Jump to content

Loft

TU Member
  • Posts

    12
  • Joined

  • Last visited

Loft's Achievements

Newbie

Newbie (1/14)

4

Reputation

  1. Go to Google. Type searchword and th en type: site:.tackleunderground.com
  2. Try youtube, marling baits has some videos where he is making bills, ans solarfall baits has a video on making foils. But check out their videos in general. Loft
  3. Loft

    Moment Of Inertia

    Not nesesarrily.If your way works for you, i don't se any reason to try and fix it. The reason for this thread, was to explain the effect of moment of inertia. The weighing process was just a part of the process of getting there Loft
  4. Loft

    Moment Of Inertia

    You should be able to find a reloading scale much cheaper than 184 USD If it is a digital like a kitchen scale, then an improvised stand should do And don't use that kinda money based on my theories, i'd be ashamed if it didn't work How do other guys manage the extreamely light lures? Loft
  5. Loft

    Moment Of Inertia

    Mark The moment of inertia also keeps your glidebaits going straight. Loft
  6. Loft

    Moment Of Inertia

    My mistake. Forget about the 2.5 i just forgot to erase it after testing the equation. Loft
  7. Loft

    Moment Of Inertia

    Hi I actually didn't put that much thought into it, i was just thinking about overall movement. I'll see if i can rewrite it to be more correct Thank you for the reply Loft
  8. Moment of inertia Hello all J My experience as a lurebuilder is limited to just started, but I have been following the hobby for some years now, meaning this is theoretical not pragmatic. I was asked to elaborate the basics of moment of inertia (via PM), after mentioning it in another thread, and thought I’d make a thread so I wouldn’t misinform the guy, without someone to draw the BS card, or come with the real world way of doing stuff when it is applied to lurebuilding. Moment of inertia: Is the ability of an object to resist being rotated. (My own way of putting it, I don’t know the correct definition). To understand the meaning of it, imagine a broomstick, place two weights of 5lbs. in each, and the same broomstick with the two weights placed in the middle of the broomstick. They have the same weight, the same center of gravity (CG), but the one with weights in the middle will be much easier to rotate around the CG. The easiest way I can come up with to apply this to lurebuilding. Is if we think about copying a lure. Make the lure the exact same shape, and put the weight so it sinks the same way (the lure has the same: shape (the same center of lift), volume (the same amount of lift), mass (weight) and CG). This way everything seems to be right. However, it might act different. This is where the theory of the imaginary broomstick comes into play. If the lure action is too fast move the weights further apart, and the other way around if the action is too slow. There is no easy way (I know of) to measure moment of inertia. However, if the lure in the example above was a glidebait, a couple of prototypes might get you there. But if it was a multi joint swimbait, then the amount of variables to make the replica swim the same nearly gives me a headache. (remember, I’m lazy and have never tried making a swimbait replica (infact I’ve never made a working wooden lure L)) Finding the center of gravity Lay the lure on the side on a narrow flat object. When the lure does not tip off the CG is inside the edges of the object. If this is done in two opposite ways the CG is the point on the lure that was on the object both times. If the above method do not work with a lure (due to the shape of the lure). The CG can be found by weighing both ends of a lure on a fine scale, while holding the lure level. Then the CG can be calculated. This method does not give the height of the CG in the lure. Finding the center of lift The center of lift (or buoyancy). Is found by finding the point where the bait displaces half of it’s volume, in two different axis’s (like finding CG by the first method described above). If it is a bait of a consistent material, with no hardware installed, the CG and CL is the same point. The baits level in the water If we leave out the hydrodynamics. The level of the lure when it sits in the water, will be with the CG directly below the CL (a steel leader or movement of the lure might change this). Changing the CG with ballast If the weight, CL, CG, the desired weight and the desired level in the water (resulting CG) is known. Then the weight of the ballast is calculated by subtracting the actual weight of the lure, from the desired (this way do not account for loss in weight when drilling). The place to put that ballast is found in the following way: Now back to moment of inertia. We have the amount of ballast figured out, and where in the lure we want the CG of that ballast. If the entire ballast is placed at the place of the CG the lure will have a low moment of inertia, and change direction easily. If that is not wanted and a slow action is desired, the weight needs to be split out. When splitting the weight and keeping the same CG, the weight multiplied with distance (to CG) of both weights need to be the same: d1*B1 = d2*B2 If the distances is desired the weights to place at each point is calculated this way: B1 = BTOT*d2/(d1+d2) B2 = BTOT*d1/(d1+d2) (d1/d2 being the distances, BTOT being the total weight of the ballast and B1/B2 being the weight of the individual ballasts) Hope it gives a little sense, both theory, and the entire text (I'm from Denmark, and I'm better at mathematical stuff, than with grammar, and foreign languages)
  9. The factor 8 is the increase in volume if you multiply all three dimensions by two. If you want the same boyancy you wan't to hit that factor 8 in weight also. The action will also be affected by center of gravity and the moment of inertia. Hope it gives just a little sense Loft
  10. When you double the dimentions, the weighe get 8 times as high (1^3 = 1 2^3 =8 )
  11. There is an introduction to release tackle here: http://www.bursell.dk/articles/fishing/saltwater/coastfishing/show/279 Loft
  12. Propobly not the obvious choice, but you could make a release tackle, then you only need to worry about durability for cast and retreiwe. There ofcourse some cons to it too, but it gives better hookup rates with some species too. Loft
×
×
  • Create New...
Top