Gt/tuna lure build help

Discussion in 'Lure Building' started by Jdubbs75, Jan 26, 2020.

  1. Kipi

    Kipi Well-Known Member

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    Not sure that the depth of cup will add performance value against work input... But the sharpness of the lip is awesome... That will pay dividends for the angler and his physical effort in the "pop".

    Ideally, you would want to displace maximum water with minimum effort... But it will take one with more scientific background than me to make the analysis. Bottom line is... Have fun building lures, and have the incredibly deep sense of satisfaction catching fish with them.
     
  2. DenisB

    DenisB Senior Member

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    Kool.............local name for a standard overhead cast..............got it .
     

  3. DenisB

    DenisB Senior Member

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    The things that most affect the effort in popping ( drag if you will )are the surface area of the head face ( determined by diameter ) & how deep it sits in the water. The shape of the cup affects the spray pattern & the "bloop", more than lure drag.
    whatever the shape of the cup the bottom of the cup pulls the lure deeper in the water when the lure is pulled , the shape affects how quickly the lure gets submerged. Once submerged the drag is proportionate to cup diameter/surface area..
    the shape of the cup gives an appearance of affecting drag, but its really an impression generated by the rate of accelleration of the drag as the lure is pulled rather than the actual level of drag.............our senses are sort of fooling us in the impression we get.

    ie a Nomad " Chug Norris" with a big head will always require harder work than a slim profile popper like Masthead's in post #19...........where the lures are the same basic length.

    FWIW
     
  4. Jdubbs75

    Jdubbs75 Member

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    Every coat i put on i am getting this looks actually like bubbles more then dust but i might be wrong dennis. I tried a torch on cup of epoxy quickly and lightly on turning lure but seems like bubbles show up later as the lure is turning and i am not around. Any opinions on how to get rid of this. This is seal coat so not to big of deal but on top coat would like to minimize it a bit more.

    I know you probably can’t get it perfect but decrease the amount of them.
     

    Attached Files:

  5. Kipi

    Kipi Well-Known Member

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    Something you really want to avoid is temperature fluctuations... In particular, a rise in temp after coating. Wood has heaps of air in it that will expand when heated and exit the pores causing bubbles in the finish.
     
  6. DenisB

    DenisB Senior Member

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    This is true about the porous nature of wood.
    The trick is light heating of epoxy after its applied as it heats the surface of the wood , expands the air in the timber grain near the surface & bubbles easily pass thru the epoxy coating while exposed to warm CO2 ( the burnt butane or alcohol ).............Warmth & CO2 lowers the surface tension & ambient partial pressure which is what allows the bubbles to easily break thru the epoxy surface.
    as the surface of the lure cools quickly& causes light suction in the porous surface of the wood after light heating you have to be very unlucky for ambient air pressure to drop or ambient temp to rise enough & cause more air in the timber porous grain to expand & cause more bubbles before the epoxy can jell enough to resist bubble formation.
    1. heated curing box thermostat controlled solves a bunch of problems .
    2. If not available avoid glossing when there is risk of a cold front arriving within 3-4 hrs of intended coating.
    3.
    Glossing when there is high humidity should also be avoided( can cause blushing).
    FWIW
     
  7. Jdubbs75

    Jdubbs75 Member

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    Thanks guys i really appreciate the advice and knowledge and hopefully this thread will answer others questions as well when searching on here. Working in a garage with space heaters blowing crap everywhere so that is a definite horrible outcome. So i bought heat lamps and going to maybe construct a cure box if i have a enough scrap laying around then try it again. I will post results after new tests are done. Have a few days off work due to being at ground zero of the coronavirus so i get to play a bit as long as i don’t get the sickness.
     
  8. Nas

    Nas Member

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    what instrument is used to make these cups , can you state or show picture or both .Will it work on resn?
     
  9. Kipi

    Kipi Well-Known Member

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    I got these off eBay, though I see the seller is no longer listed. But do a search, someone else will be selling them. They're fairly expensive but effective. For an idea of scale, I think the largest is about 2" and the smaller round is 1". Wood Burrs.jpg
     
  10. Nas

    Nas Member

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    Hi Kipi ,
    Thanks for your quick response , i have searched for cup drill bits and not come across anything like these. Any suggestion where to look or what they are called?
     
  11. Kipi

    Kipi Well-Known Member

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    Hi Nas. Sorry I'm only getting back to you now... I've been searching high and low for these but am coming up empty handed. The correspondence I received from the seller described things as such:

    • 1-3/4" CARVING CUP CR13470 MIdium RED - Adapter included 1/4" shaft #321500921748
    • Sphere 14S1Y 1 Inch 1 Inch Yellow 1/4 inch shaft Item #: 221413231191
    • BZ23450 2" Buzzout Wheels Extra Fine Yellow 2"x3/4" Adapter Included 1/4" Dia Item #: 221372991873

    There was a refund by the supplier and they mailed it to me from [email protected]

    This wasn't the seller tho... Seller was Kookiel44 but he doesn't appear to sell on the bay any more.
     
  12. Nas

    Nas Member

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    Hi Kipi,
    Thank you for your efforts much appreciated
    Best Regards
    Nas
     
  13. Nas

    Nas Member

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    Hi Again, Sabburtooth.com check this out , but don't know if they are still in business
     
  14. Kipi

    Kipi Well-Known Member

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  15. Kim

    Kim Senior Member Supporting Member

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  16. Ananthamurthy

    Ananthamurthy New Member

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    hi man i'm new to lure building but i know this when epoxy penetrates it does bubble up to avoid you need to apply base coat means apply very thin this coat and torch it thin means very thin it will penetrat and let it dry and the second coat will be fine
     
  17. DenisB

    DenisB Senior Member

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    A.......y
    painting technique affects epoxy. the high viscosity & high surface tension of epoxy causes bubble entrainment when too much brushing is done applying the coating.
    this was Jdubbs problem.............like many other first time epoxy users he was applying like a wall/ceiling paint............apply then work it in & level off.
    This doesn't work well with epoxies...........the more you work it the more air bubbles you get...............whether you are glossing a fishing rod wraps with rod epoxy or glossing a lure with Etex or similar. They prefer a flooded brush with slow application followed by a very light touch levelling once the complete coated area is covered ( usually 'levelled' perpendicular to the application coating direction).
    Only a very light touch is required on the 'levelling' strokes as the high surface tension of epoxy grabs the applied epoxy & drags it with the brush stroke..........you don't need to push hard into the applied epoxy to spread it around. Same reason why you don't need to rub "self-levelling" epoxy into the substrate to get good adhesion ( on a properly prepared surface)..........the high surface tension of the liquid epoxy enables it to "grab" the substrate surface.
    Epoxy glosses are self-leveling, so require only general brush spreading level..........they will gloss smooth on a horizontal rotisserie ( for both rods & lures)........or using a vertical drip technique for lures.
    vertical drip technique produces a thinner coating than rotisserie.........thats all.

    low viscosity epoxy wood sealers appreciate the same flooded brush technique, but require light spreading & levelling of each brushload as they absorb into the surface rapidly & very quickly become tacky...............the more you work each brushload around the more rippling of the finished coating you will get.............you need to plan your approach to applying epoxy wood sealers so that you are constantly maintaining a 'wet edge' to the job as the coated area progresses. You don't need to maintain a 'wet edge' approach when applying gloss epoxies as they are very slow drying..........so it is unnecessary.

    Have at it & have fun...........don't make lurebuilding hard work !!!!!
     
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