Monday, October 8, 2012

Rocks, Rocks everywhere.

Rocks, Rocks everywhere.

Well mainly in my head some would say (Grin)!

Trying some new stuff this weekend: Bragdon Enterprise Molds and Dental Plaster.

Got 6 molds all excellent quality and Joel Bragdon is first rate (no affiliation just a very satisfied customer).

Here are the molds:

This mold is large, about 2 feet wide and 18" tall. Start with a smaller mold to learn. This large mold takes some practice.


This is one great mold, lots of detail and a easy beginning one to learn.


This mold is also easy to use and makes a nice solid rock casting with limited depth, great where you don't have much depth.


This mold is deeper and has great texture. Little harder to use.


Limited depth, nice striated rock, easy to use.


This is the retaining wall mold. Cheaper than the Noch flexible and conforms to base.


Using Molds:
I had little experience with wet molds, mainly a few Color-rite (nice molds, inexpensive but not in the same league as the Bragdon molds). Add 0 experience with Dental plaster and the first 3 tries were a disaster. The 4th try was when it started to gel. First the Plaster said 44-45 cc water to 100 g plaster. Found this was a little too thick, so used 50 cc and decreased plaster by 10%, so 50cc water to 90 g plaster.


Loading plaster to water required constant agitation or stirring. don't dump all in at once but add slowly and let water absorb plaster. after about 1/2 in it will require constant stirring, not circular but back and forth.

Once all entered make sure all lumps broken up. You want the plaster like pancake mix. bounce mixing bowl to remove any bubbles. Pour in mold and use spatula to spread over mold (makes sure to spray mold with wet water before adding plaster). Use care in spreading to ensure no open spaces or trapped air.

Applying molds:
Spray receiving surface with wet water. Once mold begins to film over you can slide a hand under the mold and lift. This takes some practice. Small tiny cracks are ok, larger cracks mean it is too far set and will crumble when applied. This is the hardest part, but after doing a few you will get the feel.

Place where you sprayed and press and hold. I hold anywhere from 60 seconds to 2 minutes depending on how it is adhering. Subsequent molds can over lap. The amount of pressure will let you vary the mold depth and shape.


Here is a mold drying in-place. Paul Scoles removes his after a few minutes, I'm still trying to get a feel for this. Waiting 15 minutes works but makes and carving difficult.


Overflow can be chipped off to make castings blend together. Paul recommends a Dental Pick.

Results:

This is the first mold shown above. Took me 3 tries to get a good casting. This is looking down grade from Beaver Brook.


This is mold 2, looks really good. This is Forks Creek.


This shows 2 molds together just downgrade from Forks Creek.


This is Forks Creek with 3 castings in-place.

So much to learn. Made some progress, but a lot more to do and learn. Plan to do more casting tomorrow. Will try Paul's way and remove molds earlier so I can chip any excess away. Of the 50 lbs of plaster I got in, used almost 1/2.

One thing that I want to try out is only filling part on the mold to give more variety.

Any hints always appreciated.

Thanks Cameron

No comments:

Post a Comment