Vodkaman Posted November 11, 2008 Report Share Posted November 11, 2008 (edited) Thanks guys. Often starting out, without no prior knowledge of how things are supposed to be done, can lead to new ideas. Here is the link to vacu-venting. Post 4 shows the incomplete spider casting. Post 13 gives the explanation of vacu-venting. Post 15 shows the successful pour and also the RTV mold with the venting. http://www.tackleunderground.com/forum/soft-plastics/11056-hairy-worm.html As far as I know, only one member has taken up the idea and he has had success. If you want to discuss it further, I suggest a new thread would be in order, as it is off topic in this thread. Dave Post script. Robalo01, yes, good idea. It is the depth of the plastic that gives the head of pressure and not the volume of plastic. Edited November 11, 2008 by Vodkaman ps Quote Link to comment Share on other sites More sharing options...
RiverMan Posted November 15, 2008 Report Share Posted November 15, 2008 Jim, That is a very clever way of venting your grub molds. I have vented my plaster molds in the past with just one vent at the end but I think your design would be a great improvement. Thank you. Jed V. Quote Link to comment Share on other sites More sharing options...
GB GONE Posted December 3, 2008 Report Share Posted December 3, 2008 Sorry for the great delay. Family matters took over on this project. Happy to say, as you can see the results below, mold was a complete success. I did not even drill the hole in the center of the curl tail as planned and the grub plus tail pours perfectly every time. As seen in the photos below, the tail is nice and thin. The action from the resulting grub is excellent! That means another $50 from my buddy!!! Just on time for the holidays!! Jim Quote Link to comment Share on other sites More sharing options...
saint308 Posted December 7, 2008 Report Share Posted December 7, 2008 What's up folks. It has been a really long time since I have posted here. We just had our first baby so pouring has been on the back burner for me. I have read this thread and found it very interesting. I may try to learn how to make my own molds to play around with. I also want to say thanks to Jim for all of his work and willingness to share secrets. For those that don't know he is very good at this stuff and a very good source of info. Saint. Quote Link to comment Share on other sites More sharing options...
alsworms Posted December 7, 2008 Report Share Posted December 7, 2008 What's up folks. It has been a really long time since I have posted here. We just had our first baby so pouring has been on the back burner for me. I have read this thread and found it very interesting. I may try to learn how to make my own molds to play around with. I also want to say thanks to Jim for all of his work and willingness to share secrets. For those that don't know he is very good at this stuff and a very good source of info. Saint. Great to hear from you Saint, and Congrats on the new baby! Quote Link to comment Share on other sites More sharing options...
saint308 Posted December 7, 2008 Report Share Posted December 7, 2008 Thank you very much. It is great to be back. Saint. Quote Link to comment Share on other sites More sharing options...
GB GONE Posted December 8, 2008 Report Share Posted December 8, 2008 Glad to hear mom, baby and dad are doing good! Life is going to be changing bid time now!!! I learned way more from this site and continue to learn from the ideas posted up here than I could ever hope to give back Saint. Glad to see you back!!! Jim Quote Link to comment Share on other sites More sharing options...
rsinyard Posted December 8, 2008 Report Share Posted December 8, 2008 Sorry for the great delay. Family matters took over on this project. Happy to say, as you can see the results below, mold was a complete success. I did not even drill the hole in the center of the curl tail as planned and the grub plus tail pours perfectly every time. As seen in the photos below, the tail is nice and thin. The action from the resulting grub is excellent! That means another $50 from my buddy!!! Just on time for the holidays!! Jim This brings up the question I asked about Del's 10" curly tail mold a while back. Since this is a proven method for plaster molds, what is your thoughts on using this method on aluminum molds. Would this method work on the 10" curly tail aluminum mold so that you didn't have to pour the tail before putting the mold together? Quote Link to comment Share on other sites More sharing options...
GB GONE Posted December 8, 2008 Report Share Posted December 8, 2008 Sure Del will chime in as aluminum is his expertise. My opinion is that the aluminum cools the plastic so fast that the tail will not pour unless poured first. Aluminum will take the heat from the plastic but the plaster is an insulator and therefore holds the heat keeping the plastic liquid longer. I have thought of an idea that will allow for the pouring of long tails and a long bait body. I am testing the idea on a 2 piece snake mold right now (Similar to Mann's hardnose snake bait). Should have results before the end of the week. The body is about 6" long and the ribbon tail is at least 4 inches long and thin. Idea is so simple that I am sure others have thought of it and used it before. Initial testing has been all positive so I am highly (90+%) confident that the molds and baits will work as planned. The idea should be able to be used on aluminum molds as well. Pictures and thoughts to follow. Jim Quote Link to comment Share on other sites More sharing options...
Delw Posted December 8, 2008 Report Share Posted December 8, 2008 Sure Del will chime in as aluminum is his expertise. My opinion is that the aluminum cools the plastic so fast that the tail will not pour unless poured first.Aluminum will take the heat from the plastic but the plaster is an insulator and therefore holds the heat keeping the plastic liquid longer. Jim Thats Exactly it Jim, Alum cools off to fast for very thin and even curl tails to get in one pour. Plus alum molds are as smooth and slippery as silicon. If you have the molds pretty hot some times they do work on some molds but not all. What is weird I have a U shaped curl tail mold that pours just fine in one shot but one with a curl tail does not. Personally I havent had time to figure it out as the to reasoning why but I know it works and I was pretty shocked. If you allow 1/8" of an inch thickness on the tail they will pour with no problems. I am pretty sure once I get to fiddling with some molds I can make them work. One problem is that some guys can make curl tails pour fine in alum and others can't this has lots to do with the plastic they are using and how hot they get the plastic. so to make it easy and not break any promises I just tell people they have to pour the tails seperatly. this causes less grief in the end. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted December 8, 2008 Report Share Posted December 8, 2008 As mentioned by Del, it is a question of thermal conductivity. Only two metals conduct heat faster, those are copper and gold. Plaster is just about the opposite. It is a good insulator, so the plaster does not soak up the heat of the plastic. The down side is that you have to wait much longer before opening the mold to retrieve your cast. Thermal Conductivity of some common Materials link to thermal conductivity of different materials. Aluminum 250, plaster 0.48. huge diference. Don't you just love science. Dave Quote Link to comment Share on other sites More sharing options...
GB GONE Posted December 8, 2008 Report Share Posted December 8, 2008 Along the lines of science, remember when you are venting your molds that hot air likes to rise. Air will be forced out of most of the mold cavity because the plastic will displace it easily but let nature help you pour. A vent that allows the air to rise out vs being forced out downward will function better. I try to point my vents upward if possible or at least in a neutral (horizontal) position. Jim Quote Link to comment Share on other sites More sharing options...
Mad Eye Posted February 6, 2009 Author Report Share Posted February 6, 2009 Long time since i have been on here. Was just in the process of getting things up and running when my dad sudenly passed away from a heart attack (only 50 with no health problems !!). This put a stop to the bussiness as had to move back in with mum to support her. Ready to pick back up where i left off. Jim thoose baits are amazing!!!! Would you be mind posting a pic of the new mold. Did you use as much venting as before???? Also did you make the master yourself or just use a premade plastic to make the mold. Huge props again Quote Link to comment Share on other sites More sharing options...
