borderbasser Posted March 20, 2006 Report Share Posted March 20, 2006 Ok, I have two questions. #1 Has anyone used bondo body filler for a soft plastic mold? If so how do the finished products compare to those that came from resin? Can you make a two piece mold without the problems of warping like the resin? Do you need to seal the cavities? #2 Has anyone had any success making a one piece mold of a fluke out of resin. Does anyone have any tips on how to ensure that the split belly fills completely with the resin? I'll be using masters from my Del 7in. fluke mold. I have a fairly large order to make for a guy and my 3 cavity mold ain't gonna cut it Thanks for any help! TJ Quote Link to comment Share on other sites More sharing options...
Dungeonhawk5 Posted March 20, 2006 Report Share Posted March 20, 2006 to be really honest ive found more and more lately that my resin molds just dont cut it... the baits come out lighter, like not nearly as much plastic is being used.. the tails of beavers are thinner.. there is about 1/8 inch shrinkage from the original... for personal use, there is no problem at all with resin, although I i would caution using it if you are going to sell your baits.. especially on smaller ones.. someone may post something completely to the opposite however.. i just say use caution Quote Link to comment Share on other sites More sharing options...
Travis Posted March 20, 2006 Report Share Posted March 20, 2006 Bondo body filler works fine for making molds. Easy to do and quick. Best part it is really easy to work with. I have made "several" molds from it. Two piece molds are no problem either. Matter of fact they come out better than durhams or plaster. They do need to be sealed with devcon. Forget molding in the hook slot. easier to fill slot with clay, and cast the mold as if the body was going to be solid. Now go back and drill series of holes or if you have milling vice and drill press put a slot in the base and glue in a thin wood strip or series of skewers. Then go back and seal with devcon as usual. Unless you decide to make the hook slot wider most of the time I find them to be to "brittle" to cast using durhams or paris. Now RTV is another option it will do just fine. Quote Link to comment Share on other sites More sharing options...
nova Posted March 20, 2006 Report Share Posted March 20, 2006 Has anyone ever tried to mix resin with bondo or resin with plaster;or am I asking a silly queston? Quote Link to comment Share on other sites More sharing options...
jm Posted March 20, 2006 Report Share Posted March 20, 2006 The only silly question is the unasked one. :grin: Has anyone ever tried to mix resin with bondo or resin with plaster;or am I asking a silly queston? There are several systems to make molds. From cheapest to expensive, here they are. Plaster is a water cure calcine product that produces a stone, the shrinkage is minimal, it is brittle, and porous. There are latex resins that some people use. These are the molds that turn yellow as soon as you use them. I don't think they are very suitable for hot melt plastisol. Eurethane resins fall into this category also. They mix up like water, and cure hard in minutes with little shrinkage. They are not as heat resistant as polyester resin. I have been told that they can be modified like other resins with fillers like aluminum oxide that will make them suitable for plastisol molding. They are cheaper than polyester resin. Resin, aka bondo, or polyester resin, is a liquid plastic that cures with MEKP, (aka peroxide, not to be confused with hydrogen peroxide). It forms a tough hard plastic, is not porous, but shrinks about 3% in curing. The heat of plastisol will slowly warp or change the finish of it over time. I use US Composites Silmar 41 resin. Epoxy resin is a 2 part resin that forms a tough, hard plastic that is not porous. It can be had in formulations that are very heat resistant. It does not shrink appreciably when curing, and thus can be used to make very accurate molds, if that is important. Both polyester and epoxy resins can modified by adding fillers, such as aluminum powder or oxide, to change their characteristics. Aluminum filled epoxy is used to make plastic blow molding forms, which is a high temp and pressure process compared to anything you'll see in plastisol bait making. Next is the silicone resins. The two main types are tin cure and platinum cure. Many tin cure resins are suitable for plastisol. They tend to be quite viscous (thick) but are very wet and will copy the finest detail. Platinum cure resins are more expensive, though not as much as you'd think. They can be had in formulas that can be used for lead molds. They can also be had in less viscous formulas that will speed up mold making. From what I've seen on the board, they seem to have a limited life, but for mastering it's hard to beat. Silicone doesn't shrink, and is flexible so undercut molds and masters can be made. The top of the line is CNC cut solid aluminum molds. If you don't wreck them by putting them away salty and wet, they last a life time. The shine of the bait is limited by the quality of the finish, so if Del or Bob makes them, it's incredible. (shameless plug) They cool much faster than the other materials, so fewer molds are needed for continuous production. hope it helps. jm Quote Link to comment Share on other sites More sharing options...
wannabefishing Posted March 20, 2006 Report Share Posted March 20, 2006 I was curious if anyone was using the bondo milkshake mnethod? We use it for strengthening car audio enclosures, it's a mix of 1 part bondo and 2 parts resin, with the resin catalyst used (not the bondo catalyst).... hard as a rock, can't really sand it or dremel it it's like concrete when hardened.... just a thought might give the bondo a try and see how it turns out... Quote Link to comment Share on other sites More sharing options...
jm Posted March 20, 2006 Report Share Posted March 20, 2006 Bondo is a trade name for several products. The bondo we talk about is the MEKP cured polyester resin normally used with fiberglass for body repair. Exactly what is the mixture you're talking about? It sounds interesting. jm Quote Link to comment Share on other sites More sharing options...
wannabefishing Posted March 20, 2006 Report Share Posted March 20, 2006 When you say Bondo everyone knows what it means, simplified for those who don't know lol basically you take 33% plastic filler (Bondo as everyone knows it) and mix it with 33% fiberglass resin. Stir it around a bit to mix it up, then take the catalyst from the fiberglass and add it accordingly (temp and humidity will affect how much)- you can get it to pour thick or thin, depending on the percentage of bondo to resin you put in.... I konw when i use it to build kickpanels and enclosures i use it at 33% bondo to 66% fiberglass so it will slosh around inside and fill in any holes that may be there, also to re-enforce it aswell... Quote Link to comment Share on other sites More sharing options...
borderbasser Posted March 24, 2006 Author Report Share Posted March 24, 2006 Thanks for the replys guys. I'll be trying the bodo here pretty soon. Thanks again! TJ Quote Link to comment Share on other sites More sharing options...
