Post by jscanlan1 on Feb 23, 2010 19:45:33 GMT -5
There are many ways to mold a fish head, so I thought I’d share mine. I use this method because I like the detail that using silicone gives and allows me to use small amounts of silicone to cut down on expense. I also love how this method allows for great mouth detail which allows me to bypass using a mouth plug which I am not that comfortable using. The down side to this method is you get one shot to use the mold, so your first pull has to be a good one. I’ll also add this method is not for production casting, but can be used to cast your prototype.
Materials: Quick curing tin-cured silicone, Bondo, and urethane plastic, mixing cups and sticks.
The use of a quick curing tin-cured silicone; has two purposes one it is quick curing, the one used here cures in 75 minutes. Second being tin-cured it is less expensive and it is more forgiving than platinum-cured silicones which may not cure if the fish is not completely dry. The fish being used here is a 20” hen brook trout. This method can be used with a closed mouth or with an open mouth/ closed operculum, this method will not well with the flaming bass looking (open mouth/open operculum) that requires a more advanced method.
Step one- is to wash the fish off in cold water to clean off any slime. Don’t forget to clean in the mouth and under the operculum cleaning the slime off of the gills, rakers and gullet. Then dry the fish including the inside of the mouth, gills, etc. Dry as good as you can.
Step two- is to position the fish in an upright position, making sure the operculum are free. Mix up a small amount (30cc) of silicone and pour in the fish’s mouth coating everything. Some of your silicone will run out below the operculum which is O.K. for now. This coat is used to mold the mouth and seal the mouth so your next pours of silicone won’t run out under the operculum. Let cure. After curing slightly lift up the operculum and trim off any silicone that has run out, other wise it will stick the future pours encasing the head.
Step three- mix up another batch of silicone (60cc) and pour in the mouth and then over the head of the fish coving all the head. Let cure.
Step 4- Cut up some extra cured silicone into small chips and drop it in the mouth to fill up the mouth, then mix up another batch of silicone (60cc) and pour in the mouth and over the head. The fresh silicone will combine with the chips and become one, making the mouth mold sturdy. Let cure.
Step 5- Mix up one more small batch of silicone (30cc) and pour over everything. Let cure. Approximately 5 hours has passed from start to this point.
Step 6-After silicone is cured apply a thin coat of straight Bondo about 3/16” thick or thicker if you want. This will act as the “Mother Mold”. After the Bondo is cured than you can carefully demold the fish.
This picture shows the inside of the mold.
Step 7- now is the time to clean up the mold, trimming away any severe undercuts. Also now is the time to trim off the gills, leaving just the impression of the gill arches. If you don’t do this it will be impossible to remove the silicone after it is casted. Picture of the mold all cleaned up.
Step 8- is to cast the fish head, no mold release is needed. You can fill the mold with urethane plastic and make a solid cast, which you will dremel out later to your specification. The other way to cast is put some urethane plastic in the mold and rotate it around covering all parts of the mold. This produces a thin shelled mold, usually requiring at least two applications of urethane to make sure the walls are thick enough. Here are some pictures of the finished head, notice some of pits from where the customer had vacuum-packed the fish. These will easily be smooth over with epoxy. Remember the cast will never be better than what is molded. Total cost in supplies is around $11.00
Here is a carp done by this method.
Materials: Quick curing tin-cured silicone, Bondo, and urethane plastic, mixing cups and sticks.
The use of a quick curing tin-cured silicone; has two purposes one it is quick curing, the one used here cures in 75 minutes. Second being tin-cured it is less expensive and it is more forgiving than platinum-cured silicones which may not cure if the fish is not completely dry. The fish being used here is a 20” hen brook trout. This method can be used with a closed mouth or with an open mouth/ closed operculum, this method will not well with the flaming bass looking (open mouth/open operculum) that requires a more advanced method.
Step one- is to wash the fish off in cold water to clean off any slime. Don’t forget to clean in the mouth and under the operculum cleaning the slime off of the gills, rakers and gullet. Then dry the fish including the inside of the mouth, gills, etc. Dry as good as you can.
Step two- is to position the fish in an upright position, making sure the operculum are free. Mix up a small amount (30cc) of silicone and pour in the fish’s mouth coating everything. Some of your silicone will run out below the operculum which is O.K. for now. This coat is used to mold the mouth and seal the mouth so your next pours of silicone won’t run out under the operculum. Let cure. After curing slightly lift up the operculum and trim off any silicone that has run out, other wise it will stick the future pours encasing the head.
Step three- mix up another batch of silicone (60cc) and pour in the mouth and then over the head of the fish coving all the head. Let cure.
Step 4- Cut up some extra cured silicone into small chips and drop it in the mouth to fill up the mouth, then mix up another batch of silicone (60cc) and pour in the mouth and over the head. The fresh silicone will combine with the chips and become one, making the mouth mold sturdy. Let cure.
Step 5- Mix up one more small batch of silicone (30cc) and pour over everything. Let cure. Approximately 5 hours has passed from start to this point.
Step 6-After silicone is cured apply a thin coat of straight Bondo about 3/16” thick or thicker if you want. This will act as the “Mother Mold”. After the Bondo is cured than you can carefully demold the fish.
This picture shows the inside of the mold.
Step 7- now is the time to clean up the mold, trimming away any severe undercuts. Also now is the time to trim off the gills, leaving just the impression of the gill arches. If you don’t do this it will be impossible to remove the silicone after it is casted. Picture of the mold all cleaned up.
Step 8- is to cast the fish head, no mold release is needed. You can fill the mold with urethane plastic and make a solid cast, which you will dremel out later to your specification. The other way to cast is put some urethane plastic in the mold and rotate it around covering all parts of the mold. This produces a thin shelled mold, usually requiring at least two applications of urethane to make sure the walls are thick enough. Here are some pictures of the finished head, notice some of pits from where the customer had vacuum-packed the fish. These will easily be smooth over with epoxy. Remember the cast will never be better than what is molded. Total cost in supplies is around $11.00
Here is a carp done by this method.
? Looking for a wayto fix broken fins on already mounted fish...And how to blend the color to match the fish already painted??? need some help please!!!!!