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Husky

DIY An Instant 1/2 Rd RTV Silicone Mold For Under A Buck.

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Tried using the silicone as a casting agent and had fairly decent results. I used a two part Plaster of Paris mold, (sealed mine with about 5 light coats of polyurethane I had laying around garage) WD40 as a release agent (also used PAM but WD40 seemed to work better) and a 35 cc syringe that i purchased at a local farm supply store. Drilled the end of the syringe out to let the silicone flow out a little easier. I would add about 20cc's of silicone and about 2 teaspoons of water. Hold the syringe in one hand with end pointing down and hold finger over it I used an old 1/2 inch spade type drill bit in my cordless drill to mix the water and the silicone together. Put the plunger into the syringe and keep the outlet closed with my finger and pushed plunger down. This helped push all the air and excess water to the end and you let a little of the air and water escape at a time till the silicone starts to come out. Modified the "pour" hole to just about the same diameter as the end of the syringe and slowly pushed the silicone in until it started to press out around the syringe. Let it sit for about 20 min and then pulled it apart. Still had to be careful pulling the molds apart as i broke a mold pulling to hard from the end. Going to try making a thicker mold next. Also I need to look earlier in this post as someone had mentioned a way to make the silicone more flexible cause these set up pretty stiff. Once I read up on how to add pics on here I'll add a couple

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Tried using the silicone as a casting agent and had fairly decent results. I used a two part Plaster of Paris mold, (sealed mine with about 5 light coats of polyurethane I had laying around garage) WD40 as a release agent (also used PAM but WD40 seemed to work better) and a 35 cc syringe that i purchased at a local farm supply store. Drilled the end of the syringe out to let the silicone flow out a little easier. I would add about 20cc's of silicone and about 2 teaspoons of water. Hold the syringe in one hand with end pointing down and hold finger over it I used an old 1/2 inch spade type drill bit in my cordless drill to mix the water and the silicone together. Put the plunger into the syringe and keep the outlet closed with my finger and pushed plunger down. This helped push all the air and excess water to the end and you let a little of the air and water escape at a time till the silicone starts to come out. Modified the "pour" hole to just about the same diameter as the end of the syringe and slowly pushed the silicone in until it started to press out around the syringe. Let it sit for about 20 min and then pulled it apart. Still had to be careful pulling the molds apart as i broke a mold pulling to hard from the end. Going to try making a thicker mold next. Also I need to look earlier in this post as someone had mentioned a way to make the silicone more flexible cause these set up pretty stiff. Once I read up on how to add pics on here I'll add a couple

What are you "shooting"? I love outside the box projects. Please post pic if you can.

You can soften up the Silicone by adding Mineral Spirits, (a few drops at a time until you get the softness you're looking for,) to it BEFORE adding water. It's a little smelly so let them cure out where the smell won't get you in the dog house. All odors will dissipate in a day or so.

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New to this board and lure making in general. I have been playing around with silicon molds for the past couple of days and this is what I've found. First off, the Walmart where I live does not carry Mainstay Silicon but another brand called ColorPlace. I have been using the white version as recommended by Husky. As for it's ability to cast an object, this stuff is really amazing. It accepts and releases plastic very well and the quality of the mold is very high. One limitation I have encountered is the amount of bubbles or air pockets you experience. Another thing I have noticed is that the amount of water you add will impact the texture, smell and volume of silicone in your end product.

For example, the first mold I cast was, like I said, my first mold. I was very excited and couldn't wait to see the finished product. I layed out som silicon, added water( no specific amount) and started turning with a puddy knife. As soon as the water contacts the silicon, you will get a white vinegar smell. Less than a minute into stirring, you will notice the silicon getting fluffy and tighter. At that point I place it in my coffin, pushed in a lure and let it set. With the exception of air bubbles, the finished product was perfect. I have cast four dozen very acceptable baits.

However, if you add more water as the silicon begins to get fluffy and set, it will keep it in a pliable state for a little while longer. When it begins to harden again, just add more water and it will stay pliable. Two things I noticed after doing this three times is thatn the smell of vinegar is lessened and the silicon seems to shrink. The amount of silicon I had at the end of this experiment was considerably less than when I started. Also, it's texture seemed to change in that it had become more supple, like silly puddy and it does not cure as quickly.

Here's a helpful hint to get a bubble free mold. Cover your finger with a piece Plastic Wrap or anything similar and apply a thin coat of straight silicone onto the model then finish it off with the water blend. The moisture will cure the straight silicone but thatb should give you that blemish free mold.

FYI the bubble blemishes can be filled in with straight silicone. Use the Plastic on the finger technique and fill in the holes, wet it down, and you should have a nicely finished mold.

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This is all good stuff Fire527.

A good while back, I added a little olive oil, just to see if I could thin the RTV down a tad. It did actually set, but took longer. I did not persue it at the time, but this time I am going to experiment with glycerine. I plan on using a cake syringe. I have used these before for injecting very thick mixes of resin and micro balloons (worked well). I figure a light coating of wax inside the syringe (thanks Husky) might aid the clean-up.

I feel that their is still lots to be discovered with this material. Thanks for leading the way Husky, great thread.

Dave

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I know this is an old thread, but I had been trying to find a way to make an inexpensive RTV mold for a long time with very poor results. But yesterday. Found this thread and it worked fantastic. So I figured I would say thanks to Husky for this great info.

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Husky - you have changed my life. I am a newbie and have made several silicone rtv molds from Oomoo and Alumilite. While I will definitely use the "good stuff" again in the future, I will be using the "Husky silicone sauce" in a lot more of my molds.

I sculpted a segmented slug from sculpey. I took my time to sand and finish the product well so that I would have many many batches of good slug jerk baits. I had made a POP mold and was pretty satisfied with it then I tried your original recipe for the 1/2 rnd silicone mold.

HOLY COW!

I was stoked by the way it came out! I have poured several baits in the mold and (other than the vinegar smell which will go away I've read) I couldn't be happier.

I will try to post some pics in a later post. If you're on the fence about this process give it a try! Its by far the most cost effective way to make a soft master using a silicone mold. I am anxious to try some of the more advanced techniques guys have been describing in this thread.

Thanks again and stay tuned for pictures later on. Will also post in the gallery as this is my official first creation of my own design (Not a copy of an existing lure).

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I'm happy that it worked well for you. Looking forward to seeing the pics. 1/2 round doesn't mean you can't get nearly full round, btw. Unlike POP, undercuts arent a problem. MP

Husky - you have changed my life. I am a newbie and have made several silicone rtv molds from Oomoo and Alumilite. While I will definitely use the "good stuff" again in the future, I will be using the "Husky silicone sauce" in a lot more of my molds.

I sculpted a segmented slug from sculpey. I took my time to sand and finish the product well so that I would have many many batches of good slug jerk baits. I had made a POP mold and was pretty satisfied with it then I tried your original recipe for the 1/2 rnd silicone mold.

HOLY COW!

I was stoked by the way it came out! I have poured several baits in the mold and (other than the vinegar smell which will go away I've read) I couldn't be happier.

I will try to post some pics in a later post. If you're on the fence about this process give it a try! Its by far the most cost effective way to make a soft master using a silicone mold. I am anxious to try some of the more advanced techniques guys have been describing in this thread.

Thanks again and stay tuned for pictures later on. Will also post in the gallery as this is my official first creation of my own design (Not a copy of an existing lure).

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Wow.  I just stumbled across this thread.  An oldie but definitely a goodie.  I'll definitely be trying some of this stuff out this weekend (after I get back from trout fishing).  Tons of info.  Everyday I learn something new here.

Thanks to all

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It works really well.  I put a thin film of unwatered silicone directly onto my master first, to be sure it's in all of the detail fully.

I wait 24 hours to remove the master.  The watered silcone adjacent to the master would probably help the unwatered stuff to set faster, but I don't want to take a chance.

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