Vodkaman

Yes, that would work. The important thing is that it has to be operated with one hand. A cake icing syringe would do it. Totally hands free would be an added bonus though. Stability is one of the most important aspects of the process. The mould should be fixed in such a way that it cannot accidently be pulled over by the pipe. Pushing is out of the question, as has been demonstrated on more than one recent thread. This would involve the hot plastic in the syringe. The beauty of the vac-venting system is that the hot plastic is poured in the normal way, except into an oversized sprue or funnel. It then disappears inside the mould and is not seen again until the mould is opened.

Yes, it seems that we have got copying successful commercial baits down to a TEE!

Of the above, the Tacoma is my favourite, purely as the collapse was all about vortices, my favourite subject! Come to think of it, I haven't mentioned vortices for quite a while. Nice to get the first one of the year out of the way. Vortex vortex VORTEX!!!

With the mould sealed correctly, the volume of the drawn air is the volume of the lure being cast. For the stuff that I have cast so far, this amounts to about 30cc. Weigh out an ounce of water in cup to get a feel for the amount of air involved. It is not possible to breath it in. It is more like blowing a kiss at your wrinkly grandma. Cured RTV is inert and cannot be any more of a problem than keeping it in the same room all day. The whole issue can be avoided with the use of a vacuum pump. I am estimating that a fish tank pump would be strong enough to do the job. It is more important to make the suction pipe a long one and made of clear plastic. So far, I have never managed to draw the plastic out of the mould, but why take the chance. Another safeguard for both the above hazards, would be to introduce a DRY reservoir half way up the pipe. This could be a hard plastic bottle, with one pipe in and a separate pipe out. Thanks for your concern Bruce and I am looking for a pump For testing, also I am only doing a few test pours for TU, once the pour works, I move on to the next project, which is probably back to hardbait lips.

Bruce is right. If it is your first, I would not paint this one, but use it for testing. If you have invested a huge amount of time, you might want to put this one in the draw for now and make another one for testing. Only needs to be roughly finished. You will need to experiment with eye location, in addition to Bruces suggestion of ballast location. Test it out, write information down about what you try, any measurement changes etc. Any problems or queries, come back and post them. You have chosen a difficult lure to start with as its best swimming setup is very close to instability. But ask the right questions, the members can help you get it working.

Many years ago, I used to home brew from the basic ingredients. I tried kits, but like lures, more satisfaction was to be had from building it myself. Tedious labour, mashing at 150 deg for four hours and then simmering for another 90 minutes. I wish you good luck and prosperity with your venture. Don't forget, 'drinking on the rocks can seriously damage your health!'

You would think that with todays mathematical and engineering knowledge, computer stress analysis and simulations, that designing bridges would be childs play. Not so. Just a few years ago, a new bridge over the Thames, in London, had to be closed very shortly after the ceremonial opening. The bridge had a very slight sway. This caused the people to walk in step with the movement, also it is a natural instinct for humans to walk in step with each other. It just happened to be that the frequency of this step pace matched the resonent frequency of the bridge and the sway was dangerously magnified. How embarrassing for the designers!!!!

Re-visiting this thread after so long, does put a fresh perspective on things. Upon re-reading fishnfool's post, it struck me immediately, the same as Hughesy, that the changes in the lure are causing the contradiction. In my mind I was keeping the lure constant and only considering the water density. Respect to Fishnfool, no fool it seems!

You can see from the legs, that some are longer than others, so the limit is being approached. RTV is a very good insulator and maybe the plastic gets to flow a tad further because of that fact. Pre-heating the aluminum would help, but I'm sure you tried that. Another feature of my mould is the size of the venting. This greatly increases the force on the plastic. The third important point is the sealing of the mould. If you block the sprue with your finger, you should not be able to draw any air through the suction pipe. Any leakage would reduce the drawing force on the plastic. Try a coating of pam oil on the contact surfaces. Personally, anything but the very simplest of pours, will be vacu-vented in my pouring studio.

Sorry Bruce, English humour.

Clemmy, I think we are missing the point here. Could you post a pic.

Semidry - adjective - wet behind the ears!

How to mould 3D legs with a 2 part mould This thread is in response to the thread linked below. Hopefully, it will open up the possibilities for new designs, such as octopus, squid etc or even abstract designs that were not within the realms of feasibility before without expensive equipment. this is the lure posted by DelW in the ‘IKA like pours’ thread. http://www.tackleunderground.com/forum/showthread.php?t=11261 this shows the legs emerging from the body radially. The only way to mould these in a conventional mould would be parallel to each other in the plane of the mould joint face. This would be aesthetically unacceptable. Materials ¾ inch dia dowel. Packet of sate sticks Body master RTV RTV is used as the mould manufacture includes under cuts. However, the design can be adapted to carry the undercuts on the slug. This is more work intensive, so for this experiment I chose to cast the legs into the mould. To create the leg master, the dowel and satay sticks are cut to the length of leg required. Glue the satay sticks around the outside of the dowel. I managed 14 legs with a smaller diameter, but I did lose some definition between the legs, resulting in some trimming. The lesson is, don’t put the legs too close together, I would say minimum 1/8th, 3/16th would be better. The plan was to grind flats onto the satay sticks, but this was found to be very tedious and subsequently not necessary. I used instant super glue for this operation. The leg master must be sealed, epoxy or resin will do the job. A good coating of Pam oil or something similar will be required to stop the RTV from binding. Set the master up against the leg pattern and create your 2 part mould in the usual way. Personally, I use a split master technique, but each to his own. The slug insert is another length of the same dowel, cut a few millimeters shorter than the leg master and seal. The plain slug cylinder is inserted into the mould. Make sure a gap is left at the top for the plastic to reach the legs. The mould is now ready for the pour. Whether you can get that many legs to pour using the regular gravity method, I don’t know. I did not try, I went straight in with the vacu-venting method. This is my layout ready for pouring the RTV. If PoP is to be used as the mould material, then the undercut of the satay sticks has to be eliminated. This is done by casting the plain dowel cylinder into the mould and cutting the legs into the slug. This method would be the solution should the mould be made in aluminum. However, the long thin legs would not lend themselves readily to the heat transfer characteristics of the aluminum and an injection or vacuum method would probably have to be employed. Del would be the man to advise on this possibility. Below is a photo of the resulting lure. Scruffy? Yes, that is down to my lowly position on the learning curve, but proof enough that the technique works. By choosing more accurate and stable materials, such as a turned master, plastic rod or tube to replace the satay sticks, decent RTV, attention to detail and precise workmanship, it will be possible to produce a quality casting with zero flash. This test pour also demonstrates further the effectiveness of the vacu-venting process. http://www.tackleunderground.com/forum/showthread.php?t=11056&page=2&highlight=vacu-venting I would appreciate some feedback on this thread and the vacu-venting thread, questions, reservations, like it, hate it etc.

Silence is golden.

The concave back and deeply convex belly will act together to rotate the body downwards. The result being that the lure will swim shallower than the same bait with a regular configuration. Similar to an aerofoil section up-side-down.

Liquid latex. I was thinking about that application. While deciding whether to post it or not, I saw zman's post. It sounds like the same stuff.

The Falkirk wheel. Yes, I posted it, an awesome piece of modern engineering. But you have to respect the guys that built the old masters a hundred, even two hundred years ago. Their work looked good too. This is where I fished every night after work when I was in Sweden. Alvsborg bridge, Goteborg. Just look at that geometry!

To dampen some of the action, try adding some weight to the rear. Temporarily tape it on first and test it out. A photo or two would help.

This is a project that has been in my book of 'things to do one day', for quite a while. 3D legs from a 2 piece mould. I brought it forward because the subject was touched on a few days ago in a thread called, 'IKA like pours'. I have posted it separately because it has much wider applications than just copying IKA's.

Their have been a few good posts on cutters, you might want to try a search if you have not already.

The pic with the ruler in it was blurred. The core body length is 100mm (4 inches) as are the longest legs. I made it as an experiment to see how far I could push the boundaries and still get a good casting. This is probably getting close to the limit.

Grant. Many thanks for filling in the profile, good man. I just wish everyone would. Many people are overly paranoid. When you get started with the class, take lots of photo's of the proceedings and the results and start a new thread. This could start a new trend that can only be good for the sport. You could even take the class through the whole process, each student could design a lure, mould it, pour it, fish it and if they catch anything, they will be hooked for life!

That is great news, congratulations. Now, as you are new to pouring, you need to research every aspect of the safety. The members here are very pro safety. so, a search or two should get you the information. At the top of the plastic forum page is an excellent starting place, 'don'ts for newbies', three pages of valuable tips. I'm sure a few extra tips will be forthcomming on this thread too.

Grant. From your TU name, I am assuming that you are in the UK, why not take the time to fill in your profile, it will help people understand your situation better. I think it is really cool idea to make lures with kids. It would set them off in the right direction regards safety procedures. Your problem is going to be the education authority. They are unlikely to grant you permission, but you never know, their might be an angler on the board. Even before they grant permission, it will have to be declared to the schools insurance companies. Do NOT proceed without permission, you will open yourself to all kinds of problems should something bad happen. I sincerely hope that you do get the go ahead on this one, as some of the students will possibly take up pouring on their own and will have missed out on the safety aspects of the persuit. Good luck.

Nathan, sorry to interfere. I PM'd Rossrods and said that this time, it would probably be best to leave it here now to save confusion. It is actually worth a thread of its own. Ironically, another thread has been started on basically the same question. http://www.tackleunderground.com/forum/showthread.php?t=11300 I assumed that this was the new thread, but did not check the author.