the realm of armor....

Discussion in 'Armory & Military' started by nebeltex, Feb 4, 2004.

  1. charliec

    charliec Active Member

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    I think Gil didn't pick up the point I made of a "split bamboo skewer" - that is reduce the bamboo to the diameter required then split the end of the skewer
    so that you get the same effect as Jim's brass rod with slot.

    I have a recollection that MI5 used a split bamboo splint to remove letters from intercepted post without opening the envelope by rolling up the letter around the splint and pulling it out of the envelope. Seems very low tech in the e-mail age.

    Regards,

    Charlie
  2. Gil

    Gil Active Member

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    Hi All,

    Charlie, sorry to have given you that impression..., I do use the slotted bamboo armature but find that wetting the bamboo dowel is fairly effective without the work of cutting a slot in anything let alone find the one already made for the purpose (which has already been unwittingly consumed or used to stir paint....,).

    Now you've got me thinking about raveling up the post of all things..., you know most card modelers suffer from Terminal Distraction Disorder (TDD) and now you've aided and abetted the problem.

    Best regards, Gil
  3. charliec

    charliec Active Member

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    Just to add to the TDD - the method of extracting letters was in Peter Wright's book "Spycatcher" published in the 80s.

    Regards,

    Charlie
  4. Jim Nunn

    Jim Nunn Member

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    This is what I like about a good forum! Bamboo skewer/dowels I would not have thought of using them but it’s a great Idea and I would think that it would work better then wire on smaller diameters.

    As we are talking about how detailed the models are getting lets remember the bad old days when cut lines were 1/50 inch (.5mm) wide and the paper was almost wood stock this is a very good time to be a paper modeler.
  5. rickstef

    rickstef Guest

    all this talk reminds me of a tool used for Quilling, using strips of paper to design patterns and figures and what not.

    You can check out www.quilling.com for more info

    but the tool has a slit/slot at one end, where the paper sits, and then the paper gets wound around, and the end either gets ripped off or cut off, and then glued, the ripped off edge actually gives a smoother finish.

    Reason I know about this, my mom used to do this, and I have helped her out a few times, hmmmmm a raid might be in order to acquire said tool

    Rick
  6. ARMORMAN

    ARMORMAN Guest

  7. neoneanderthal

    neoneanderthal New Member

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    ................ hmmmmm a raid might be in order to acquire said tool ............

    i can see it coming

    "Rick is Dead, Long Live Paper and Scissors" .............. :lol:
  8. Maurice

    Maurice Member

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    Jim

    Have just been looking at Peter Crow's latest IPMS pics. Always a great pleasure of course.
    How durable do you think that rocking arm suspension arrangement is likely to be.
    I really am intriqued.

    Maurice
  9. Jim Nunn

    Jim Nunn Member

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    Not very durable. The upper arms can be made to work there is a 2mm copper wire in the upper rod for strength and I did have fun with Peter when I showed him that the suspension arms and springs would work. The reason I think the designer made this capable of working is that it will allow you to adjust the suspension system so that all the wheels will sit on a surface evenly. Once you glue on the bottom arms the suspension system will not work.

    You’ll see the suspension system in detail in the next article. .
  10. nebeltex

    nebeltex Member

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    i think the longitudinal characteristics of bamboo would be ideal for a torsion bar suspension....
  11. Maurice

    Maurice Member

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    Jim

    Many thanks, I thought that might be the case.
    I look forward to the next instalment with avidlyness. :)

    Cliff

    The problem with any form of spring suspension is the need to precisely match the strength of the spring to the mass being suspended. Not easy with paper models.
    It is however quite easy with some subjects to make durable working rocking arm suspensions entirely from paper. Perhaps not entirely scale but adequate representations of the function.

    Maurice
  12. charliec

    charliec Active Member

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    I think you're right. I did some preliminary experiments with a T-70 to model the torsion bars but also to stop the suspension arms twisting off the side of the model. It's fairly easy to make a bamboo torsion bar attaching it to the model's internal frame. The problem I ran into was that the torsion bar would twist off the internal frame with the leverage from the torsion bar arm and the weight of the test rig. About that time my gumption ran out and paid work gobbled my available time so I didn't get any further.

    The problem is the old one with paper machanisms - to get adequate strength on a joint you've got to increase the joint area so that the paper doesn't machanically fail (usually by delaminating) under load. I have seen somewhere (might have been the Russian "Young Technician") an idea where the modelled torsion bars are glued to thick disks which are in turn glued to the model's frame. This looked as if it would work but I never followed it up. I have a vague recollection the Russian model was of an Su-152 - if there is any interest in this I'll see if I can dig it out.

    Regards,

    Charlie
  13. Maurice

    Maurice Member

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    There is interest in this. :)
  14. charliec

    charliec Active Member

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    I've posted a fragment of the build diagram of an Su-152 model (mentioned
    previously) - it's in my personal album. I'll figure out how to link images into posts eventually but don't have the time at the moment.

    It looks like the model was intended to have working suspension - i.e. rotating roadwheels, etc.

    Regards,

    Charlie
  15. Maurice

    Maurice Member

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    Charlie

    I'll upgrade to very interested status.
    Do you by the remotest chance have a url.

    Cheers
    Maurice
  16. rickstef

    rickstef Guest

  17. 57townsman

    57townsman Member

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    Guys,

    Here's a thought regarding the bamboo torsion bars. What if you squared off the end that will be attached to the frame and inserted it into square holes. You could laminate an extra layer or two and soak the area with CA to harden the card. Do you think that would prevent it breaking loose?

    You might be able to do something similar with the free end. Perhaps use a laminated suspension arm?

    Steve
  18. Jim Nunn

    Jim Nunn Member

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    Gentlemen

    I have been thinking about designing a paper model of the SdKfz 303A Goliath. I have loads of good information on the Golith but very little on the transport trailer. Any of you guys have any dimensions for the trailer or know of a good source of information on the web?

    Jim
  19. charliec

    charliec Active Member

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    Reasonable ideas but the medium's characteristics get you every time. Most card seems to be quite weak in shear - the usual failure mode seems to be delamination of the card. If you are going to design a joint in card to withstand shear forces about the only option is to increase the area of the joint. I haven't tried CA reinforcement very much, I suspect CA will help but the area of reinforcement would have to quite large compared to joint area. One idea I did try was to flatten the end of the bamboo torsion bar so that the joint was a slot rather than a hole. This seemed to work reasonably well but it was quite difficult to get a set of flattened end bamboo rods with similar twisting characteristics. Laminating the suspension arms seems to work quite well.

    Regards,

    Charlie
  20. Maurice

    Maurice Member

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