Pararaucaria branch with cones mold.
We started with a clay base. The clay must extend to a mid-point on the specimen. This will help ease the stress on the original and cast during the demolding process. The third and fourth photos show the build up to mid-point on the limb and single cone.
With alignment blocks (Legos), and sprues in place the specimen is ready to have the last portion of the mold frame attached and ready to pour the first section of the mold.
Photo #9 shows the specimen with the first piece of the mold poured. If you have seen some of our other mold discussions you may have noticed that the frames for those are built a little more sturdy. That is because the frame will be placed in the pressure bed and subjected to 80 PSI. This particular mold will not need the frame when casting is done and only needs to be strong and well made enough to keep the silicone from leeking out. Therefore, once the mold is made the frame is no longer needed and can be recycled. In photo #10 we show the second side as well poured. Only the base , with the original clay base removed is left to be poured.
The eleventh photo shows the wooden mold frame reassembled and ready to pour the last portion of the mold. As you can see in the twelfth photo the last section of the mold has been poured. Each of these sections must cure for 24 - 48 hours before you can move on to the next phase. Removing the frame and clay barriers too early (before the silicone has set up) would result in the mold needing to be thrown away. If you remove the barriers (wood or clay) and the silicone is still runny there is no way to save the mold. You must start over. The silicone is very expensive and it is not worth trying to hurry the process. So given the amount of preparation and the number of sides to be poured with this particular mold you can see that it probably took about a week to make.
Photo #13 shows the mold completely poured, cured and the sides removed. As mentioned above, each pour of the mold must cure for one to two days. The thicker that portions of the mold are, the longer it must cure. If the weather (or temperature where you are making the mold) is cooler, then you should allow for a longer curing time. If you remove the mold before it has cured, it will not have set up and will not be firm. Then you will have to throw it away and start over. Been there, done that.
The fourteenth photo shows the mold with the original Pararaucaria branch and cones specimen being removed from the mold (in front) and the first cast (in back). First the base, or larger portion was removed. Then the two smaller, top half pieces. You can see the three mold pieces with the inside of the mold exposed, to show detail.
The last photo is of a painted replica
specimen. The replica is painted a little different from the
original specimen, because we wanted to bring out more of the detail
that the specimen has to offer. The painted replica wil give you
everything the original specimen has to offer and more, with regard to
detail. The photo is also a little over exposed, so it doesn't show all of the detail that is present.
To see some of the other steps in our replica creation process, please view other pages in this web site. Also enjoy the other products and information on this web site. New additions, and updates, are made to the site monthly.
Thank you for visiting.
Specimen with clay built up around it.
Original specimen with, clay base, mid-wall, sprues.
Original specimen with mid-wall, sprues, and blocks..
First section of mold poured..
Ready to pour bottom of mold.
Mold frame removed.
Original specimen laying on clay base..
Oposite side of pecimen ready for mid-wall..
Specimen with mid-wall from end.
Original specimen ready to pour first section of mold..
Second section of mold poured.
All three sections of mold poured.
Three mold sections with cast (back) and original (front).