Edited by jamie, 22 January 2009 - 07:52 PM.
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Need help with an idea for a ratttle trap
40 replies to this topic
Posted 22 January 2009 - 07:49 PM
Well what im trying to do is make vent holes in a rattle bait. In southern musky fishing in late Febuary and early March in the back a coves rattle baits are the bait of choice. Im going to for the first time try alumilite and want to try something a little different. In the bait I want to make vent holes for water to flow through. In the head of this bait I want water to flow into a small hole and exit out the side of the bait, around the gill area. I could drill every bait out but im wanting to make it molded into the bait to save time and to make every bait the same. Im looking to make a different sound hopfully, along with the differnt types of rattle options that Im going to try for this bait.Im wanting to try some differnt things out in time so that I can give the guides on Cave Run some baits to test for me. So what I need is how do I mold this idea into a blank that I have carved out Thanks guys
Edited by jamie, 22 January 2009 - 07:52 PM.
Posted 22 January 2009 - 09:22 PM
In moulding jargon, what you are after is called a 'core', it is a seperate moulding (positive) of the void you require, which is then fixed in the primary mould cavity. These cores have to be made out of something that is dispensible/removable and in days past sand was used in most moulds, but today they probably use styrene or something. For your purposes, I think I would use bees wax, so you will have to determine the shape/area of this 'hollow' and make a pattern of the void required- I would not bother with all these fancy moulding materials, just use hobby clay (plasterscene), soften it up and shape it to what you need and then freeze it- remove it from the freezer, and then make a positive (2 piece mould) of it with whatever medium you prefer, let it set, remove the hobby clay - start pouring, make more 'cores' than you think you will need, then fix one in place in the main mould (you will have to work out how you are going to fix it in the main cavity), the master mould must be jigged to fit each new 'Core' back into precisely the same place every time you want to cast a lure, this way every lure will be the same (same as casting a hook into a jig). I say use wax because when the lure is cast and is removed from the mould, this 'core' will be stuck in there, so you will have to melt it out leaving your sound chamber. Whatever material you use for this 'core' should be disolvable/removable weather you dig it out or dissolve/melt it, so maybe you can come up with something!! sugar dissolves in water??. The best of all if you can shape it would be styrene foam, just pour petrol on it (or spray 'Carby Clean') an it dissappears. For a more hi/tech up to date material, 'Reeves' (George) 'dlaery' (David) may be able to help, they are all over these new silicones etc. Sounds easy!!, I just finished a swimbait and I thought that was hard, phew. pete
Edited by hazmail, 22 January 2009 - 09:27 PM.
Posted 22 January 2009 - 10:24 PM
Pete i have the idea of making molds its how do I intergrate the idea of the vents into the bait. Ive done the research on molds and have the knowledge for that its how do I get the vent hole molded into the bait. Do I run heavy guage wire out of the bait where I want the holes to be and mold the bait like you would when you cast lead egg sinkers with a removable pin to give you the hollow effect? Its hard to understand what i need done and I wish that I could explain it a little better.
Posted 23 January 2009 - 12:35 AM
Sorry, I thought you wanted a chamber with small holes at either end, I'm doing this a bit lately???. If you want a small hole in and out I think a piece of wire/rod through the mould in the appropiate spot and then just pull it out when the 'Feather Lite' is set. I know nothing about this stuff, but I suspect you will need some sort of release agent on the wire, and there are plenty of 'plastics' guys who make moulds all the time and should be able to advise you on that.
What's a small hole anyway????
Posted 23 January 2009 - 10:34 AM
what Im doing is trying to get a sound effect from the the water going in the intake and exit the side port holes in the gill area of the bait. As far as what is a size holes Im thinking of a larger intake hole and narrow down the exit holes and try to get a water nozzle effect. Hopfully this will a different sound added to the differnt rattle options I have instore for this bait.Rattle baits are a big thing here for that time of year and I wanted to take this bait alittle outside of the box and make it different from the rest.
Posted 23 January 2009 - 10:42 AM
It might be easier to mold in the larger hole, from front to back, and then drill the smaller, side to side hole afterward.
That should make the operation simpler.
Be careful that whatever you use can be cleaned out completely, without leaving a residue that might react with you paint and top coat. That goes for the release agent and disolving chemicals, too.
Posted 23 January 2009 - 11:12 AM
Mark the larger hole doesnt run from front to back, the hole should enter through the head area and never go any farther than the gill area then it should vent out to the sides of the bait around the gill area. drilling is an option I thought about but wanted to see if I could mold the bait this way first so that I would have an exact bait every time. drilling leaves room for error and and if you dont line the the intake hole and exit hole up right water will never flow through it.
Posted 23 January 2009 - 11:20 AM
I said front to back just to show the direction of the hole.
As I understand it, you want a T shaped void, with the leg of the T, the larger hole, starting at the front of the lure and moving back to the gill area, and the smaller hole, which forms the top of the T, going side to side.
I would think that aligning the cross hole would be easy, once you had the front hole in place. If I were doing it, I'd stick a long dowel into the front hole, to show it's orientation, and then, using the direction of the dowel as a guide, move to the drill press and drill the smaller, side to side hole.
If you're going to do a lot of them, you can make a jig that orients the bait and drill press automatically, so the holes always line up.
I offered this as an option, in case molding in a T section was too difficult.
I thought making just the front hole in the mold would be simpler, and you could use a slightly tapered dowel for the front hole in the mold, which would make removal easier.
But, then again, what do I know?
Posted 23 January 2009 - 11:56 AM
I was thinking the same thing as you mark but I was trying to get around the drilling. I will go with this idea to see how it goes and thanks mark and pete for your input.
Posted 23 January 2009 - 12:03 PM
If you are going for a 'T' arrangement, then inserts will work very well. The nose insert will be say 6mm dia aly bar. Drilled 3mm dia to accept a short length of welding rod.
This would give three points of contact in the mold. After curing, the 3mm is withdrawn first. This will release the 6mm rod. Just grease the rods before closing the mold and pouring.
This will obviously give exit vents top and bottom. But I see no reason not to go side to side, if you prefer.
Edited by Vodkaman, 23 January 2009 - 12:05 PM.
Posted 11 March 2009 - 08:14 AM
This sounds like an interesting option for a bait. Any progress?
Just thinking, with a bigger entrance oriface, and smaller exit holes, wouldn't the bait have a lot of resistance in the water (unless the exit holes add up to the volume size of the entrance)?
Posted 11 March 2009 - 05:11 PM
Still working on this ,I have been working my off at work and what time I do get Ive been working on some gliders. I have the proto type made just need to mold them to get started. The larger hole that I was talking about is not as big as one would think, but big enough for water to pass through. I hope to make some progress on this this weekend if the good lord is willing.Thanks for the interest and I will post some responses when finished.
Posted 12 March 2009 - 08:35 PM
Well got working on this again and think that im going to have to drill the holes after I pour the bait instead of molding them in. I drilled some holes for the exit and inserted some ss wire and they all intersect along a predrilled hole that runs from the head of the bait and angled down torwards the tail a bit about half way through the head. The problem that im seeing is the angle of the pins. They are in all the directions and I dont think that I would be able to release the bait from the mold due to the angles of the pins. I wanted to see what the mold experts opinions are , can I or drill after the fact. I placed these pins so you can see the angles Im talking about. In theory the water should pass through the entrance hole in the head of the bait and exit out through the holes along the jaw of the bait and hopfully make a squeal. Please excuse the roughness of the bait it needs filler sanded and a coat of d2 before molding. I need some opinions before I fill the holes Ive drilled and coat with clear.
Posted 12 March 2009 - 08:57 PM
I still think it is possible to mold the pins in. As long as the pins extend out past the surface of the mold.
Grease the pins with wax and they should pull out.
Posted 12 March 2009 - 09:20 PM
Let me ask another question , do you think this concept will work?
Posted 12 March 2009 - 10:24 PM
I don't think anyone can answer that question, you are breaking new ground.
I say go for it and find the answer. It is all good experience even if it does not work. I am hopeful.
Posted 12 March 2009 - 10:30 PM
I imagined the direction of the venting holes to go towards your hand (in the picture), assuming you were holding the bait at the back.
Posted 12 March 2009 - 11:57 PM
Just remember Jamie, the two exit holes should be apx 3/4 the size of the one entrance hole if you want the incoming volume to pass through - i.e, a hole twice the size has four times the area/volume.pete
Posted 13 March 2009 - 04:21 AM
I think this concept will work, having the holes on the side like that, low pressure passing over the holes will pull water through the front or main hole. Think of the air conditioning in a car, when the vents are closed, you get average air flow, but once you crack open the sun roof, it feels like air is shooting out at you.
Oh BTW, where is your ballast? i'm having trouble locating it in the rattle trap i am casting, but most agreed that it should be low and towards the nose
Posted 13 March 2009 - 06:16 AM
Jaime, what you want to do definitely needs a multi-part mold. A minimum of 3 part should work. Part one would be the head (or just a cap) with a formed metal rod that you can pull out to form the vents; then a 2 half molds for the body.
As to your venting design there are quite a number of top water lures that has incorporated vent holes that I know of which you can check out for some guide.
One of the 1st lures that I know of with this design is the [FONT=ＭＳ Ｐゴシック][FONT=Arial]HMNG Bubble Popper 2 Duct. [/FONT][FONT=Arial]Daiwa came out with another much later called Saltiga Pencil with a gill vent. Patended Open Gill design is what they call it (US Pat No. 5276992) In btw there are a few more designs that has this venting. I think Dean or KcDano could give us even older examples.
But theorathically what you want to be looking at are cavitation effect or check out a water aspirator design. All these effect occurs at higher speeds though. You can make it work in a lure which has a large inlet with a "tunnel" to force the water out thru very small vent producing a high speed water jet in the outlet. The design of the tunnel is the key to make it work. Inlet position is important too so the lure action is retained while promoting the path of water that needs to be channeled into your "aspirator" in the lure.[/FONT][/FONT]