I am having amajor problem with my hardshell scenery. I built the frame for the mountain, covered it with wire screen and began covering it with plaster soaked paper. I tried newspaper first, removed it and tried the brown craft paper like you would wrap a package for shipping in. That didn’t work so I tried paper towels as suggested. Today, I removed it. All 3 times the paper has dried and fell off the screen. The hydrocal ends up as dust collecting on the layout. What am I doing wrong. I have 3 scenery books and none of them explain hardshell scenery except to say you can do it to save from buying plaster cloth. Is this just that old of a technique that its not covered at all? How thick should the mix be? I make it kinda watery. Should I thicken it? I am asking cause I have wasted have a thing of hydrocal and have gotten nowhere.
As I was reading your problem I was thinking you have a bad batch or are mixing it improperly. Yes, try thickening it. You might even try just mixing up a small batch then soaking the paper towels(I like them because they absorb better, although I have a lot of newspaper soaked on my layout) and just give it about a half hour. The consistency I like is about like not quite as thick as oatmeal as if it were being cooked. In other words, it should be thin enough to be absorbed but not so thin it drips off of the paper too much. Although you will have some small amount of drip.
I used window screen (aluminum works better than fibreglass) supported by wood to create scenic landforms, too, but put the plaster directly onto the screen using a wide putty knife. This forces some of the plaster into the screen, ensuring a strong bond (I used Durabond 90 patching plaster, with a 90 minute setting time, so very little hardens before it’s in place). This saves the cost of paper towels and isn’t as messy. Before the plaster has set, I use a cheap 2" or 3" brush, liberally dipped in water, to smooth away any inappropriate marks in the damp plaster.
After the plaster has fully cured, I colour it using thinned flat interior latex house paint. This is much easier to apply, soaks into the plaster somewhat, and gives much better mileage from a gallon of paint. I found that a 33%-50% water-to-paint ratio worked well.
I recently moved the grain elevator, shown below, closer to the front edge of the layout, and needed a hammer to “re-grade” the building site [swg] :
After bashing down the bumps, I applied some fresh Durabond atop the smashed pieces still clinging to the screen, then pressed the elevator’s foundation into the wet plaster. The adjoining farm supply store was then added, and the scenery touched-up.
I usually use regular plaster when I made my mountains and just mixed the plaster to the thickness of pancake batter.
I was using newspapers cut into strips and just dipped the paper into the plaster mix and then slapped it on the screen.
I had covered my screen with full size news papers to keep the plaster from dripping through the screen as I used the chicken wire type of screen. I would wet down the full size newspapers to they would conform to the chicken wire screen.
Once the plaster set up I would then go back and paint on another coat of plaster (with an old paint brush) as this would thicken up the layers and smooth out the many layers of newspapers strips.
I almost sounds like the hydrocal is bad as it should get rock hard and not turn to powder!
I would go with Wayne’s suggestions. I didn’t use hardshell, but used Joe Fugate’s ground goop that has fine vermiculite and Portland Cement mixed in with the plaster of Paris. That combo of fine mesh and toothy goop worked wonders for me.
The very few times I resorted to plaster cloth strip from Woodland Scenics (first layout), I just dipped the strips for a full second, no longer, in a baking pan with tap water in it. Quck dunk, spread over the area to be covered, and let it dry. Later, overspray with water and apply a second layer, but cross-ways this time. In each application, the plaster barely had time to get wet with the second-long dunking, so it was more muddy when I laid the strips in place. So, maybe you should lay the strips over the mesh and then glop (paint, pour, throw) a much thicker mix of your plaster over the cloth while it is in place. Hey, it’s a thought…and free.
Have you priced out rolls of casting plaster at a medical supply center? You might be surprised.
Would you consider using J Cloths instead of the paper? That might help. I would have thought kitchen quality paper towels would do well, but…
I would guess that none of the plaster is oozing through the holes in the screen which is what would hold it on. Try spraying the screen with soapy water before putting the plaster coated medium over. That might help the plaster to ooze through the screen and get a grip on it.
The other thing I could think of would be to make certain there is enough plaster on the bottom side of the first layer of paper to allow oozing.
Of course my final comment is rather off topic. I have not used hardshell since I discovered foam in 1995 or so. I just cut, carve, grind the foam into the shape I want, paint and I’m done. I’ve gotten much better results too. The only thing I use plaster for anymore is rock formations that get placed on top of the foam. Foam is so much easier to mount trees, shrubs, and other things in too.
Here is a picture I just used in another thread. The module on the left has hard shell scenery and real rock, while the canyon on the right is all foam except for a couple of rock moldings (the really light colored tan).
Ok, it sounds from what you guys have posted that maybe I am not making it thick enough. I poured some of what was left in a rubber rock mold and it is still soupy after 36 hours. I used a consistancy close to milk. The paper towel was just getting wet I guess. I am gonna give it another try tonight and mix it thicker than before. If it don’t work, guess I am looking for the plaster cloth.
I use sheet rock joint compound. Dilute it to a consistency of about thick syrup. Take your newsprint paper strips of about 2 to 3 inch wide and dip it in the joint compound so that both side are covered. Then lay in on your screen wire.
One question: " are you using the plastic screen or aluminum. I used aluminum and it works fine. You can pick up scrap aluminum screen wire from glass companies. Those that repair glass and screens.
I am using the aluminum screen. Got a good deal when a hardware store went out of business. I am trying cardboard strips on another area just to see how that method works as well. More trial and error now than anything else. One question though, I added some powder tempera paint to the mix to color it some. Could that have an effect on the setup of the plaster?
Hydrocal goes bad over time if it absorbs water from non-airtight storage. It sounds to me like you are also mixing it very thin.
I would suggest that you take a disposable plastic container and do a test. Mix the plaster very thickly to say yogurt consistency. See how long it takes to set and how much strength is in the final set. It should give off heat as it sets and in 20-35 minutes, it should set into a chunk that is hard as stone.
If it doesn’t do this, toss it and buy a fresh bag at the local building supply that carries lathe and plaster supplies - 50Lb bag is around $30.00 - much cheaper that Wood land Scenics. To keep it fresh longer, I store my plaster in tightly sealed 5 gallon buckets (OSH or HD).
Hardshell scenery was originally designed to go over a scenery web made of cardboard strips. Hydracal is a form of cement and is very hard when it sets up. This combination was self supporting.
The lightweight hydracal that Woodland Scenics offers in the yellow, white, and black box is not the same type that was made popular back in the 1980’s known as the hardshell scenery technique and may not work for it.
The mix for hydracal made by Portland Cement is 50/50. One cup of water to one cup of plaster.
I don’t know what the difference between Hydrocal and cement is but I took a $3.00 50LB. bag of Ready Mix Cement and sifted the rocks out of it with the wife’s kitchen strainer. I then mixed it so it would not run at all. I then slapped it on metal screening and smoothed it and shaped it with my hands and a paint scraper. It looks great and I haven’t even painted it yet.
On another part of the layout I used Plaster of Paris and dipped ripped up sheets and Tea Towels in it and laid it over cardboard weave. That was for the rolling hills bit. Painted it brown, sprinkled real (sifted) dirt on it, and then static grass. I think it also looks great.
My wife is a Veterinary Surgeon. She brings me home their expired Plaster Casting material to use on the layout. A box full is sitting on the shelf as I find it really messy compared to mixing my own plaster of Paris and using 2’ x 2’ sheet squares.
Of course foam is my first weapon of choice. It looks the most realistic by a long shot, in my opinion.
So what is the difference between Hydrocal and Cement??? Is it worth the difference in price?
The mixture I use is pancake batter or maybe a touch thinner.
I also use paper towels dipped in regular plaster of paris over cardboard strip/webbing forms. I add dry cement pigments to the plaster to give it a color so chips aren’t white. Be careful though, that pigment can make it too dark easily.
I use cut up paper hand towels like you see in a public restroom. Also, to mix the
Finally to speed things up, I use two halves of a cheap basketball. I cut it in half, and use both insides as mixing bowls. This allows me to work on a second batch without cleanup, and clean up is easy. I let the plaster dry, roll up the basketball and the dried plaster falls out. THen just a quick wipe with damp towel, and i’m ready for the next batch. Wish it was my idea. Got it from a forum or mag.
Mixed up soupy batch of hydrocal and used paper towels cut into strips. Placed these over my screen scenery forms and worked it in tomake sure some went through the screen to get a good adherence. Well this evening, 18 hours later, I just pealed off over 3/4 of it. I mixed up a batch of plaster of paris and used the same technique in a different area and it dried hard and formed up well. So I think that left the belief that the hydrocal went bad. It dried hard but just crumbled up. I contacted Woodland Scenics and was advised that the lightweight hydrocal isn’t really designed for use in hardshell scenery. It is more for rock molds and the such. So, tonight I go back and re-do the same area for a 4th time.
And I thought wiring was supposed to be the frustrating part.
Cement is a coarser product and made for construction. Hydrocal is a plaster product thus is smoother. It just happens to be made by a cement company and is very hard. I had to buy mine in a 50 pound bag.
Adding color to plaster can affect the setting. If it is turning to powder, it has gone bad. Also you are working too hard, use foam and coat with plaster cloth (can be had cheap at art stores like ASW).
Don’t have an affordable source for foam around here except the white styro. I broke down and bought a roll of the plaster cloth last night at Hobby Lobby and tried it. Man I can’t believe how easy it was to use, but the cost makes it impossible. The roll only did about 5% of what I have. The plaster of paris and paper towel area I did it still solid so it looks like that is how I need to go. A 25lb bag is only $10 and paper towels are cheap.
Plaster cloth is about as clean and easy as you can get for covering lots of acreage but the Woodland Scenics product is indeed cost prohibitive. I got a box two or three cubic feet in size stuffed solid with plaster gauze off of Ebay for about the cost of three packages of the WS stuff.
Now having a huge supply of plaster cloth available to use, I swear by the stuff (instead of swearing at it).
