1/48 Bristol Pegasus design and build

Discussion in 'Aircraft & Aviation' started by dubious, Jun 19, 2013.

  1. dubious

    dubious New Member

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    I started working on a 1/48 Supermarine Walrus (by Ladndad) and decided it needed a more detailed engine, Here are a few pics of the prototype I am working on and the dxf file that I built it from(mostly, it has gone through a number of revisions).
    I have only fully completed 1 cylinder so far . it took a while to get a valve cover design that I could build and looked half right, it only has 2 valves instead of the proper 4 and no exhaust pipes currently, though there are some in the plan I couldn't roll them tight enough on the 32Lb bond (120 g/m^2) paper that I am using.
    Ill try to clean up the dxf file and produce a pdf soon

    FWIW I used QCAD to create the dxf it is 1"=1" and printed at 1/48 scale

    Attached Files:

  2. Gixergs

    Gixergs Well-Known Member

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    Very nice and a very useful model to have, I look forward to seeing it in the Walrus
  3. zathros

    zathros -----SENIOR---- Administrator

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    Very nice. I look forward to seeing this completed! :)
  4. dubious

    dubious New Member

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    Here is a PDF of the engine at its current state of development. I'm not sure when I'll get time to build it, when I do I will post pictures.

    As far as the walrus goes, I'm not having great progress, the top fusalage doesn't seem to line up too well and I think I'm going to end up with a hook to the left on the nose, Ill have to try again, perhaps with a keel and former substructure?

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  5. zathros

    zathros -----SENIOR---- Administrator

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    Depending on when the model was made, I have found on many older models the fit is questionable. The engine looks nice. I wish to put it in the "Downloads" section, you could if you wish. If left in the thread, it will get lost over time. :)
  6. dubious

    dubious New Member

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    The download section sounds like the right place for it :).
    I'll put it there after I actually build it, just in case it needs any more tweaking
  7. zathros

    zathros -----SENIOR---- Administrator

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    Thank You, I (We, I'm sure) appreciate that. A couple of different scales might be nice. :)
  8. dubious

    dubious New Member

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    the final build is going slow, I have the crankcase together and most of the parts cut out, hopefully I will find time in the next few days to finish it.

    If anyone is interested in a different scale let me know, you may be called on for test build duty.

    On the airframe side, does anybody know of other walrus plans? the fuselage on the ladndad one seems to lack symmetry :(
  9. dubious

    dubious New Member

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    Still have not finished the build, but I have reworked the gearbox and the valve/valve-cover arrangement(4 valves per cylinder now) and added the oil sump.

    Attached Files:

  10. zathros

    zathros -----SENIOR---- Administrator

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    That is a nice looking engine. It would be cool to use in some kind of steampunk model, or a kitbash, and, of course, a genuine model of an airplane. :)
  11. dubious

    dubious New Member

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    Well he final(?) build is finally starting to come together, here is a progress shot

    Attached Files:

  12. zathros

    zathros -----SENIOR---- Administrator

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    That is a great looking engine!! I can imagine it being used on many models! :)
  13. dubious

    dubious New Member

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    Sadly it looks like many of the uses of this engine in a tractor configuration have a large exhaust manifold that hides a bunch of the engine, and a cowl

    but the plan is to hang it in the middle of a Supermarine Walrus

    On the positive side, It is just about the same shape as a Bristol Mercury
  14. zathros

    zathros -----SENIOR---- Administrator

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    You have to hang that cowl and exhaust manifold off of something! :)
  15. dubious

    dubious New Member

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    And final pictures, I didn't add the exhaust stacks, too tough to roll printed on cardstock, should work on 20lb bond

    I still need to work on edge coloring and centering parts better :(

    If anyone builds this, I would love to see pictures

    Attached Files:

  16. zathros

    zathros -----SENIOR---- Administrator

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    I would look for small hollow aluminum tubing at a Hobby store for the exhaust. You can bend it easily without deforming it by filling it with sand, epoxy/seal each end, and when you bend it, it will not kink. ZipDry glue will strongly hold metal to paper. A small hole drill into the cylinder head would also help. It looks great! This can be used in so many models, even as a generic engine for a fantasy Steam Punk type model. I love components like this. I imagine a lot of components, kind of like a shelf people can pick up and just make something out of their head without having to make every part. :)