OK,are you in my head or what!I was going to try hula hoops as well!!Even bought them but for what I need,thet're a bit too small.Septic tank covers are slightly larger,but your technique is spot on !I think I'll flatter you and copy what you describe.
BTW,another"hoop" possibility would be plastic waterline that's used for the inside of houses.Quite thick,would bend to form a circle,I think...
Cheers from here(but,you knew that!!)

Laura, what GREAT rocks! How much quikwall did you need to make them? One bag? More? Less?

Is the hula hoop still inside the large rock?

Love the picture of the guys standing on the rocks. What good sports they are. BTW, have you got them hooked on this yet and did you add in the weight of the wrench?

Rick; great idea about the plastic pipe! With a few strands of fishing line, you could deform it from a straight circle. Another thought for straight blocky rocks would be to heat and bend the pipe.

As for shaping; how about stuffing a plastic bag with scrap styrofoam? Once set-up; you could remove the styrofoam for reuse.

I still don't know what fiber is. I see that people use it a lot and would like to use some also if i knew what it was and where I can get it...

Laura - this is SO good, and the pictures are SO helpful!!!! It is too cold here now for such projects, but I have it earmarked for spring play!!!!!!

grins

Vicki

Vicki-for shame!We don't tell Easterners that it gets too cold out here in the NW!Why,just today,I contemplated swimming in our local warm lake...just kidding.They have better weather than we do...for the moment.Revenge is a dish best served in snowy conditions!!
cheers from here

Those rocks look great! You are quite the grand experimenter...wow! I gotta find some of that mesh. Filling a bag with styrofoam would make a good center. You could also use spray insulation foam to fill in spaces too.
-Carol

Rick, I discovered another substitute for the hula hoop. I dug/pulled up some old pvc 1 inch water pipe that I've had underground for 10 years (kind of an underground hose system). I was trying to break it by standing on it and pulling. Instead of the splintering I expected, it squeezed down and bent. I just bent it into a triangle and thought that would be a great rock "hula hoop" that isn't round. Haven't tried it yet (thus explaining why my yard looks so awful- lucky I have a small fenced in area I hide my concrete mess behind)
Laura

Fleur, yes- the hula hoop is still inside the big rock. I have to guess how much quickwall I used on the rocks. Less than 1 bag for sure. I used the Quickwall as the first layer. For the outside layer I used regular portland cement/fiber/sand/bonding agent. Since I used 2 products and didn't really keep track..... I don't have a trustworthy answer for you. However, I would guess 1 bag of Quickwall would have made both rocks. Maybe not since the bag weighs 50 pounds and I made 70 pounds of rocks........

Those guys on the rock were concrete workers who tore out and put in my new driveway (1700 square feet- gasp). They do it all day for a big company in town and hire out cheap (around here, five dollars$ a sq ft to dig out and put down new is a good price) to do it some more on their off days. They were wonderful to have around. I had no idea in the world how hard working concrete is. The big truck lets it trickle down that chute at some slow rate the men can deal with. They work like crazy wading in there with tall boots for an hour to get this all just right to suit them. Then the truck leaves and they use long tools to smooth it all out so it is perfectly level. Just when I assume they are finished (it looked good to me) they go eat lunch and let the concrete sit there 30 min and they come back and work 3 MORE HOURS with hand tools on the surface. With just 2 men working, they had to do the drive in 4 parts so it has taken forever but now it is done and I like it.
They were amazed at the stuff I was doing with concrete. They had no belief that the big rock would support them when they saw how I had made it. After they tried it (I didn't have the camera out for that one) they still were amazed - even brought another man by the next day to see it. It was fun to see the looks on their faces when they realized how strong the rocks were.
Laura

Rick - LOL - yes, I did screw up, didn't I!!!??

Laura - I have lots and LOTS of flexible pvc - purchased when I was making "hoop houses" w/ rebar, pvc, and bird netting to keep the deer out of my crops. It was long before I turned my eyes toward cement and such - and all those pieces of pvc are still here, waiting to be reemployed - oh boy oh boy oh boy!!!!

You rocks look great and the pictures sure explains what ya did. That Quickwall and mesh is neato stuff! It must be a double take for passerbys to see you totin your rocks around...lol (and that lady's done put one on a pole!)
Very cool.
Annie

That was linnea2 who put one on the pole, it's hoot thinkin bout people totin boulders and puttin em on poles..

Clairdo- the fibers we mention are the ones concrete companies (where they fill the big trucks that carry wet cement around to jobs) use in their mixes. To get mine, I followed a concrete truck "home" and went inside and talked with the people. They sold me (6 $) a sack (about the size of a quart size ziplock bag) of the fibers they use. This sack is tossed in a whole truck of wet cement to make fiber cement (I made that name up but you get the idea). This should last me a lifetime considering I mix concrete about 20 pounds at a time compared to up to 30, 000 pounds on a cement truck.

The other way to get fibers is to buy one of the many concrete dry mixes that have the word Fiber in their names. (be careful - some of these also have gravel instead of sand as the aggregate). Quickwall is the name of a product made by Quickcrete company. Quickwall has the fibers already in the dry mix.
Hope this helps.
Laura

Does anyone else think the fibers we buy by the bag resemble cut up clumps of the angel hair we see around Christmas?

Maybe this will help.
from: http://www.npc.com/products/fiber/concrete-fiber.htm
Quote: " Using fiber in your concrete is easy. Simply toss the premeasured bags into the concrete mixture - one bag per cubic yard of concrete - and allow 3 to 5 minutes for mixing. Additional water is not required even though concrete may appear stiffer. If a super-plasticizer is to be used, add and mix the fiber first."
So, it isn't a bag to the whole truck. It is a bag (depends on size of the bag this company was refering to) to a cubic yard.

And they are using NYLON fibers, not angel hair, which I believe is or used to be made of spun fiberglass. The fibers in Quikwall are more like one inch strands of thin yarn, and they are nylon in composition. I like using quickwall for this reason, on leaves and sculpting stuff.But when I added perlite to the ready-mixed Quikwall, it weakened the product. Hmmmm

I like those fake rocks, by the way. The hula hoop has had a comeback in another life!! That must be a very large rock. I have a roll of the plastic black tubing they put underground for water. That will work like hula hoop. More flexible than PVC, too. BB

BB, the hula hoop I made the rock on was a smaller-than-usual hoop. The rock is 32 by 34 by 24 inches tall.

Thanks for the fiber info.
Laura

Laura,
I am a little confused with your first explanation. You say that you put blac plastic over it so the mix would not fall through. So am I understanding that the bag is sandwiched some how, of it the wire ontop of the bag that is covering a harder surface?

Dena

Laura,

Those aren't rocks they're boulders! Great job!!! I'm the last person to be giving advice on anything structural, but I think it's a waste to have the wire armature and not have it IN the concrete. I can see it would be tough to get it to stick to something that big and not fall through, but maybe you could put the trashbag on the inside of the wire, fill it with sand (or anything you want), add the concrete, and then remove the "stuffing" after it cures. Just in case some jumbo concrete workers come by to hang out ob your rocks :)

regards, Justin

I usually use peat moss to bulk out shapes. So...you could make your wire shape, then put the black plastic bag inside the shape, and fill it with peat moss packed very tightly. When you'd made your boulder and it had set for a few days, undo the plastic bag and rake out the peat moss.

I'm sure someone has posted this link already on some thread or other here, but just in case anyone has missed it, here it is again. Lots of information that can be applied to hypertufa rock making.

Here is a link that might be useful: Fake Rock links

PS - a lot of those links are dead, but just persevere, the ones that are still working are worth browsing!

Laura,
I also think the wire mesh is just one more little structural addition.
I used plastic bags inside my wire mesh and the mesh eventually ended up inside the mix. If I had wanted to I could have gone back and neatened the inside of the rock, further enclosing the rock.
When I did the rock for the gunnera leaf, there was nothing to catch the 'drip through' pieces, so the 'liner' really does work.
Running dog, the peat moss definitely is lighter than using sand. I would think since the 'rock' in being made sometimes has to be repositioned that the Peat should be secured inside a bag for better reuse and less mess.
Nice Rock Laura,
Dena

Dena, to answer your first question, the only "hard" surface is the arching chickenwire. The plastic goes over that and the first layer of mesh and concrete (1/4 inch thick total) goes right on top of the plastic. That dries and layer 2 of mesh and concrete is added. Then the rock is done.
Laura

Running Dog - thanks for the great link. I haven't seen this before.
Laura

I want to write this message very carefully because it is exactly the kind of thing I want to explore on my topic. I want to "argue" (further discuss) a couple of ideas without dampening anyone's enthusiasm for offering suggestions. I am just as happy to find out I am wrong about an experiment as to find out I am right - I have learned just as much either way. so......

In my experience (1 rock), filling a bag with stuff to support the chickenwire armature for a rock resulted in a much thicker concrete covering because there was always some air space to fill in order to "reach" the bag and enclose the wire in concrete. I do see that some of the things suggested to use to stuff the bag sound better than what I used but I can't quite imagine that I could manage to construct something where the chickenwire laid absolutely flat against the supporting bag.

When you put the concrete/mesh right on the bag which is stretched over the wire, you can make the cement thickness (with the mesh) 1/4 inch for each layer. This is what results in the lightweight aspect of the rock. My goal is to be able to move the rocks without much help but to still have a rock that supports a lot of weight for safety reasons.

I agree that encasing the wire inside the concrete would make it stronger but I have given up that added strength since I think the other way is strong enough (holding 400 pounds) for the purpose of making a safe rock.

I would be happy to hear any thoughts as to where my thinking is wrong or how I could improve the idea.
Laura

Laura,
Do you then remove the chicken wire, or is it that the smaller rock just does not have any blackplastic or wire?
There is so many ways to work this.
Dena

Dena, the smaller rock was made on the form the big rock was later made on. When I put the mesh/concrete layers on about half way down over the wire and plastic form, I realized I could have a little rock if I just let it dry like that and removed it - which I did. Then I used the same wire/plastic form and made another bigger rock and left the wire/plastic form inside.
Laura

Laura, stick with what works for you. It looks to me like you really got a tough rock there! I was just offering another way of doing it. Keep up the great experiments!

Justin

ltd123 - I can see your reasoning, and as a female I always have the same concerns about making stuff light enough to move by myself. You could remove and re-use the netting once the rock has set, since it's not performing any structural function.

Laura, I just came across your great looking rocks while searching for suggestions to make my own large rocks. So expensive here in Florida and not easy to find. Your pictures and descriptions make me think I should go out tomorrow and start one. I was wondering if you have any recent pictures of your year-old rocks to show how they aged. Any moss, coloration, etc? Thanks so much for being so descriptive.

Ginny

Well I must say making fakes rock is somewhat fun. I didnt realize that it is not as hard as I thought it would be. I made a large boulder that is set over a sump with a fountian pump in a larger stone structure. My base stone was painted but didnt really get a good chance to set in before our rainy season here in Tennesse so I will need to repaint my base stone when it is dry enough. Here is link to my Walmart photo album hope you enjoy them.

Here is a link that might be useful: Fake Rock Pics

I'm new to the forum. While researching hypertufa today I found your posting Nov 2 05 for fake rock photos. This is exactly what I have been searching for. But I cannot find the photos. So my question is - how do I find your photos? Thanks.

I made some fake rocks and bolders--they are holding up well.
Click the link and scroll down to read the "HOW TO" and see my pic.

Thanks all, Radd

Here is a link that might be useful: How to make fake rocks and bolders

hi, could I ask if this is fish safe, and if not. what can I do to make it fish safe.thanks

I bought a bag of quickwall but what by do you mean by mesh. also, I take it that your garbage can is short enough so that the hula hoop rests on the ground while you are working? Thanks Connie

I'm so frustrated that I can't see the pictures of Laura's rocks!

I think this technique is exactly what I've been searching for. I want to make a couple of fake stone chairs that will be similar in shape to beanbag chairs, but with rock markings. I think the wire armature will work for me. I'll build it, then put something under it and sit on it to make the seat indentation! Then I'll add the quickcrete.

Based on reading lots of websites about hypertufa, I was thinking I'd have to make the concrete or tufa much thicker than you've made yours. Am I right in thinking it's the fibers in the initial layer of quickcrete that make your structure strong enough to hold 400 lbs w/o after the armature is removed?

Being almost 8 years late to the conversation, I am guessing the original poster will not be here to answer this, but is it possible that someone that saw the pictures Before they were removed can tell me:
Is the process being described here like 'paper mache' using plastic/fiberglass mesh (like used for screen door replacement) for the 'paper' and cement/concrete/quickwall for the 'paste'? If so, this could be a great for my current project as a hard 'shell' over the Styrofoam core.