Best way to create mold from a real fish?
27 replies to this topic
Posted 31 December 2008 - 03:17 PM
I'm interested in designing some baits that will be exact replicas of real fish initially before I create the various segments for swimbaits etc.
What is the best and still affordable way to mold a dead fish to create a mold for prototyping? Has anyone actually done it and how did it turn out?
Posted 31 December 2008 - 04:45 PM
I'd go with alginate, it cures quick & captures detail like RTV. You won't have to worry about anything on the baitfish reacting with the alginate.
After you have the alginate negative, cast a plaster positive from that.
Then you can tweak the plaster once it dries & then cast a final silicone negative.
Pay attention to the cure times, the alginate I use is dental alginate and sets off in 30 seconds with warm water.
Ice cold water helps slow the cure. Even better......freeze the baitfish first to make it easier to work with.
There's a thread going on about alginate right now:
Posted 31 December 2008 - 04:50 PM
Thanks so much for the reply. I did see that thread and wondered if anyone has used it to mold a real fish before. I'll have to check into that stuff.
Posted 01 January 2009 - 02:09 AM
I have toyed with this idea over the yrs too but never got around to it. I always thought I would freeze the critter first and then mold it. Smoothon has some info on their site about taxidermy so you might look there. Ultimately you may find that carving a prototype of your piece is more accurate altho some recent bass baits look to me like they were made from a real fish.
Posted 01 January 2009 - 02:47 AM
Bondo followed by fiberglass wool/resin for strength. I have come across it several times on the web. The pectoral and pelvic fins are generally removed. The fish is embedded in medium half way like typically observed for cranks or soft plastics and then the bondo body filler painted over the fish. Let set and then hit with resin and fiberglass. This will give you longer lasting mold.
I am sure someone has a link. I lost all mine when my computer crashed months ago.
Posted 01 January 2009 - 11:56 AM
Crawchuck, had attemped to mold a fish using a quicksetting drywall compound and the fish stuck to the mold. I think using a molding material that is quick setting and doesn't pull moisture from the specimen would probally yield the best results. As Travis mentions bondo, which some brands (older formulas) will draw moisture. However if one would use the resin first, and then bondo. I can't see why it would't work> Taking care not to mix too much hardener resulting in a significant amount of heat generated during the curing.Which could distort or degrade the fish.
Posted 01 January 2009 - 12:30 PM
I just realized that you can buy fish blanks for taxidermy purposes. As long as the fish is three dimensional and is in a straight position I could use one of those to create the RTV mold.
What I want to do is to have the actual fish shape made from Featherlite and then I can go about using the bodies to experiment with joint placement, weighting etc with an anatomically correct shape.
I'll have to see where I can pick up some bodies here in Canada that are reasonably priced and the appropriate size for what I need.
I don't imagine that there's a huge demand for 10" Walleye mounts! lol
Posted 01 January 2009 - 04:14 PM
I looked at that too over the years Mike. What I found is the taxidermy specimens generally have either a left or right turn which won't work for us. The other thing is their fins are really thin so you can't use them either.
In the end, I still think building your own proto will be the best because you can set the species you want, the width, length, etc.
Posted 01 January 2009 - 05:00 PM
I'd bet that if you misted some mold release or silicone on it first, you'd eliminate the sticking.
Posted 01 January 2009 - 05:26 PM
This is how I would do it. Visit to the plumbers section of the hardware store, buy some plastic pipe of a suitable diameter. Split the pipe down the middle, table saw would make light work of this.
Tape the two halves together with some of Rookies duck tape.
Plug the bottom by pressing the tube into a flat slab of soft modelling clay.
Hang the fish vertically, nose up, by a thread (bottom lip), inside the tube.
Mark the tube to indicate the top and bottom centrelines of the fish.
Very quickly, mix the alginate and fill the tube, bearing in mind, you only have seconds. A few practise runs will inevitably be required to get a feel for the material.
Cut the tape down one seam and remove the fishy mold from the pipe, not forgetting to transfer the c/l to the alginate cast.
With a sharp box cutter or scalpel, make a single cut around the fish. Split the mold and remove the fish. No need to be too tidy, as the imperfections will act as mold location.
Clean any debris from the mold. Cut a pour hole. Re-assemble the two mold halves into the pipe. And pour the Plaster of Paris. With care, it should be possible to get two or three plaster casts from the mold, but all has to be done within a few hours.
This method is based loosely on the first tutorial I ever read on TU, I think it was entitled slip mold, excellent tutorial. I have actually used this method for making a copy of a lure body carving, except I used a mug in place of the pipe. It worked just fine.
Edited by Vodkaman, 01 January 2009 - 05:30 PM.
Posted 01 January 2009 - 06:46 PM
If you can get your hands on some liquid nitrogen I think it would be best to "flash freeze" the fish first to provide the freshest detail. In order to keep your fish straight (and prevent degredation) you should also euthanize first. Believe it or not, seltzer water can be used for euthanasia. However, I don't know the correct mix of seltzer water to h2o. My advice is to pour a little in a 5 gal bucket over the matter of 3 minute intervals until the fish looses its ability to regulate its air bladder. If you somehow have access to MS222 (found in aquaculture labs) this is prefered but very $$$. Either way, once the fish is euthanized you have a few minutes to figure out how to flashs freeze the fish w/out it flopping.
Posted 01 January 2009 - 06:58 PM
I've just ordered a fish blank from a taxidermy supplier and I'll be using it for now to experiment. The blank was molded from a real fish so it will save me the trouble. The size was what I wanted too.
I'll be posting the results once I have tinkered with it.
Thanks again to all who posted.
Posted 06 January 2009 - 10:23 AM
why not use silicone for the mold? This stuff doesn't stick to anything except silicone, so as long your fish doesn't have (leaking..) breast implants it should work right...?
Posted 06 January 2009 - 10:49 AM
Hmmm....If the fish is from L.A. it might have implants!
Posted 06 January 2009 - 11:42 AM
I'm sure you could sue the implant manuf. and retire.
Posted 07 January 2009 - 01:54 AM
My questions is if your using a real fish to mold the bait.. are you going to have a real artist paint it?
Posted 07 January 2009 - 07:44 AM
Rookie, maybe he could get a hold of the same artist that Tater uses!
I'm still mulling over euthanizing a gizzard shad...do NOT let this info make it to some of these educated predators we fish for, I think some of them would be smart enough to use it!
Posted 08 January 2009 - 04:18 PM
Since you're having a good laugh about my artistic abilities I thought I'd share a recent airbrushed portrait I was commissioned to do by my girlfriends office...