I have a block wall I would like to improve too. My wall is painted and has the old product I tried to cover it with 10 years ago on it so I do not think concrete would stick very well. My thought is to cover the wall (about 12 feet wide, 6 feet tall) with hardibackerboard - a concrete board 1/4 ich thick and I know concrete will stick to that perfectly.

I have made some leaf imprints and casts that I think are wonderful. I also make leaf imprints and casts that I really hate. I think that is what is stopping me from starting on this wall idea. I fear I would get 3 good ones done and then ruin the wall with ugly ones. One idea I have had is to stick copper tee connectors into the concrete as I cover the wall. Then I could do the same with leaves I cast and place them whereever I wanted on the wall afterwards and change them anytime I wanted.

Just some idea starters....
Laura

Belinda, I haven't really done any imprints on vertical surfaces now that I think about it. I have always put concrete on a leaf and then sort of "slapped" (not hard) it onto the surface..... this leaves 3-D effects instead of the indentation of an imprint. Even then, my surfaces have been balls so the curve helps hold the stuff on til it can dry. I am not sure I can think of a way right now to do either one on a vertical surface. I will think about it....
Maybe Dena or some of the others who have done lots of imprinting will be more helpful.
\Laura

I just had a thought. You could take 1/2 inch thick pieces of styrofoam cut into some size that made sense for your wall (maybe 8 by 8 inches) and - as you put the concrete on the wall - put these styrofoam pieces everywhere you would like a leaf imprint. The styrofoam just serves as a "space holder". When the wall is set, you pull out the styrofoam leaving 8 by 8 blank spaces.

Now you take the same size pieces of hardibackerboard which is 1/4 inch thick and you spread enough concrete on a piece to make it come out the thickness of the concrete you put on the whole wall. Now, you can make imprints into this concrete. When it all sets and cures a few days, you take the ones that came out great and place them in the "empty places" in your wall. You could then blend more concrete on the wall to obscure the 8 by 8 inch edges if you wanted.... or you could sort of make them more obvious or whatever design idea came to mind.
Laura
thanks for asking this question! I am getting ideas for my own wall

Quikwall is made to cover blocks. It has fortifier and bits of fibers in it already. You mix it up like a paste and spread onto dampened blocks. Now, how would I do your wall? I would take leaves that I like, put Quikwall onto the leaf and let it set up overnight, or how ever long it takes to make as many leaves as you need. Then, leave the leaf on to protect the surface, and start spreading a 3/8 in layer of Quikwall onto your blocks. You kind of have to smear the edges as you apply so it will stick, and it has to be paste like, not runny. After you cover a small area, stick in your leaf with the green leaf outside, showing. I wonder if it will slump? You may have to take a stick and prop that leaf into the wall to hold it up til the Quikwall sets up. Then when all is nice and set up, in say 3 or 4 days, you can peel off the leaves. Just a thought. BB

thanks everyone for your great responses. i wasn't clear on what i was trying to do. I want to get the look of fossilized leaves in the concrete. Would i cover the wall with concrete and then press the leaf into the concrete? How long would I leave it on and would i be able to use the leaf again or use a new one? What kind of concrete would i use? thanks bbb

BBB,
Depends on what sort of fossil you want, a print or a relief.
If a print is what you want you could do the following:
1) get some leaves that have heavy veins or ferns with sturdy fronds.
2) Dampen with a spritzer bottle or a hose (the hose will only work before the first print or relief is done) the area where you want the print.
3)mix up a slurry of cement sand and water/bonding agent, to pancake batter consistency. recipe 1cement:2sand
4) Using a cheap chip brush brush this mix on the area that you have dampened and applied bonding agent to. Have a squeegy ready to catch drips, or chip brush to splay the edges into the existing wall surface.
5) press your leaf or fern into the slurry. And step away. The leaf or fern should have stuck to the surface
6)A day later remove the leaf/fern or just let it decompose off the site. keep the area spritzed with water.
For a relief:
1) choose your leaves. Ferns are difficult to do a relief of.
2) dampen and paint(with bonding agent) the area to reliefed on your wall
3) mix up 1 part cement:3parts sand with enough water/bonding agent to make a thick but spredable mix. (Add your liquid slowly)
4) press this mix to the veiny side of the leaf, so that it is about 1/8-1/4" thick, dependent on how 'relieved' you want the leaf to be.
5) With a slap of the wrist, place the side of the leaf that has the mix on it onto the wall area that has been prepared. Neaten any edges that squish out from the leaf and onto the wall.
6) It should stick and you should be able to walk away.
7)A day later remove the leaf or just let it decompose off the site. keep the area spritzed with water for several days to assist in curing.
Hope that was easily understood.
Happy Fossilmaking,
Dena

Here's one more...Make plaster molds of the leaves (or whatever) you want. They will be "negatives". Then fill them with hard urethane rubber (these will be "positives"). Then you can use them to "stamp" negative leaf impressions anywhere you want them into the stucco or concrete mix. That's exactly how the pros make concrete stamps of various natural stone textures. The processes and material information can be found at either Reynold's Advanced Materials or Smooth-On's websites. You can do the same with sea shells, woodgrains and all kinds of stuff. Even dinosaur remains. And, best of all, they are reusable for other projects. Hmmmmm...maybe a Brontosaurus on the bottom of the pool...nah...make that a Plesiosaur...like Nessie.

Depends on what sort of fossil you want, a print or a relief.

Dena-

Imagine if you had negative tree trunk/branches shapes and positive leaves? (or is that the otherway around? I gets me negatives and positives mixed up.) I think that would look pretty cool.

Tah!

I like the possibilities of this. I have a small above ground plastic pond which I just haven't been able to decide how to disguise. I have been mulling over a mosaic surround for it but the amount of work has been putting me off. This fossil wall idea would probably look great, I wonder if I could try and use leaves that would look like they are meant to be underwater, and maybe some star fish , shells etc for an underwater theme.This doesn't sound like quite as much work as the mosaic idea, but would still look pretty good. Always great to get new ideas ,
Cindy

If you want a "positive" final imprint (one that is the same as the original), you can either make your "stamp" directly from the original (if it is durable enough)...or make an intermediate mold before making the final...which goes like this...
1. Make a plaster mold of the positive original (the mold will then be negative).
2. Make an intermediate casting from that mold in plaster or any hard casting material (this form will now be positive and can be touched up and detailed).
3. Pour a urethane "stamp" over the intermediate casting/form. The urethane stamp will now be negative which will produce a positive final impression in the material you press it onto.

Can get a little confusing, but just remember that the stamp you use must be the reverse of what you want the final impression to be. If you want a final image that is the same as the original...the stamp itself must be the reverse (negative) and versa visa. The advantage of using an intermediate is that you can clean up any details as you go. Working directly from an original is great when you can do it, but often problematic since you can't do any detailing directly to the stamp and the urethane, like most rubber molding materials, is extremely sensitive to the moisture and chemicals of the original, either of which can wreck the curing process. I've seen very nice direct urethane pours onto leaves and organic matter, but the originals had been dehydrated and thoroughly sealed first.

If you decide to get into "stamp" making, be advised that urethane rubber is available in many different densities. The "hardness" is rated on what they call the "Shore Scale" which currently runs from about 20 up to 90. The higher the number, the "harder" the rubber. For stamps used on something like concrete, a "Shore 90" (the hardest & most durable) is advisable. Also be advised that making stamps can be addictive because they are reusable and so versatile that you may find yourself wanting to cast everything you see. I hereby disclaim any reposibility for any neighborhood pets that turn up missing. Stamp responsibly.

Great tips Tango. I've recently been making molds with a more professional grade tin cure silicone rubber. Rather expensive, but the results can't be argued with. Your advice about the shore hardness for stamping is right on. I've found that it depends on the what your trying to stamp or mold to to use a correct shore hardness. If what you are stamping has no deep undercuts, the harder shore is better. However if what you want to stamp or mold has more detail or deep undercuts a softer shore hardness will work better for you.

Also if folks consider going this route there are different types of urethane available now too. There are ones that have a slicker (oily) finish that means you dont have to be as finicky about a release for your moldings. If you go with the dryer type urethanes you need to use a good release agent.

I'm going to do more experimenting with different types of silcone materials as I like the finished product and it'll last longer than urethane rubbers. I want to try the brush on type to reduce the amount needed to cover the model and then go with a backup shell of some material like fiberglass for longevity.

Is your neighborhood missing pets or squirrels maybe that can be posed in your Faux Bois trees? LOL :)

Muddy Medusa woman,
Tree trunk ideas. Several months ago I got interrupted in making a mold from a very detailed piece of tree trunk. I had coated it with at least two coats of 'inexpensive' latex mold maker material. Being sure to get all the crevices etc. I never got back to this but the outside of the piece of trunk is now coated with latex, and I have used it successfully as a stamp to impress bark design in fresh mix. The latex coated piece washes off pretty easily. I have also lined a plastic mold with bark pieces, the bark detail inward ( this can be sprayed with release if desired) then put in my tufa, or 'mortar' type mix. In about 24 hours the the form is released and the bark pieces are peeled off again to use over. So your idea of a tree is certainly do able.
Tango, I am still too chicken to buy what seems like expensive rubber mold making materials without having either eyes and hands on learning or exact names of products with Garden Web people to help me through it.
Stamps, skins and form liners are all of interest and present wonderful options. I was just at Seattle Pottery today and they will be having a mold making class, (not tile April) but it is on my Christmas wish list.
Good discussion going,
Dena

Hey Dena --- Don't know where you are, but check the Reynolds Advanced Materials website to see if they have a location anywhere nearby. Every location puts on several excellent 2-day training symposiums a year and they are well worth the $75 or so bucks they charge. Especially when you include the 50% off deal on supplies available to attendees (I'm guessing they still do that). I went to one in Dallas, Texas sevseral yers ago and can absolutely recommend it. Great & very knowledgable bunch of folks who very quickly covered basic and some more advanced techniques in plain English. No, I don't have any business relationship with them...I'm just a big fan and regular customer. It's both rare & pleasant to come across a big organization that actually delivers more than the opportunity to let you give them your money for a change.