada Member - 2 Years
    Replies: 5171
    Topics: 276
    #11776

    Nice work. I admire what you’ve done! 😎

    Just a thought, but could you use ‘sex bolts’ which are used in joinery instead of making up rivets? They are two piece, male and female, and just screw together.


    dan-in-tn

    US Member - 2 Years
    Replies: 961
    Topics: 78
    #11777

    Thanks Richard. I didn’t have the heart to ask for this info again not knowing how you were feeling. Hope all is well! Thanks for putting it on the new site. I managed to register, but changed my name by accident, so now it is t2stroke, previously BigBird! I don’t know if all this name changing is good, but hey we will get to know each other again!

    Dan in TN


    Mumbles

    Canada Member - 2 Years
    Replies: 5171
    Topics: 276
    #11778
    quote t2stroke:

    Thanks Richard. I didn’t have the heart to ask for this info again not knowing how you were feeling. Hope all is well! Thanks for putting it on the new site. I managed to register, but changed my name by accident, so now it is t2stroke, previously BigBird! I don’t know if all this name changing is good, but hey we will get to know each other again!

    Dan in TN

    Dan, just go back and edit your profile!


    RICHARD A. WHITE

    US Member - 2 Years
    Replies: 1802
    Topics: 137
    #11795
    quote Mumbles:

    Nice work. I admire what you’ve done! 😎

    Just a thought, but could you use ‘sex bolts’ which are used in joinery instead of making up rivets? They are two piece, male and female, and just screw together.

    The base is already threaded so I just made hollow tubes/"rivets"..

    http://www.richardsoutboardtools.com
    classicomctools@gmail.com


    Buccaneer

    US Member - 1 Year
    Replies: 5085
    Topics: 831
    #11807

    I replied to this post last night, but I don’t see it. Is there a delay
    or message approval in the system?
    Anyway, Great write-up Richard!
    Just one question…… "Why not shine up the laminations?",
    instead of just lightly buffing the ends?
    Thanks, TG

    Prepare to be boarded!


    RICHARD A. WHITE

    US Member - 2 Years
    Replies: 1802
    Topics: 137
    #11815
    quote Buccaneer:

    I replied to this post last night, but I don’t see it. Is there a delay
    or message approval in the system?
    Anyway, Great write-up Richard!
    Just one question…… “Why not shine up the laminations?”,
    instead of just lightly buffing the ends?
    Thanks, TG

    The buffing of the ends is to allow them to "mesh" easier when putting the 2 halves together. My thought was that if I said clean them off one might interpret that as remove all residue, which might remove the coating on the metal. Does that matter??? I don’t know, but to me laminated metal is the base metal laminated between coatings of some sort. I was trying to avoid removing that coating.

    http://www.richardsoutboardtools.com
    classicomctools@gmail.com


    Buccaneer

    US Member - 1 Year
    Replies: 5085
    Topics: 831
    #11821

    Richard, I tried searching for "magneto laminations material", etc., to see
    what coatings or special properties the metal is made of, but only
    came up with a bunch of engineering gobbly goop!

    Prepare to be boarded!


    mr-asa

    US Member - 2 Years
    Replies: 794
    Topics: 138
    #11823

    What sort of engineering gobbly goop? We have some smart folks here, might be able to figure it out


    phil

    US Member - 2 Years
    Replies: 169
    Topics: 19
    #11825

    As I understand it the coating is put on the laminations to avoid what are called "hysteresis" losses. Essentially to cut down on " eddy " currents within the metal of the coil core, dividing into laminations also helps in this regard, as opposed to having the core of solid metal.
    The above losses if not addressed tend to heat the core. Of course, we all know of older coils and coil designs that do have solid cores.
    It seems that magneto coils are small enough that this may not be much of an issue, it certainly is an issue on transformers that handle a large amount of power.

    http://www.omc-boats.org
    http://www.aerocraft-boats.org


    joecb

    US Member - 2 Years
    Replies: 498
    Topics: 63
    #11831

    Steel used for magnetic core laminations is soft steel, specifically low carbon high silicon steel.. no coating to the best of my knowledge.
    Joe B


    jnjvan

    US Member - 2 Years
    Replies: 42
    Topics: 1
    #11836

    Phil and Joe are both correct. Some lams are coated, many are not. Those that are not coated rely on a thin oxide layer to provide some resistance between lams. If these is no resistance, or if the material was not laminated, eddy current losses would reduce the efficiency of the coil. The eddy currents circulate perpendicular to the axis of the core, hence the effectiveness of laminating the core.


    RICHARD A. WHITE

    US Member - 2 Years
    Replies: 1802
    Topics: 137
    #11838
    quote Buccaneer:

    Richard, I tried searching for “magneto laminations material”, etc., to see
    what coatings or special properties the metal is made of, but only
    came up with a bunch of engineering gobbly goop!

    Yup, exactly what I came up with so I figured if it worked for that long I aint gonna muck it up 🙂

    http://www.richardsoutboardtools.com
    classicomctools@gmail.com


    Buccaneer

    US Member - 1 Year
    Replies: 5085
    Topics: 831
    #11844

    Said Gobbly Goop…..
    "Explicit nonlinear homogenization for magneto-electro-elastic laminated materials
    Stefano Giordano
    Mechanics Research Communications
    ABSTRACT In this work we propose an explicit procedure for the homogenization of laminated magneto-electro-elastic nonlinear materials. It means that we determine the effective response of a multilayered structure composed of materials with an arbitrarily nonlinear and anisotropic coupled behavior. In order to obtain a general theory, we take into consideration an arbitrary lamination direction, which is useful to exploit the anisotropic character of components. This technique is characterized by closed form expressions, which can be simply implemented through the basic operations of tensor calculus. To conclude, we discuss some particular cases and various applications."

    Prepare to be boarded!

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