Building a cave from the outside in

Usually a cave is made by digging into something and carving out a space. I may be misusing the phrase when I say I am building a cave-like structure, but this won't be the first time I've mixed my metaphors. I moved some text from a prior post to here to focus on the cave concept by itself.

Use of cement for the inside has also created problems with anchoring that go beyond weight. Cement shrinks as it sets, so the tendency for the piece to come out of the frame after it dries is great and requires additional anchoring, which adds to the complexity and amount of work required to make these frames secure. I have made a bunch of different test on anchoring techniques, but I have reduced my methods down to using thinner layers and the adhesive qualities of the materials themselves to minimize the risk of breakage in the frames.

The benefit of an inside surface that is made from a poured material is that I have been able to throw in a mold on the inside surface which provides a decorative element to the entire project. This could in fact be the best part about the bricks in that the outside layer is providing a shelter and the inside surface of cement is not only providing some insulating properties and fire protection, but is a photo fresco design on it's own. The inside layer could be a relief of a company logo or a relief pattern that repeats inside the wall like the brick pattern.

The inside layer is now where my focus of design is on and where I feel my hack artistic skills can be applied. I haven't gotten the same smooth results with an inside layer that I can get with the original outside piece, but I like the rougher cave-like texture that I am getting by just pressing in a thin mold while the cement is setting. This could be perfected if I make the two parts separately and mount them together, but again, more cost and time to prepare. My current process is quick and as inexpensive as I can get without sacrificing on achieving the goal of a functional product.

I have always used the metaphor that some art, like that found on ancient vases or cave walls, is journalistic in nature. The information contained on things made in prior eras is transferred to new and different societies through these pieces. Most materials and information that is created by a society ends up in a trash heap or simply falls victim to the realities of weathering and time and they disappear. The hardened items like metals and monuments of stone last the longest. Occasionally something like a vase or statue is unearthed that was preserved as a result of having been buried or protected in a cave from the light and weather. Now I have my own way to build not only pieces that can go in caves, but the dome is sort of the cave itself and the inside walls are mine to design like engravings on a cave wall.

I would love to build one of these in the desert as soon as possible so that the weathering can start taking effect, because I really want to see how the panels how up under real conditions in different environments. The desert is a great place to test durability because of the intense heating and cooling, as well as the wind and abrasion from blowing sand. It would also be fun to build a curved dome structure where it freezes and snows, then one where it is humid and rains. Still I haven't worked on the sealing between the frames, but I'm not as worried about that as I probably should be.

Weight plays a big role in the design issues

These frames may look simple, but to get the weight down it's been a challenge of materials and skills. I remember learning that most of the weight that goes into a structure is used to make a structure stronger to carry it's own weight. As with a bridge that is built from steel, the combined weight of the steel is so great that two-thirds of the structure is to hold up the steel. A good comparison of modern techniques of bridge building would be the new Oakland Bridge design compared to the old Oakland Bridge design.

The new looking bridge required more elegant design skills and hi-tech materials even though it looks smaller and simpler. This is similar to what I think has gone into the frames that I am building. The new brick facade frames don't look much different than some of my earlier ones, but there has been huge jumps in technique, materials and even design to make the new ones lighter and more useful.

The biggest change has been about whether or not a cement back is required or not for the frames that are made with an epoxy gel coat. I have installed a few of the frames without a cement back and although they are approximately 3 pounds lighter, the cement provides a more stable backing for the epoxy. Earlier models were in the 10-15 pound range and would be difficult to use in a structure without additional external or vertical supports. I don't see any point in getting a 20" X 24" finished frame below the 8 pound level that I am currently although I know I could if I worked with more fiberglass reinforcement and removed the cement, or put some sort of foam backing, however these techniques would also increase the cost.

The rest of this post was moved to a the next post on cave building.

Two steps forward, no steps back.

Over the last couple of weeks I have moved towards bigger and better things, like dome structure. The real art to me is the frames themselves, but I haven't sold many of them separately, so a dome structure provides me with a way to use them. The frames shown above are an example of a lightweight waterproof rectangle that could be used as a piece of framed art by itself or tiled out and mounted together to build a bigger thing like a wall or dome. Here is an example of a bunch of the frames bolted together to form a curved structure.

Only one of the frames is made with a sealed brick fresco in this structure, the red one towards the left. This particular one is made with epoxy and cement or plaster and is heavy compared to the new ones shown above. The new ones are made with urethane resin and epoxy with some fiberglass cloth reinforcement. Although they are a lot lighter I am worried about the potential for the plastic materials to sag as they are exposed to heat from sunlight and think that they need some reinforcement to keep them flat.

The frames shown above are inset in the frame and although they are water tight, I am worried that pooling water could accelerate the break down of the epoxy, so I have a newer version that covers the entire panel with a brick veneer that I would use in a dome structure. The time required to make multiples of these panels is a function of how many molds I have and currently I am working with only one mold, so I can only make one frame a day. I need approximately 60 frames to get a decent sized structure done and I want to get it finished before it starts to rain, but 60 days for 60 frames seems like a long time. It's like I am making a structure so that I can build more of the same structures in it. Testing the model on the factory floor.

Urethane is the Goop of the Gods

Urethane is the Goop of the Gods. When God made Adam he used Urethane. How else would the clouds be able to stay in the sky? How else would the planets be able to float in the heavens? How else would the mountains stay connected to the earth? The obvious answer is a liberal use of urethane resin mixed one-to-one with pigments added as necessary. There are many different types of urethane, but I have been testing the urethane resin, the one the Gods use, to cast a few frame panels with a brick pattern for my screen house.

The idea here is that the urethane resin may bond to the aluminum frames better than the epoxy resin does. If this is true then I can use the urethane, with pigment, to make my brick frames and have a more water tight bond to the frame, thus saving me time and money from having to do additional work on applying veneers to the exterior of the frame house to protect and seal the shelter structure. I have also set up a few test with using the urethane as a glue sealant in between two clamped frames to see how well the bond is for construction of the structure. I haven't used epoxy for this because it takes too long to dry and I have avoided using polyester resin because it seems too brittle and smells too much.

My thinking is that I can mix a batch of urethane resin, 60-80 ounces at a time for doing molds of the brick pattern and at the same time use the extra and the splooge on the side walls of the mixing container to glue together a set of frames before I install them into a structure. I still may apply some sort of trim on top of the joints, but my hope is that the strength and small amount of flexibility of the urethane may be a more durable adhesive caulk than the store bought stuff.

My cost analysis suggest that the urethane is cheaper to use than the epoxy and potentially just as strong for the exterior shell once I add a decent amount of pigments into the mix, possibly even less flexible under heated conditions, which may prevent sag. I am estimated the cost of the urethane to be $10 per frame, not counting fiberglass cloth and pigment. The frames themselves cost approximately $12, so a combined estimate of $25 per frame is conservative, not counting labor. By using old frames I can save the $12, but there is some cost in cleaning them off, so I would round that down to $10 off, or $15 per frame using recycled frames.

The weight of one 20" X 24" frame is 2.5 lbs. I have done a weight comparison of epoxy filled frames and that adds approximately 2 more pounds. With a backing of plaster material to strengthen the epoxy a final weight of 8 lbs per frame is achieved. If the urethane does not sag as much as the epoxy then I may be able to get away without the plaster backing and that could put my finished weight at less than 5 lbs per frame. So to cover an 8 X 8 section with a frame wall the total weight would be around 30 frames which would weigh approximately 150 lbs. Without the resin and just by coating frames with a urethane I could build a structure of the same size weighing only 90-100 lbs with some finished framing and paint.

Assembly time of a structure could be as little as 2 hours - 4 hours depending on how much drilling would be required. I am sure this could be less with more than one person, but I am talking about casual building time which would allow time to drink coffee and admire the geometry while building. The total volume of a dismantled unit would be 48" X 24" X 20", not counting the wood trim, which means it could fit inside the trunk of a car, the back seat of a car or into two shopping carts in case you have an urban street lifestyle.

Many things never turn out to be as fantastic as you can imagine them to be.

Many things never turn out to be as fantastic as you can imagine them to be. This turns out to be true over and over again. Since my imagination is greater than my ability to make things it keeps me coming back. This can be said with my attempts to make a brick veneer. The first veneer cracked on the edges when I took it from the mold. the second veneer, the one that I backed with plaster, would not come from the mold and the third veneer was successfully removed from the mold, but it has small holes on the top surface that would need to be filled. The dimensions of the veneer are just a bit small and I will need to trim it to try and fit it together with some wood trim, but the reality just doesn't measure up to what I thought it would be. I still see no reason to quit, but I do feel that I will have to take my time and think this through a little better. I know if I use the new Urethane resin the piece will never come out of the mold. I am thinking of ways to build the mold into the design and avoid the destruction of piece after piece, but I haven't settled on a plan. I did purchase some red oak to imitate wood with the next mold.

Urethane Resin and a Whole New World

Finding something that works like epoxy or polyester resin, but is quicker and has some flexibility to work with has been an issue, until now. The something may be Urethane Resin for several reasons. In an earlier post I mentioned the way that urethane had bonded to my silicone rubber, or vice versa, but either way it was a mistake, but getting something to bond to silicon but the mistake may have been cloaked solution. Urethane resin appears to have a strong bonding effect and sets really quick, like 1-2 hours. It can be mixed with pigments, or tints, for bright colors and can be poured in silicone molds like epoxy. I have just started a series of test with Smooth-On Urethane resin that I purchased from Douglas and Sturgess in Richmond, CA and am trying it inside a variety of molds, as well as, a sealer to see if it bonds to my screen emulsion and plastisol ink residue that is in my screens. The idea that it would bond directly to silicon may be a bit too far, but epoxy will bond to the Urethane which means I can attached the Epoxy shingles I'm working on to the Urethane coated screens for the dome structures that I am working on. Worst case scenario is that I use the Urethane as a paint on the exposed part of the seams and potentially as a bonding agent between the screen frames that make up the structure. Testing 1, 2, 3.

A Screen, A Wall, A Dome, A Brick and a Veneer

If you saw a screen meet a wall on the street what do you think they might do together? They might hang out together. Now if you had a bunch of screens coming down the street and they met a wall how would they all hang out together. The metaphor isn't applicable except that I have a bunch of screens from my screen printing business and I needed to make a wall and covering to shelter my old Hopkins 4-color press that I have in my backyard for down and dirty screenprinting at home. I also dug out my old magazines on building Dome houses from the Sixties and thought of different ways to connect my frames in the same way that the Dome builders were using triangles. Surprisingly it worked quite well.

I did some experiments with nailing my wooden frames together, approximately 16" X 19", and attempts to make a matrix that would make a curve and that worked reasonably well. Then I worked on a more complex matrix by overlapping two curves and although it had potential I stopped before I went too far. Next I switched out the wooden frames for aluminum frames to work on the strength of an actual structure. With 4" bolts a drill and a wrench I was able to build a curved shelter that was very light and reasonably strong. The arc is made by each panel and with a strip of wood at each joint the frames are slanted about 10 degrees for each 24 inches. The height is approximately seven feet high and the covering shades around 8 feet of flooring. I haven't finished the sides, but have made it so that I can take out the panels individually and deal with other issues like sealing and finishing the structure before I worry about closing in the space.

The advantage of this structure is with the light weight aluminum and although I have a wide range of methods for sealing and finishing this sort of structure easily, I don't want to use the feather-like nature of the frame and screen matrix. There is also the art concept that is inherent to the silk screens since many of them are from other experiments and jobs with printing so there are designs already on the screens and ink residue that adds random color. Still the screens didn't break and the emulsion is a naturally made to resist water, so I am comfortable that the screens themselves won't breakdown under a normal amount of exposure to the sun and rain. The interesting part of the screen is the photo-fresco part and that is that I have developed many techniques, previously discussed for years here, that can turn these frames into individual art pieces with a high degree of resistance to weathering. However, if I cover the frames with a quick and cheap paneling or coating then the designer effect is loss and the weight on the structure starts to increase.

A young neighbor was checking out my adult play structure and asked if it leaked and I admitted willingly that it wasn't made to keep water out, yet. Then I showed her a picture from the magazine on dome houses and the people in the house were sitting around a bunch of cans and hanging plants to catch the water from the leaking domes. This shows a problem that the dome houses have as a result of the many joints and non-flat construction and that is sealing the beast, or as they named them living houses. Later in the magazines it became apparent that the builders resorted to standard tactics like spraying the roofs with foam and plastics that made a water-tight structure with some insulating properties. As much as I want my life to be easy, I just can't do that, it's degrading to have to cover a curved piece of construction with a foam like it is the undercarriage of a car. My favorite idea in the magazines was to cover a dome with records as shingles and let them bake onto the structure. I've got plenty of records so that sounds like fun.

As I pondered the methods of sealing the frames with the screen printing residue still on them I wandered around my yard and picked up weathered frames that I had covered with a wide range of coatings to see which ones were holding the best. Many of my wooden frames are rotten on the ends that have been sitting unprotected in the mud and leaves, which is a good indicator of what would happen if a structure goes unprotected for years. Some other frames were peeled where I applied latex paint on top of vinyl. Others were I used mixtures of polyester resin had cracked and could be chipped away. The frames that I had made with epoxy using the frame as a mold only, without the screen mesh, showed the most promise in that they weren't cracked as much as the ones that I had used cement in.

Over the years I have been using a brick motif as my texture and from all of these experiments the epoxy mixed with pigments has proven to be the most durable and flexible material of the readily available products on the market. Cost is an issue, but for creating a thin durable layer epoxy just can't be beat. The drawback is that epoxy doesn't directly bond well with the emulsions and vinyl inks that are loaded in my screens. If I make a screen just for use in a structure, then I lose the recycling aspect of this project, however, I do gain much more flexibility in the overall design since I wouldn't be working with frames that have been used for print jobs before. The scenario that would be easiest to implement would be to simply coat the screens inside and out with a sealant that bonds to the ink and emulsion that is already in the screen and then connect the frames with bolts and seal the cracks with a flexible sealant that bonds to the aluminum. This isn't much different than spraying a coating of foam on the inside of a structure,and it would not provide any significant insulating effects. Cleaning my screens is my least favorite job, which is why I have so many screens to begin with, but the loaded screens with ink and emulsion doesn't feel much different than a gloried tent.

My instincts say that a truly finished product will require a screen to be completely cleared of the emulsion and ink before I start the job of making a newish screen structure. Purchasing new screens is almost as economical as the time, chemicals and labor involved with cleaning the old ones and there is no order to the designs that are on the old screens, so I don't think there is a real application of the old screens with designs unless they are covered and coated as previously discussed. Still, they are frames and could find a use as a test structure in the desert. I must accept here that the advantages of new screens are greater than the cost of the old screens except in the case of coating them and filling them with material that seals in the ink and residue.

One mold screen I found was a relief brick pattern that I made using the photo-fresco techniques and the inside section was the brick pattern made with an FGR / Forton MG plaster acrylic mixture, or possibly with regular Tufstone plaster. It seemed to be holding up well and the back layer was textured from the plaster enough that I felt an acrylic paint would cover it nicely. The weight of this piece was intriguing and when I compare it to the cement pieces there is a huge difference, yet both of them appear to be brick-like. As I held this particular frame I realized that all of the benefits of the screen printing frames are in the weight and all of the elements of the techniques are in the relief made inside the frame. Capturing these two elements into a usable frame is the essence of this project and finding a way not to have to put a heavy sealant layer may be the key to the uniqueness of this project.

The brick pattern has been repeating itself, literally, in most of this work and I came back to that here with the idea of epoxy laminates of the brick pattern as the outer shell on the frames. I can't cast both sides at once and I am very entranced by one side being an actual screen fresco made with either a plaster hybrid material or even an epoxy or polyester resin that conveys a design on the inside structure of the frame house, so I must adhere, paint or mount a sealant on the exterior to help keep water from getting inside.

Over the last two months I have been making epoxy stickers which are very thin and yet durable, so I went back to my old brick molds and poured a batch of epoxy into the molds to create a brick epoxy veneer that can be layered on top of the exterior shell on the flat part of the screens. I haven't figured out how to overlap the panels or how to seal the cracks between the screens, but this does create an exterior shell that also has a relief pattern that duplicates the pattern on the inside. The thickness of the epoxy will determine the weight of the final screen, but for a durability covering beyond just painting and sealing this should do the trick. The final cost of screen panels will also be determined by the thickness of the epoxy. I added a large amount of iron oxide to create a yellow brick effect and these pigments should allow the epoxy to withstand exposure to uv rays from sunshine.

I know this post is long, but unless I keep this together it will appear as one item on top of the other, so I will continue the explanation of Screen House construction with photo fresco techniques. The image in the image is important, the weight, durability, 3-dimensional texture and durability for exterior weathering. Each aspect of these variables limits the others to some degree. I envision a house that can be carried and built by one person in an afternoon and potentially taken apart and or modified as needed. One area that is not mentioned above in my list of variables is insulation and whether or not my materials will keep in heat or not. The final use of this type of structure may cause it to be modified, but the biggest problem I see is that the frames may get really hot in the sun and the epoxy could become flexible and release if it isn't mounted securely in the heat.

The top barrier and seams will probably get covered with wood trim, which will reduce the amount of heat that transmits through the aluminum frame, but the top layer on the screens themselves will transmit or reflect heat and cold depending on the materials. I also envision that the frames themselves could be solar panels, or work like a simple refrigeration system, but these methods would require testing and materials that are beyond my budget for now. I am currently making thin brick pattern veneers that will cover the backside of the screen panel with the inside of the screen facing inwards towards the interior of the space. If the pieces are connected from the top down then the veneer will have to work around the bolts, but if I move those connections inside then I won't have to worry about sealing a new hole from weathering. This leaves the seams between each panel as the most difficult to seal. Theoretically I want the structure to be able to come apart, so a rubber gasket may be the best bet for keeping water out. The problem with making a seal versus using a strong glue is that complexity usually takes time and creates other problems. For now I am going to assume the seams will get caulked or will allow water to pass through, but the answer is the more permanent the structure can be made when it is built then the more protection it will provide to leaking. Portability will create complexities that may increase cost and leakage.

During the casting of the epoxy brick veneers, or shingles, I have used two types of epoxy and in one sample I added a thin layer of Tufstone gypsum acrylic plaster with fibers to the interior to flatten out the back side and provide some strength. Generally the flexibility of the epoxy could be a positive, so the plaster will remove that characteristic that makes the veneers that I have been making seem more durable than the thin items I've made with other materials like polyester resin, cements, thin set mortars and plasters. I have recently learned of a urethane resin made by Smooth-On that sets in such a way that it can capture bubbles and other details. I'm planning a trip to Douglas and Sturgess to get a sample of this resin and see if it has any uses on the project. Epoxy does take a long time to set up, but the quicker polyester resins can't be made this thin and smell too much. This may be an alternative to both of these depending on how susceptible to cracking the new resin is.

I have also started test with a wide range of materials on the emulsion and through the screen to see which has the most bonding potential that can also be adhered to the epoxy panels. The problem is that time is the best test and I'm very impatient. I can hardly wait for stuff to dry before I want to test it. Still, if I can figure out what is in the emulsions that I use, minus the photo sensitive part, then I should be close to knowing what will bond with the nylon strands that make up a screen. I know there are fillers on the market and more and less durable emulsions that are made to stay in place on the screens I use for thousands of prints, but nothing is made to be permanent and these emulsions can be broken down with the right chemicals.