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Vodkaman

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Everything posted by Vodkaman

  1. Hillbilly voodoo – Good comments. In my early days of lure design and building, I too had a ‘wall of shame’, lures that just did not work. Once I understood more about what the water was doing, I was able to take the lures off the wall. Duplicating a successful hand carved lure is a problem. I am actually considering writing a post about ‘reverse engineering’, the fancy word for ‘copying’. The root of the problem is that it is very difficult to accurately duplicate the exact 3D shape, it will look close, but any slight errors will change things. You can get all the features close enough by eye; shape, lip size and position, ballast location, hook positions, tow eye position and so on. But, the one thing that you have not duplicated is the buoyancy of the lure. If you get say the width wrong by 0.5mm too big then the volume of the body increases by as much as 5%. Add to this all the other body shape dimensions that were very slightly off, and you end up with a significant error, and a lure that floats or sinks faster. Also, add to this any differences in the wood density. If the buoyancy is wrong it does not mean you have to alter the body shape, you can simply adjust the ballast to achieve the required buoyancy. To determine the buoyancy; you could float the lure and make a note of how much sticks out of the water, or you could measure more accurately by performing the ‘Archimedes dunk test’ which I posted under the same name. Yes, sounds complicated, but once you have done it a couple of times it really is easy. Each feature of the lure generally has two adjusters. As stated in the previous paragraph; body shape and ballast are matching adjusters, and ballast is easier to adjust than body shape. Another adjuster pair is lip length and tow eye location, decide which adjuster is easier to adjust. KennyP – thanks for the nice comments, and good luck with your project. CNC – this stuff is not for everyone, it is just another way of looking at things. People know what I write about, if not interested then simply move on. Experience is a powerful tool, but it takes many years to attain. On the other hand, knowledge is a lot easier and faster to attain. Put the two together. Dave
  2. CNC - my point exactly. Perhaps I did not write it clearly enough, not my strong point. We have just as much chance of coming up with something unique, a new idea, a solution to an enigma as anyone else regardless of smarts. Dave
  3. I would appreciate it if all those that requested copies of the ballast calculator brought feedback and suggestions of improvements to the table, either by PM or posted here. Many thanks for the encouraging response. Dave
  4. We all use different top coats. I like D2T so about an hour is more than enough. If you have a basic workshop, it is very easy to set up a simple turner. Do some reading, buy a slow motor and get stuck in. It is strangely rewarding to see your work turning Dave
  5. I watch a video with a coated lure by my side, clamped in a pair of Spencer-Wells artery clamping forceps. I up-end the lure every 5 minutes and get pretty good results. It is very little effort having gone to the trouble of building the lure in the first place. It is just a part of the process. Dave
  6. I suspect that you are scraping the sides of the cup when making the final pour. This is bad practice as you pick up unmixed resin. It is better to mix a little extra so that you do not have to scrape. I do understand your problems with only 2.5 minutes for mixing. I prefer a longer cure resin and mix the MBs in after mixing parts A & B. But not possible with such a short time. Dave
  7. Here are three examples of the application, aiming for neutral buoyancy. In each case the ballast adjustment is shown in the green box. It looks like the ballast adjustment values don’t add up, but this is because the material removed for the ballast hole(s) is taken into consideration. I measured and weighed a block of the body material: 1.5cm x 1.5cm x 4xm = 9cm³ Weight = 2.39g. EX1 – a completed lure with 10g ballast installed. volume (Archimedes) = 21.2 cm³. weight = 18.79g. EX2 – a completed lure with no ballast installed. volume (Archimedes) = 21.2 cm³. weight = 8.79g. EX3 – a completed lure with 16g ballast installed. volume (Archimedes) = 21.2 cm³. weight = 24.79g.
  8. I have done a lot of work on ballast calculators in the past. I have never offered them up for use by TU members because I considered them complicated and clumsy. This one however, I consider to be very slick and versatile. You can enter data from a first prototype and it will calculate how much ballast you need to add or subtract to achieve the buoyancy that you desire, be it slow sink, neutral or float. Boxes 1 and 2 are merely to collect data on the body material in order to obtain the material density. Boxes 3 and 4 are measured from a completed lure with hardware, hooks and topcoat. Box 5 is your desired buoyancy, 100% = neutral buoyancy. Box 6 is the density of the ballast. This can be changed if not using lead. The calculation takes into account the body material removed or added to make room for the ballast. PM your email to me if you would like to try this spreadsheet. Dave
  9. If you have a blank body and a fully assembled body with all hardware attached, and a gram scale, then it is possible to calculate the weight of micro-balloons required to add to the resin mix in order to achieve neutral density. a gram scale with 0.01g increment would be nice, but 0.1g would definitely get you close. The solution is complicated and so I have written a spreadsheet to make it simple. You will need to read up the post on Archimedes dunk test but it is really not difficult, as others who have tried it will tell you. If you or anyone would like to try the spreadsheet then PM me your email address and I will send it. Dave
  10. I agree heat or vacuum forming is the way to go. Dave
  11. There was another recent post on the same subject. Basically, you need to model your lure body in CAD in order to communicate with the printer. There is no way around this. Learning CAD is daunting, but is not that difficult if you are prepared to put in the hours. I will add; if you go to the trouble of teaching yourself CAD, you will have to use it regularly even if you do not have a project on the go. In between projects, I like to get in at least an hour or two per week. Fail to take this advice and you will have to learn from scratch every time you start a new project. CAD is NOT like riding a bicycle. Dave
  12. Vodkaman

    1 lb ball

    Barrel twist is the best solution, giving more trapped glue and more 'teeth' to hold. As for testing; I hung a bucket with 20Ltr of water (44Lb) for 24 hours. It held and that was good enough to satisfy me. Dave
  13. The Japanese pull saw is the best, giving the most control. Dave
  14. Vodkaman

    1 lb ball

    The answer is 96Lbs. If you double the stretch then you halve the load: 0.5 = 96Lbs 1.0 = 48Lbs 2.0 = 24Lbs Find a way to measure that momentary stretch and an accurate figure can be calculated. I can send anyone a simple spreadsheet were you can enter your 3 numbers and get the answer. Just pm me your email and I will send. Dave
  15. Vodkaman

    1 lb ball

    Wayne - I understand the age thing, feeling it somewhat myself, though you do have 13 years on me Theoretically, the load at the end of the drop with zero flex would be infinite! Of course there is always some flex, which makes the theoretical situation rather silly and incomprehensible. In terms of science, it all comes down to the law of 'conservation of energy'. What this means is that energy cannot be created or destroyed. You do work (input energy) when you raise the ball, you burned calories. When the ball drops the energy has to go somewhere, usually as heat. Your initial question is entirely reasonable, a question that I explored myself. BUT, it just doesn't work like that. If we knew how much the line stretches during the fall, we could actually come up with a number to represent the load. I am not an expert here, this is just my interpretation of the rules. Dave
  16. Vodkaman

    1 lb ball

    Another problem that I had a year ago when I started fishing after a long absence. This also serves as a loose analogy. I was losing a lot of BIG fish on the strike. There are a lot of big fish, the pond record is 5.72Kg (12.5Lb) caught by me The problem was exasperated by the deep body profile of the bawal fish which provides resistance to the strike force. A smaller fish or a narrow body fish would be jerked through the water, effectively adding to the elasticity of the line and the 'give' of the rod. I was using 30Lb mono line and a carbon rod designed for big fish, so it was a tad stiff. Obviously I was hitting the fish too hard. I tried to correct this fault of mine, but in the heat of the moment instinct would take over and the line would snap. The analogy is that my strike was the equivalent of gravity only much higher. The fish was the weight, and the elasticity was a combination of the mono, rod flex and the jerk of the fish. The fish weight was fixed, I did not want to go higher in line thickness, I could not control the strike acceleration (gravity), so the only variable left was rod stiffness. So, I built a rod from a fiberglass blank intended for smaller fish. The rod flexed passed double, but I started catching more BIG fish. The problem was solved, and that's engineering Dave
  17. Vodkaman

    1 lb ball

    A very interesting question, but with no answer as there is an unknown. The weight dropping a distance influenced by gravity seems like a simple equation. In fact it is, BUT, it only gives you the energy (potential energy). The actual force experienced at the bottom of the drop is totally dependent on the elasticity of the line. Mono, having more 'give' will experience a lesser force than say braid or one of the modern thin lines that have less elasticity. The elasticity absorbs the energy generated by the free fall. A line made of elastic bands with huge elasticity will experience a much smaller 'load' than say a line with zero elasticity. I went through this exact process when I was designing a lure testing rig. I abandoned the drop test idea and went for a static load test. Dave
  18. I cut slots and drill all holes while the blank wood is still a rectangular block. This way it is easy to see if you are going wrong. I place a steel rule in the slot, this magnifies any errors. Not only is cutting easier, but if you totally screw up, then you haven't wasted any carving time. As for tools, I have no preferences, I usually use a band saw but it is out of commission. I can't find my dremel so that too is probably in storage, so at the moment, I am using a standard hacksaw. Dave
  19. From a non-plastic pouring engineer, the problem is always heat stress. A localized change in temperature that causes the glass to expand at different rates which causes stress cracks. But, I am pretty sure that you already know this as this problem is far from new. Even resting on a wood surface, a fairly good insulator, does not solve the problem, ref - Munkin's post. My suggestion would be to choose the best insulator possible. This will reduce the heat stress. A platter of plaster of Paris would be ideal for this purpose. Another fact that is demonstrated from the above posts, is that the life of the cups seems to be fairly constant. One cup breaks and shortly after the second cup breaks. So, if the first cup breaks then it is time to renew. If the cups break after say 6 years, then renew after 3 years, safer still, annually. Examine for micro cracks. Yes, they are very difficult to see. But, if you use a torch light, you will have more of a chance to see the refraction and reflected faults. Another idea is a 'ping' test. As cracks develop, I am sure (theory) that the sound of a metallic tap would change. Tap the new cups and remember the sound, or buy an extra for the occasional ping test comparison. My guess is that the sound would ring less or dull due to the micro cracks inhibiting the vibrations. I feel uncomfortable posting outside my experience, but it is all engineering at the end of the day. Dave
  20. Pete - Maybe 240 - 300 is a little optimistic. Five up/down cycles per second is going to set up a formidable vibration. A realistic possibility would be to set up an equal and opposite force to balance out the vibration, a bit like noise canceling technology, but, straight away the design more than doubles in complexity. If the vibration canceling worked, then 300 would be a low number. I wish I had an NC machine designer living around the corner. Dave
  21. The place to start is to make a list of the attributes that you consider desirable; what swimming action, narrow or wide, hunting or straight, depth, profile, length, weight, rattle and so on. Throwing distance is important too, especially for shallow swimmers. Consider the shop bought lures and how would you like to improve them. Dave
  22. Luredbaitz - I have just written a lengthy reply to the above post. I broke my rule of writing anything more than a paragraph in ‘Word’. Now I must try to remember what I wrote. I am not sure what ‘point’ you are referring to, my text or yours. The real point is; understand the basics of water movement and exercise your imagination. As for commercial lures, I cannot help you, as since I started this lure design journey, I have not purchased a single lure. I have not found luminescent paints locally, I would certainly be interested in experimenting with such. I have designed a flasher lure, but not built it as yet. I can only add that you should choose your colours according to the depth that you intend to fish; red, orange, yellow for shallow lures, blue, white for deep lures. There are many opinions on colours and form. My personal opinion is that it is all about action/vibration and colour and form are of little consequence. This is purely my own opinion and is not up for discussion. I loved the shrimp video, a perfect example of the application of imagination. I knew who the author was as soon as he spoke his first words as I am also from Liverpool, Paul Adams. I enjoyed your text and look forward to more feedback. Wishing you success. Dave
  23. Luredbaitz - I am so sorry about that. The message was to be quite the opposite, that you do not need to consider yourself 'smart' in order to come up with something original. Simply understanding what shapes the water is making when it passes a plate or surface is sufficient. Perhaps I should do one of those 'Ted-ed' lectures on YouTube Knife carving is an invaluable skill in this game. Welcome Dublin. Dave
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