Ben J Posted August 13, 2007 Report Share Posted August 13, 2007 What is causing this pitting or divit looking marks in my hand pours? I am useing RTV molds that are extremely smooth. I need help please. Ben J Quote Link to comment Share on other sites More sharing options...
saint308 Posted August 13, 2007 Report Share Posted August 13, 2007 Looks like bubbles to me. Siant. Quote Link to comment Share on other sites More sharing options...
SwampBaits Posted August 13, 2007 Report Share Posted August 13, 2007 Are you sure the mold is completely smooth? The plastic is going to pick up every little detail in the mold. I've bought numerous RTV molds that look smooth, but when you pour plastic in them they are pretty much junk. Try putting some worm oil or scent in the mold before you pour (a very light coat, or it will run). See if that helps at all. Quote Link to comment Share on other sites More sharing options...
Ben J Posted August 13, 2007 Author Report Share Posted August 13, 2007 If it is bubbles. How do I fix that? It must be bubbles because the pitting is not in the same place everytime. My hard copy proto is sanded and sealed with a clear finish before making my RTV mold. Thanks for the replies. Ben Quote Link to comment Share on other sites More sharing options...
saint308 Posted August 13, 2007 Report Share Posted August 13, 2007 I would assume the bubbles are in the plastic. Do you see bubbles in your plastic? If I had to guess what is happening is after you pour, the bubbles rise to the top and as the baits cools they pop leaving the pits. I am sure someone else will chime in on this. As for getting rid of the bubbles, I just wait for them to surface and pop before pouring. Sometimes, I have to heat and reheat in short burst until they are all gone. Saint. Quote Link to comment Share on other sites More sharing options...
Ben J Posted August 13, 2007 Author Report Share Posted August 13, 2007 your right Saint, I just poured some more and saw alot of small bubbles in my plastic. I am letting them cool to see the final product. Thanks Ben J Quote Link to comment Share on other sites More sharing options...
nova Posted August 13, 2007 Report Share Posted August 13, 2007 Here's another couple of questions. Are you putting some sort of "oil" on your molds before you pour the bait? Are those baits you show heavy with salt? www.novalures.com Quote Link to comment Share on other sites More sharing options...
Ben J Posted August 13, 2007 Author Report Share Posted August 13, 2007 Nova, No I have'nt been putting any oil in my molds before pouring. I also have no salt in this bait. Ben J Quote Link to comment Share on other sites More sharing options...
nova Posted August 13, 2007 Report Share Posted August 13, 2007 The only other thing would be the bubbles then. Are you using a wooden stick to stir the plastic? www.novalures.com Quote Link to comment Share on other sites More sharing options...
SwampBaits Posted August 13, 2007 Report Share Posted August 13, 2007 Pour two baits, then compare them. If they both have the same blemishes then it's the mold, if not, then it's bubbles. Quote Link to comment Share on other sites More sharing options...
Ben J Posted August 13, 2007 Author Report Share Posted August 13, 2007 Nova, no I am not useing a wooden stick to stir with. Should I be? Quote Link to comment Share on other sites More sharing options...
One Sock Posted August 13, 2007 Report Share Posted August 13, 2007 No don't use wood als check the temps on your plastic, the hotter the plastic the more likely you will get some bubbles in it, stir good and then stir again Quote Link to comment Share on other sites More sharing options...
nova Posted August 13, 2007 Report Share Posted August 13, 2007 Absolutley not. I use old table knives; or at least I told my wife they were old; lol. Wood will put bubbles in the plastic. When you stir the plastic don't do it too fast ( don't try to make whipped cream). That will definatley make bubbles. Stir like you would a cup of coffee. Heat you plastic in bursts if you are using a micro and stir between each burst. Don't try to heat the plastic too quickly; this is something you can't rush. Everything you do with this hobby/addiction is slow and steady. What brand of plastic are you using? www.novalures.com Quote Link to comment Share on other sites More sharing options...
Delw Posted August 13, 2007 Report Share Posted August 13, 2007 I had that same problem when I first started using RTV and pouring, to be honest I never figured it out. I am pretty sure it was do to the oils in the RTV or spots that the plastic was just voided from kinda like fish eye in paint. I am sure Chris from als worms has an answer cause if I remember right way back on the old tacklemaking board he was the one who helped me out ( hopefully he is not to old to remember LOL) bubbles in plastic doesn't usually happen on the part that touchs the mold as bubbles will rise in the heated plastic Delw Quote Link to comment Share on other sites More sharing options...
Ben J Posted August 14, 2007 Author Report Share Posted August 14, 2007 Nova, I am using Lure craft plasitcs and have used M-F in the past. Del could it be the RTV mould itself? Ben J Quote Link to comment Share on other sites More sharing options...
Delw Posted August 14, 2007 Report Share Posted August 14, 2007 Ben. I don't do enough rtv molds or pouring in RTV to even guess, the only thing is when I first saw this pic and the problem you described it came in my mind to be A "Normal problem", like I said if I remember correctly chris was the one who helped me out on it a very long time ago. I havent poured RTV stuff in a while except maybe here and there but they are for me and I don't care what my personal baits look like, edit: Oh you know one thing I am thinking, is did you have any water or moisture in that mold? Ie clean them out with a damp towel or something? Quote Link to comment Share on other sites More sharing options...
alsworms Posted August 14, 2007 Report Share Posted August 14, 2007 Del, You're right. I am too old to remember. Seriously, I don't remember ever having this problem, but it sounds like all you guys are on the right track. If there's not indentations in the RTV mold itself, then I'd say it's bubbles in the plastic or you may have gotten moisture in the mold. Don't clean the molds with any water-based product (lots of household cleaners are exactly that.......water-based). Now that I think about it, I used a defoaming agent in the plastic years ago (Del.......this might be what you're talking about?). From what I remember, it was made for a carpet cleaner. Strange, but it worked. Can't think of the brand name (Zip....Zep.....something like that ) Anyway, if bubbles are the issue, I'd do what was already recommended. Heat your plastic until you see no bubbles before you pour. Sorry for the novel fellas. Carry on. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted August 14, 2007 Report Share Posted August 14, 2007 Has anyone built an agitator for PoP moulding. I had in mind a small cheap battery operated motor with a piece of wood epoxied to the spindle, slightly offset. The motor is firmly fixed to the tray. The offset load will set off a vibration strong enough to free the bubbles and leave you hands free. Quote Link to comment Share on other sites More sharing options...
Ben J Posted August 14, 2007 Author Report Share Posted August 14, 2007 Guys, I thank you all for the help. Maybe through trial and error I will get it fixed. Ben Quote Link to comment Share on other sites More sharing options...
Willy Posted August 14, 2007 Report Share Posted August 14, 2007 Try to put a little oil on the cavity of the mold before you pour. Mineral oil or baby oil works if you dont have any worm oil. It works for me on POP molds, but I'm not sure about rtv. Willy Quote Link to comment Share on other sites More sharing options...
