Vodkaman

I think that it is possible. The problem I presume to be the plastic splitting if the fin was too deep. This could be solved by making a retractable fin. When the tube is ready to be removed, apply thumb pressure to the hinged fin to rotate it back into a slot in the rod. It will complicate the rod build, but you only have to build it once to make thousands of finned tubes. I have the design in my head.

For each product you will likely find a web site that outlines all the hazzards and symptoms. Look up the product names and see if they tie in. I'm real sorry to hear about your health problems. You are right, a 24 year old should not be suffering from such symptoms and would strongly suspect the chemicals that you have been playing with. Let us know what you find and good luck.

Is there a density or specific gravity figure quoted on the plastic container? If not, it will be possible to calculate it. Cast the plastic into a cube or a shape that can easily be measured. First, calculate the volume, length x breadth x width measured in centimeters. Measure the weight in grams. density is measured in grams per centimeter cubed (g/cm3). Divide the measured weight by the volume and that gives the density. It has to be less than one to confirm that it floats. To calculate how many cm3 it would require to support 1 gram of weight:: Vol cm3 = 1 / ( 1 / density – 1) Do not be put off by this formula, simply type into your calculator as follows: 1 / density – 1 = write this number down or put it in the memory. Cancel. 1 / memory = answer in cm3. To convert this number to cubic inches, multiply the answer by 0.061. If this is no clearer than mud, PM me the density.

And there's me thinking it was something to do with alchemy!

It could be injected with a hypodermic needle, before the plastic solidifies. Should not be too dificult to set up. It will all be in the timing.

Dean, thanks, that’s the basic idea. Hazmail, you also have the basic idea, except the forces on the lip are higher because it is a flat plate. example, imagine you want to move a 1 inch plate through the water as easily as possible. You would add a fairing around it shaped like a wing section or torpedo. The shape would slip through the water with reduced resistance. That is what is happening as the water is passing over the body. So for the body to balance the lip, the body area will be greater. The ratio between the two could be calculated, but is way beyond my capabilities. An eyeballed ratio of about 2:1, but don't quote me. It would be nice if it was a constant ratio, but it will vary with changes in body shape. Skeeter Jones. There is nothing to measure, the line of instability is an imaginary line. If the ballast is moved beyond this line, the bait becomes unstable. The line will be a different distance for each bait geometry. The important thing is to understand that it is there. So what was the point of the thread? How can the theory be used? The document tries to explain what causes the death roll instability, were the lure rolls too far and cannot recover and spirals out of control. In the case of deep divers, as depicted in diagram 8. to correct the instability, the ballast must be mover forward of the line of instability. This can be achieved in a number of ways. A) physically move the ballast forward. move the tow eye forward. C) trim the lip shorter. D) shorten the body from the tail. Selections B, C and D all alter the lip/body balance and cause the dive angle and the tow line angle to be reduced. This in turn moves the line of instability further aft as it is parallel to the tow line. On a steep lipped, shallow diver, see diagram 7. the weight is shown sitting on the tow line. This unstable condition will give the most action, it may or may not lose control. If it does, a slight adjustment of the ballast fore or aft would solve the problem, also B,C and D would achieve the same. So, is that the full death roll story? I doubt it. Does the theory work? Yes, in my experiments so far. Is the theory correct? I can’t say for sure. Should I have released the document? If I didn’t release it, I wouldn’t get feed back. If I am definitely wrong, someone out there will correct me and because it seems to work, it cannot do any real harm. Any experiences or observations around this subject will be gratefully received, if you make a lure that death rolls, DON’T throw it away. Tell me about it, photo’s would help, with a description of ballast location etc, either by PM or post.

The best that I can come up with, is to drill a small diameter hole, just above the dip line. Thread some cotton (or similar stronger thread) through the hole. Anchor with a knot to stop it pulling right through. Arrange the feathers around the tube, hold them in place with finger and thumb of one hand. Wind the thread around the feathers a few times and then wind it up the rod. Either hold the thread taught or clamp it off with some tape, or cut a VEE slot to jam the thread in. This would hold the feathers in place, but they may still spay out. A solution to the splay might be to add a slight taper to the rod. Alternatively, a few turns of regular cotton to gather the splayed ends, a half hitch and trim. This cotton would be permanently inside the plastic. It could work, could be worth a try.

Works for me.

Your right, on reflection, it is more like two hundred. From last october through to June this year. It occupied my spare time during the Swedish winter. They were all prototypes, testing diferent lips, ballast positions and design ideas. Some nights I might built five or six, others none. My standard prototype build takes less than 30 minutes, that is from getting my tools out to dipping the sealed (5 min epoxy) lure in the water. I believe the question arose from a PM that I sent to Swede, in which I outlined my lure building experience. I believe that Swede asked the wrong question, he should have asked, 'how many fish have my lures caught'? The answer would be zero, as I have never actually fished one. I have made it my hobby to firstly, answer the question, 'how does it work'. Secondly, to develope a lure design diferent to everyone elses. It must look different and swim different. It would probably help if it caught a few fish too, that test will come soon, as will learning to paint. If you conclude that my actual lack of experience in catching fish disqualifies me from having anything to say on this subject, then you need not read my threads. But consider this, I have probably done more testing of different configurations of lures than most. The research will continue, the theories may be modified, corrected etc, but I am confident that I will get there in the end. Thanks for all the input from all the posts on TU, a true learning experience.

Skeeter jones. In diagram 7, the point was that if the lure is built in such a way that the tow line direction was in line with the ballast then instability would or could occur. Because the ballast no longer has any momentum (force x distance), it no longer has any stabilizing effect. The minutest asymmetry of the lip would cause it to pull one side more than the other and with no damping, would very quickly spiral out of control. In diagram 8, the line of instability represents the perpendicular distance of the ballast from the tow line, as moments are actually force x perpendicular distance. When the ballast sits on this line, its moment equals the forces on the lip, a bit like opposite balance weights on a wheel. At this point, the lure is at the point of instability. The slightest fault on the lip would tip it over. If the weight was moved further rearwards, thus moving the ballast beyond this line, the lure spirals and death roll occurs. I arrived at these conclusions by varying the position of the ballast from the front to the rear of the body on the same lure. A ballast position is reached were the instability starts. This is my interpretation of what is happening. Regarding the two lines question. You are correct, the line has been missed out. The line should be parallel to the tow line, the same as in diagram 8. Apologies for the confusion. Sagacious, you are indeed correct. You have corrected a huge hole in my assumptions. In fact it has been a point that has severely hampered me in all the time that I have been doing this study into how the lure works. Vortices and any other flow effects are reliant on the fluid being compressible, so I thank you, my job now becomes that much easier. For the last hour I have been trying to think where did that incorrect assumption come from as I studied fluid dynamics for five years, while completing my HND in aerodynamics. The only thing that I can come up with is that every question on fluids on the course started, ‘an incompressible fluid, of density blah blah, traveling at blah blah’. I guess the incompressible part stuck in my head. You got me, your not the first and I’m SURE that you won’t be the last, thanks again. Lapala. I would have to agree with you except I know exactly what I wanted to say, but on re-reading the article, I realize that I probably caused more confusion than clarification. This subject is probably one of the most difficult to understand. If I were to consider every single component and take into account their effect on the death roll, the problem would be too great and would likely give it up. The idea is to establish the major factors and analyze the effect of those factors in isolation, in establishing the cause of death roll. I have done the same with each of the aspects of a lures operation, in the hope that all these individual snippets of theories will eventually pull together and allow me to design the lure that I want and hopefully help a few others on the way. I feel that I am closer to getting the big picture, but how close, I cannot answer. I would certainly accept alternative ideas on the death roll question. Although I think that the theory is plausible, I have to admit that I am not 100% confident. I will certainly be re-visiting the subject in the future (groan!!), when I think of a way of explaining it more clearly. I will take on board the vector idea and give it some thought.

About Four hundred or so. WHY?

This happened to we a while back. Make sure you click the 'remember me' box and the problem, if it was the same as mine, will go away. I mostly have huge problems with the PM system, but only on my works system. Sometimes I type a medium length text, press send it and the system displays a web page problem. The big problem is when I click 'back arrow' to return, all the text that I typed is lost. Unfortunately, there is no copy function under the right button context menu. If I start to et carried away typing (as I often do!), I select the text and drag it to a word document, to safe guard my work. Any solutions?

Chartreuse, ah yes, the perfect birthday present!

The problem is to create a stable, distortion free mould, using as little of the expensive RTV as possible. My solution is to thick skim the pattern in the lego box, as outlined by Husky. After the RTV has set, top up the mould box with PoP. The PoP former holds the shape for the casting process. The RTV thick skin can be easily separated from the PoP former, for easy de-molding of the casting. The PoP former is sealed with 50/50 PVA and water. This will prevent dust contamination and help prevent chipping, although small chips in the former will not affect the function. A quick, cheap and cheerful solution. Would it work?

Wiggle, waggle, wobble, that is precisely how I percieve the intended movement descriptions. This is were so much confusion is caused when dealing with this subject. Many people refer to wobble as a side-to-side movement. As to the rest of your post, I am forced to retreat and think some more. I particularly like the cone example. I'm off to bed now, I am going to have nightmares about killer cones! PS. Saved by the edit function! I totally agree. It is all about what is happening behind the lip. You could argue that, when swimming, you may think that you are 'pulling' your self through the water, when in fact, you are being 'pulled' through the water by the low pressure created on the back of your hand. It's a heavy thought and I have not convinced myself of the idea yet, but it has merit. The cone, flat first, the vortex has less room to do its work. PPS. Got out of bed to write this! Regarding the pressure statement, I have two arguements against this idea. Firstly, if the pressure had the effect of reducing the action, that would imply energy comming into play. Therefore, the angler would have to pull harder, this extra effort would be collected by the lip and would cancel out the resistance on the body. Secondly, because water is incompressible, the water properties are no diferent than at the surface. Example, it is no more dificult for a deep sea diver to move around at a depth of 1000 ft than if he was working in the deep end of a swimming pool.

Clemmy, would appreciate some clarification of your statements regarding the trailing edge shape and the hydrostatic pressure. Hazmail, I assume the concave face forward gave the wide action. Do people (or more correctly, fish) prefer a wider or narrow action? I expect both each have their good days.

Thanks Rofish and BobP for your contributions to this post. As most of you will already know, I am writing this from an engineering point of view rather than from hard earned experience. I wrote the document in order to test out the applied theories and logic against responses from experience. Unless the engineering theories can match the experience then the engineering principles have been misinterpreted and I have to re-think. Taking the points raised in the above replies: Waggle. There is always going to be a terminology problem until TU introduces a glossary of terms. You are correct, I was referring to side movement. In engineering terms it would be called yaw, rotation about the Z axis. As a new member, I struggled for months with many of the words used on this site, I really could have used a TU dictionary. Lip shape. This is a difficult variable to account for. A narrow lip can be compared with a wide lip and sweeping engineering statements made with confidence. But shape affects many things. The width of the lip varies, the direction of the forces on the lip vary, the amount of water that hits the body varies. The only way anything positive or definitive could come from an engineering point of view would be by filming in a fluids lab test tank. I would love to get involved with that idea, if I was sixteen again, I would be heading for a fluids course at college, lure design would make a perfect thesis subject. At the moment the answers to this enigma lie with experience, to which I humbly bow. Same lip on different bodies. The tight or wide action is never going to be totally dependant on the lip. The lip is the engine for the action, everything else on the lure, right down to the Devcon only serves to dampen the action. It is just a question of degrees. Stick a sports car engine in a bread van and the action will be dampened somewhat. Split ballast. The points made regarding the inertia of the ballast are of course true. It is hard to start the boat moving and equally difficult to stop it. But the lip engine moves on. The rate of oscillation generated by the lip is totally unaffected by what is happening behind it. The only factors that affect the frequency are lip width and velocity. As inertia increases, the lure has more difficulty in moving before it is forced to change direction. Increased inertia definitely dampens the amplitude or width of the action. Tow eye location. I have save the most difficult until last. The eye location on the lure determines the angle that the lure swims. The forces below the eye generated by the water flow on the lip rotates the body nose down. The forces generated by the water flow on the body rotates the lure nose up. When the forces above and below are equal, the angle that the lure sits determines the dive depth. This up/down rotation or pitch, is centered around the eye. If the eye is positioned on the lip, as on a deep diving lure, the portion of the lip behind the eye is acting with the body. In theory, the same could be achieved by moving the eye back onto the body and reducing the lip size. This is probably contentious, but that is what discussion is all about. The yaw, caused by the side forces from the lip, is centered around the centre of gravity and NOT the eye. Therefore, it does not matter where the eye is, it will not affect the yaw action. What DOES affect the action, is the angle of the lip at the balanced attitude. If the eye is moved forward, the forces on the body increase and the lure rotates nose up until a balance is once again achieved. The lip now presents less area and less vortex creating side length to the flow direction, thus less power is generated and consequently, less action. The maximum action is generated when the maximum lip is presented to the flow, this occurs when the lip is perpendicular to the flow. This situation is also close to instability, but that is another discussion. Another factor that affects the action is the distance between the lip forces and the CoG. Applying the lever principle, the longer the distance, the wider the action. Inertial forces will come in to play though. There will be an optimum position for the ballast for the widest action which would be about half way along the body. This is convenient, as that is roughly where we would want to put it in order to statically balance the lure.

I always have to ask myself have I been too harsh, as I know I have a tendancy to shoot from the hip. I have even made a personal rule, that when I feel angry or hard done by, I have to wait 24 hours before typing a response. I have thought hard on this one. I have read the back posts and have to agree with you all, that no real contributions were forth comming, mostly he was touting for work etc. Their is nothing really ground breaking about painting lures, nothing that hasn't been done before. All we wanted to know was what method he used or what paint he applied, what did he use for the scale pattern etc. He would have increased the respect that he already had from the TU members and probably sold even more lures. I am really baffled why he should take umbrage at our reaction to such an un-cooperative attitude. If you are reading Mr K. Their is really no point in leaving, that achieves nothing. All we ask is you try and get with the program and contribute. It is quite painless and will not damage your business, in fact business would probably increase as we all prefer to buy from the good guys. I can't speak for everyone, but I have found that most of the guys here are quite forgiving. So I suggest that you swallow your pride and get back on the horse and contribute.

So what solution did you use in the end?

I'm kicking myself. I didn't go past page 5 on the search string. The answer was on page 6!! AAAAARRHHHH!!!!

Yes, I got one earlier on, no one noticed because I had hardly pressed the go button and KC posted the answer! What is the point of easy, Bring it on.

I'm beaten, I know the name is right but can't find anything else. I'm up for another from KC if everyone else is done.

It is sad and too bad. He may have gone home, but we still have the ball. I think that you were right to raise the issue Mike and I thought that you did it nicely, not in a disrespectful way.

Has anyone had eny experience using Gelflex for making moulds? It is a re-meltable plastic available in two hardness's. It is soft enough for undercuts and good for a couple of hundred castings off simple mould shapes. I would appreciate any feedback.

This problem occured a while back. I thought the best idea that came from that post was to try and contact the original pourer and ask him. Because he is no longer in business, he probably won't have any objections to sharing his recipe. Has to be worth a try.