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Mold of the week in pictures

Discussion in 'Molding and Casting' started by Glen Conley, Jun 17, 2007.

  1. Ed,
    I add some caulk to the belly area of the fish to fill it out naturally. I do this by taking a tube of caulk and placing a piece of clear tubing over the end of the caulk tube. It helps to heat the end of the tubing with a heat gun first. Then I insert the tube into the anus of the fish, filling it to suit. Then I take a small piece of paper toweling and stuff it in the anus, so the caulk reimains inside.
    Then I proceed to mold the fish on the 1st side. I do not do anything to the fish prior to freezing.
    Taxi-lover,
    The material I use is play doh (for the clay...home made or store bought), and Reo-flex 40 dry for the mold material .
     
  2. GBRUCH

    GBRUCH "I am nothing without christ".....John 15:5

    early in this post I had a pic of a smallmouth blank. here it is completed.

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  3. J. Sonner

    J. Sonner New Member

    Beautiful fish Gary. Just curious what you used to paint the light scales in the dark markings? Pencils or powders?
     
  4. AndyB

    AndyB New Member

    Yes Dondi that is what i was looking for thank you, what do you guys use to fill the mold? 2 part? fiberglass?
    Great molds everyone
     
  5. A- Fish

    A- Fish Stehling's Taxidermy

    Great perch and brown Don- they both look great. You must have a pretty good mold inventory built up :D

    Gary, wow. The molding and painting on that smallmouth is truly inspiring. I may have to get out there and take one of your molding courses( if you could put up with me). You never can pick up enough tricks in this business.

    Bevis, to answer your question on mouth detail- I can't speak for Mr Bruch, but many of the closed gill molds come with a separate mouth insert. The teeth are then either made with a tooth Kit material( like epo-grip) or on large teeth, cast from the originals. You can cast the mouth detail into a closed gill fish and make it almost seamless by installing a plug into the mold.
    My favorite method is to cast the head separately, that way I can get full, seamless mouth detail ,as well as natural looking open gills. The head is then attached to your blank, like doing a skin mount. On the brown I posted, the customer requested closed gills, so I made a separate mouth plug for it. Hope that helps !!



    A biological supply company hired our firm to come up with an innovative and cost effective product for the educational market. We decided on doing a number of small fish, all half cast, that would be molded into a base/panel. It had to be durable, but still have all the intrecate detail of a high quality replica. Our final design is layed out below. We are still working out a few kinks, but it should be up to full production within the next year. We Hope to run 50 to 100 a month from this mold. We call it the Fish Collection ~


    A picture of the prototype we used to make our final production mold from:
    [​IMG]


    A close up shot of the 3" shiner minnow. It was a bit of a challenge to mold some of these small, delicate fish.

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    The production mold !
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    First production run -

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    The finished product , labeled and ready for sale ~

    [​IMG]
     
  6. Aaron,
    Very nicely done mold project ! It looks like it came out great !
     
  7. boarhunter67

    boarhunter67 Well-Known Member

    Currently, I make a sandbox and do a plaster coating. Is this what you do to each half of your fish when using the reoflex? Also, how does the cost compare to plaster. I'm looking to only use this occassionally to do big saltwater fish like salmon.
     
  8. boarhunter67,
    Cost wise....For larger fish I would not use Reo-flex, as the cost is much higher than bond/fiberglass or plaster. But if you are making a production mold for a fish...say 25" or less it works well, for example the perch or Brown trout I have posted.
    Performance wise, it is much easier for me to de-mold a cast using a flexible urethane vs. plaster or bondo etc.
     
  9. Glen Conley

    Glen Conley KARMA GOOSE R.I.P. 2006-2006

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    Catalyze with 1% MEKP

    That's what the instructions state on the label for the vinyl ester I've been fooling around with for mold making. Translation on that is, figure everything else out because you are on your own. Having been a lifetime student of The School of Hard knocks, little technicalities like that aren't going to keep me from doing anything.

    A lesson I just learned is:
    When ambient temperatures are 90 degrees F. and over, that stuff gets HOT! I am talking so HOT you can't touch it. I am talking so HOT that it melted my Klean Klay flange dam 2 1/2" out. Don't think that doesn't make a guy say something that sounds an awful lot like, "Oh poop!". It's "normal" exotherm (heat) production isn't much more than warm, one of the reasons I've been using it.

    Strange stuff. Everything would go about like normal as far as mixing and application, catalyzing would go along about like normal until about twenty-thirty minutes later. Then it would start turning purple in one spot (the purple is REAL HOT), and then go through the whole mass, including what had already been laid down, producing the extreme heat. It was just the same as no warning.

    The heat problem did not start until after I had made the initial lay-ups over the sculpture. I had just made my most precise flange dam yet, I keep shooting for as close to perfect in that area as possible so that if everything goes well, the mold seam line will only be 1 to 2 mm wide under pressure. Not only did the flange dam distort, but the flange at the backboard had pulled away about 3/16". This is another critical area. If the two mold halves do not butt up evenly against the backing plate for the mold when the foam is poured, the escaping foam pressures can distort the mold alignment and finished form. I could see things had gone wrong on the surface, but I had no idea as to what was going on with the mold cavity.

    I had too much time in the sculpture, and the money had already been spent for the mold making materials. I decided to go ahead and finish the mold. Worst case scenario, I would still be able to use the mold to make a foam armature to sculpt over, which would take less time than starting over from scratch.

    I finished up the HOT side, flipped it over pulled the clay dam to see that my seam line had stayed in place except for a real short right between the eyes. I had a fraction of an inch of wave in the line there. I could not tell if it was only a wave in the seam line, if so no big whoop, or if the wave meant that the eye socket on that side had warped out. If the eye socket had shifted, I'd be looking at a reject mold.

    I had started the HOT side with a fresh batch of ester. I had enough left from a previous order to finish the remaining half. Since I didn't know at the time as to what was causing the problem, I finished up the other side with the "old" stuff with no problems, but the room temperature never went over 88.

    After I got that far, I called up the tech for the company I buy my materials from, and said to him, "You remember that time you started to tell me about the behavior of vinyl ester at high temperatures and I said I don't have to worry about that, that NEVER happens around here? Well, here's what's happened.".

    He confirmed that 90-95 degrees is a magic number for the stuff to catalyze really rapidly, and really HOT, unless the catalyst is cut back to 1/2%. I also found out that the stuff will catalyze with just a heat source, such as setting a can in the sun.

    Another reason for playing with the stuff is because it repairs quite well. I had already done a few small repairs with it, and they could not be seen with the eye, or felt with the finger tips.

    Before opening the mold, I set the mold up nose down, leveled the back, clayed in around the shoulders of the sculpture, struck the clay off to level with the back flanges, and spooned in vinyl ester to level. One blister was right at 3/16" deep. The repair came out as good as "original equipment".

    I'm now ready to split the mold, open that rascal up, moment of truth, damn, I had that anxious dread feeling.

    I had made the sculpture out of several different materials. I started with my foam armature, and then used body filler, some Apoxie Sculpt, some Magic Sculpt, automotive surfacing putty, sandable primer, lacquer, and Klean Klay to fill small blemishes and under cuts, like in the nostril openings. This produces a hard, slick sculpture once there's a few gallons of elbow grease thrown in on top of it. I was figuring by making the sculpture this way, odds were pretty good I could break it out of the mold, have minimal repair to possibly the head, and then just sculpt the neck to the next size up.

    On splitting the mold, the fried side popped off first. The heat had melted all the materials except the foam. What was amazing was that the print surface of the mold was good! The sculpture looked like it had been in a fire, literally. There were a number of spots that had fused to the print surface, I was able to break those spots loose by pouring boiling water on that material until it softened back up. Vinyl ester is very heat resistant once it has cured, another reason I've been fooling with it. My guess is that if I had done this sculpture out of modeling clay, it and the mold would be trash.

    The opposite side popped out of the mold with no damage, other than the clay in the nose hole sticking to the mold. That's really what I wanted the whole thing to be like.

    I can't believe you just read all of that.

    Well, while you're here, here's some pictures. I think it is neat the way that a photograph of a mold cavity can be made to look convex if the light is just right.
     
  10. Glen Conley

    Glen Conley KARMA GOOSE R.I.P. 2006-2006

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    Addition:
    After seeing the way the original sculpture had been fried, I just still wasn't believing that the mold interior could still be good. That's bad isn't it?

    The mold will not be shipped out for another day or two. By the time it gets shipped, gets there, forms poured, forms get shipped back to me, that's going to eat up a week and a half. I really didn't want to wait that long to see the actual molded head. I had some old foam left that was "almost" still good, so I made a plug to fit the mold interior behind the head. The plug would allow pressures to build up and give a more accurate look of what the production pieces would come out like. The last photo is the end result. The film you see in a couple of places around the head is the untrimmed flashing.

    I'm still shaking my head, not believing that mold didn't get trashed out from the heat. Color me lucky, I was needing it!
     
  11. Glen...Excellent post on molding a sculpted mannikin !

    I just completed a molding project from a customer Brook trout, and I thought this info would help others. In my opinion, this is the best way to ensure good results. (No movement of the skin in the molding process).

    Step1: Skin the fish, making a belly incision, and place skin in your degreasing solution. I like to remove the fins as well. They can be carded now or frozen in a dish to mold later. Then Mold the head, rather than freezing it to do later.
    Molding the head is done in one pour. I like to take a plastic container, place a base of bedding material (play-doh) in the bottom. Then fill the back of the head as well. Now set the head carefully in the container. Open the mouth to the desired position. Then mix your molding material and gently pour into the container filling the mouth and over flowing the top of the head. Let dry for 4 hours and demold. This will create a complete head mold with a fine mouth interior.
    I use Smooth-sil 920 from smooth-on, but many other materials will work. For example platsil 71-20 from Polytek. Both are platinum cured rtv rubbers, 1:1 mix ratio, 4 hr. demold time.
     
  12. Step 2: Then mount the skin to your carved body. ( I used a commercial body, that I sculpted the back going up to the dorsal area, modified the belly area, and added fin pockets.) Let dry. Then you can mold your fins. This can be done to carded dried fins or to fins you have frozen when skinning out the fish.
     
  13. Step 3: Once the body is dried out, Finish the belly seam. Then I like to seal with fungicidal sealer, then gloss lightly, then spray with universal mold release agent. Now you can mold as you normally would, without any concern of skin movement or associated problems with an unskinned fish. Also....you can make a "production" mold without going thru the chasing process !
     
  14. Step 4: Now you have all 3 production molds complete.
     
  15. Step 5: At this point you are ready to cast your parts and assemble your reproduction. Also, you can clean the release agent from the skin mounted body and complete the skin mount as well.
     
  16. Step 6: I would also like to mention that you can use many different materials to make your mold with. I use Reo-flex 40 dry from smooth on....Many other rtv rubbers etc. will work. The bedding that I use is play-doh. Home made or store bought. Here again, many others will do.
    I have posted below the skin mount finished. I have not yet casted a reproduction from the molds yet. I will post the pic of the replica when completed......hope this helps ;)
     
  17. Ken,
    I added more info to step 1 that explains the process of molding the head. You will mold the entire head outside and mouth interior in one pour. Basically using a cup mold and opening the mouth up to the desired position, and pouring the mold material into the mouth and over the top of the kype so that the whole head is molded.
     
  18. GBRUCH

    GBRUCH "I am nothing without christ".....John 15:5

    Only problem with molding skin mounted fish is your anatomy needs to be very good and the skin will dry flat and you will not get as good scale definition.
    One thing to note--Carve your own mannikins---It is not wise to mold skin mounted fish on commercial mannikins--it is at best unethical and may be illegal---even if they are altered.
     
  19. Gary,
    Unethical ? Illegal ? Wow....
    If I molded the commercial body as it came from the vendor, and went into the business of selling the commercial bodies, I could see your point. But that is not what I did.
    Leave it to you to find something....oh well, your the expert.
     
  20. jeremy

    jeremy Have you hugged your snake today!

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    Don or Gary
    Ive been reading all the info here on the molding forum and think im inspired to try to cast some fish Ive never done a thing with fish as i am strictly a bird guy but last month my 7 year old caught this nice trout and so i thought its time to try.
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    Ive caught some perch ond crappie to practice on and was going to go the skin mount route but after seeing this thread i think I want to learn casting and work up to the rainbow. so let me see if I got the steps down right
    1. De-slime fish with a commercial de-slimer? 2. Cut off all the fins and cast them with fin magis as shown in Breakthrough article and reattach with magic sculpt. 3.Build a clay base with keys in it for fish to rest on/in and a mold container as shown and mold with Reo-flex to build mold. Also plump fish with caulk with plastic tube through anus. 4. clean mold and paint on a Gel-coat??? What is a good kind or brand? 5. cast fish with what? smooth cast, bondo with resin? once cured clean cast and re-assemble the fins and paint. Is this it in a nut shell. Thanks for all the info you guys have been sharing its been helpfull.
    jeremy