Thought I would do a quick write up on how I've made my fake buttressed tree for my 340 gallon tank.
I decided early I wanted a big buttressed tree trunk in the corner of my viv. I spent hours and hours just browsing pictures of buttress roots from all over the world. One day it kind of hit me. The trunks and roots had a very draped fabric look to them. Like the bark and outer trunk consisted out of a loose draped fabric. The wrinkled bark where it twisted. The cross section of the trunk looking like a heavy curtain. And then I knew how I would try and construct my fake tree. Fabric!
This technique is not new but I haven't seen it applied to fake trees before. You basically drench a piece of fabric in a cement, concrete or hypertufa mix and hang it up to dry. Fabric formed concrete is also used when casting to get organic soft shapes. Google "fabric formed concrete" and you'll see some cool things!
First I did some rough of the tree's cross section up where it will meet the top of the viv. I wanted some form of rigid shape to hang the fabric from that would give it its initial shape. I used some rope and thick aluminum wire for this. Looking back I don't really know why I used the rope, you certainly don't need it.
I also did some small scale experiments using a piece of fleece blanket that I drenched in a runny cement mix. They dried super hard and very light.
Next step was to make a stand from where I could hang the fabric to dry. I had a few styrofoam sheets that I put together for this. I needed to be able to lower the fabric down into the cement mix and then pull it up and secure it so I made a series of holes through the top and tied string to the "armature" and attached fabric.
I made a mix of pure portland cement and water. Had a very runny consistency. I put in the fabric and made sure it was soaked through everywhere before pulling it up and hanging it. It was very heavy at this point but draped beautifully in the shape I wanted.
I let this harden for about 24 hours before moving on to the next step, the actual buttress roots. At this point all I had was the trunk.
I decided to use some aquarium water hose to make the shape and support for the roots. The hose bends very nicely in soft bends that looks very natural. I used wooden skewers to hold the hose in place to the styrofoam and screwed the hose to the trunk together with some hot glue.
Then it was just a matter of fitting and cutting out pieces of fabric to drape over the hose.
Then I drenched those pieces and hung them over the hose. Tried to straighten out some wrinkles I didn't like. The blanket I used wasn't very stretchy so it wrinkled very easily when you forced it into some shapes. If I'd do this again I would try and find a more stretch fabric.
After hardening it looked like this. It was very hard and stiff but surprisingly light.
I continued the same process for the last two roots.
After it had hardened I cut it down to the final height using a hacksaw blade. You can see how thin the wall is.
At this point it didn't really have a nice and natural texture to it. I decided to try and give it a coat of cement mixed with coco peat. Cement to peat ratio 50/50. Mixed it to a milkshake consistency and applied it with a normal paintbrush. Brushing and stippling. Using an old fork to add some more details.
Finally just for the fun of it I positioned some of the wood I have to see what it would look like.
There's where it is at the moment. What about sealing? Well, the only real problem with portland cement is the very high alkalinity that you have to bring down somehow. It will do so naturally from the CO2 in the air (carbonatation) but it can take some time. An engineer friend I talked to said that usually it takes concrete 25 years to get carbonated (right word?) 10mm below the surface. His guess was that pure cement like I used will reach that in just a few weeks.
I think I'll attack that issue by sealing the backside of the tree with sodium silicate (water glass) and apply a acid wash to the front. Then attaching a support to the inside using thin pvc pipes and just spraying them into place with pu-foam. So even if the acid will weaken it some it will be supported and not collapse.
I decided early I wanted a big buttressed tree trunk in the corner of my viv. I spent hours and hours just browsing pictures of buttress roots from all over the world. One day it kind of hit me. The trunks and roots had a very draped fabric look to them. Like the bark and outer trunk consisted out of a loose draped fabric. The wrinkled bark where it twisted. The cross section of the trunk looking like a heavy curtain. And then I knew how I would try and construct my fake tree. Fabric!
This technique is not new but I haven't seen it applied to fake trees before. You basically drench a piece of fabric in a cement, concrete or hypertufa mix and hang it up to dry. Fabric formed concrete is also used when casting to get organic soft shapes. Google "fabric formed concrete" and you'll see some cool things!
First I did some rough of the tree's cross section up where it will meet the top of the viv. I wanted some form of rigid shape to hang the fabric from that would give it its initial shape. I used some rope and thick aluminum wire for this. Looking back I don't really know why I used the rope, you certainly don't need it.
I also did some small scale experiments using a piece of fleece blanket that I drenched in a runny cement mix. They dried super hard and very light.
Next step was to make a stand from where I could hang the fabric to dry. I had a few styrofoam sheets that I put together for this. I needed to be able to lower the fabric down into the cement mix and then pull it up and secure it so I made a series of holes through the top and tied string to the "armature" and attached fabric.
I made a mix of pure portland cement and water. Had a very runny consistency. I put in the fabric and made sure it was soaked through everywhere before pulling it up and hanging it. It was very heavy at this point but draped beautifully in the shape I wanted.
I let this harden for about 24 hours before moving on to the next step, the actual buttress roots. At this point all I had was the trunk.
I decided to use some aquarium water hose to make the shape and support for the roots. The hose bends very nicely in soft bends that looks very natural. I used wooden skewers to hold the hose in place to the styrofoam and screwed the hose to the trunk together with some hot glue.
Then it was just a matter of fitting and cutting out pieces of fabric to drape over the hose.
Then I drenched those pieces and hung them over the hose. Tried to straighten out some wrinkles I didn't like. The blanket I used wasn't very stretchy so it wrinkled very easily when you forced it into some shapes. If I'd do this again I would try and find a more stretch fabric.
After hardening it looked like this. It was very hard and stiff but surprisingly light.
I continued the same process for the last two roots.
After it had hardened I cut it down to the final height using a hacksaw blade. You can see how thin the wall is.
At this point it didn't really have a nice and natural texture to it. I decided to try and give it a coat of cement mixed with coco peat. Cement to peat ratio 50/50. Mixed it to a milkshake consistency and applied it with a normal paintbrush. Brushing and stippling. Using an old fork to add some more details.
Finally just for the fun of it I positioned some of the wood I have to see what it would look like.
There's where it is at the moment. What about sealing? Well, the only real problem with portland cement is the very high alkalinity that you have to bring down somehow. It will do so naturally from the CO2 in the air (carbonatation) but it can take some time. An engineer friend I talked to said that usually it takes concrete 25 years to get carbonated (right word?) 10mm below the surface. His guess was that pure cement like I used will reach that in just a few weeks.
I think I'll attack that issue by sealing the backside of the tree with sodium silicate (water glass) and apply a acid wash to the front. Then attaching a support to the inside using thin pvc pipes and just spraying them into place with pu-foam. So even if the acid will weaken it some it will be supported and not collapse.