G'day Slate --- Rebar (reo?) can be welded with either. I personally prefer my little MIG because it keeps the heat low and the head is small enough to fit into really tight spots. Overheating rebar can cause it to crystalize to the point it will shatter like glass when bent or hammered, so proceed with caution. As far as attaching the stucco lath (expanded metal), even though it can be welded by turning the amperage down to almost zero, you are better off tying it on with with either galvanized wire or stainless steel "safety wire". It's quicker & more secure. The safety wire is normally used to secure nuts & bolts on aircraft, racecars and motorcyles, so those are the folks I'd look to as suppliers. While you're talking to them, you might also see if they carry "safety wire pliers". They are designed in such a way that they make twisting the wire as easy as giving them a pull. Very handy. Learned that trick way back in my formula motorcyle racing days...never knew I'd be using them to create art with later.

Regarding expanded metal lath...galvanized is what plaserer's have used for nearly a hundred years and is more than adequate. It will get surface rust almost immediately once concrete comes into contact with it, but the surface rust is actually what protects it. It will eventually degrade, but because it's mass is so relatively small, it's not a problem unless it is very close to the surface. Besides, it's only real purpose is to hold the concrete in place until it sets. Like rebar, it should be embedded at least a half to 3/4's of an inch below the surface to prevent "shadowing" ( a slight discoloration that often appears where metal is close to the surface).

Iwill try one more time to post the link to my Album page, but can't promise it's working (having fits with it lately). If it is, then take a look. Several Albums have quite a few pix of welded frameworks & completed armatures.

Best of luck mate. Hope this helps a bit.

Here is a link that might be useful: Armatures...if the %#@! Link is Working

Hi Slate-

I just finished a rockwork class that was geared towards professionals and semi-pros, so professional techniques were emphasized.

Whenever we created the armatures for fake rocks and rock facades, the rebar was always tied with a long length of tie wire (just like you can get at builder's supply houses) that was then doubled up by bending it together, then the doubled wire was wrapped around the two pieces of rebar to be connected and tightened with pliers twisting the wire ends together.

Also, care was taken to keep 1/2" to 3/4" distance between the rebar and the lath or chicken wire that was being attached to the rebar. This was so that the rebar would be completely embedded in the concrete or shotcrete.

All of the things we were creating had to be up to structural code, so if your project isn't being offered to a government entity, you probably can get away with lesser strictures.

BTW, shotcrete is FUN, but the hose weighs a TON. Never worked so hard in my life and I was paying the teacher to work me like a dog. Go figure.;D

Tah!
Jo

MMW --- Boy...we sure hope you have pix of the class in action. Shotcrete is a process I'm itching to give a try. Had a friend who built a lot of sets & movie props out of the lightweight mix. Sounds excellent...who put it on?

There was a Dinosaur Mini Golf in Ontario with several huge shotcrete boulders. The armatures for them were CARS direct from a wrecking lot.
Real cars with engines out but tires intact. They towed in the cars flattened the tires and shotcretted them.

Outstanding!!! Kinda' gives a whole new spin to the Chevy tagline...
..."Like a rock", doesn't it?

TANGO, thanks for the info I was after. Yes, it was very helpful. You ever been to Australia? Or are you just familiar with the lingo? I really appreciate the assistance
you give, you wouldn't believe how hard it is to source materials and Info here. Maybe it'll get easier as I dig in
a bit more. Everything seems to be geared to standard applications here. Maybe that's a good sign, cause if I
ever get to produce pieces the way I want them to be, (quality), then maybe people will look and say, Wow! look at that!
MMW, thanks for the input on armatures, wish I could do a
course like that here!!!
Everyone is so secretive about the processes used in the
making of things unusual in my locale.
Thanks again guys,
Slate

Slate --- Sorry t'say I never made down under. The aircraft carrier I was on was scheduled for stops there on three seperate occasions and we were all pumped for it. And, every time something happened and we were directed back to Yankee Station in the Tonkin Gulf. Met a lot of really great Aussie blokes in Viet Nam and discovered that Texans & Australians are like twins that were seperated at birth.

Glad to help with the info but sorry to hear the concrete folks there are apparently as tightlipped as the ones here. Sourcing reliable info seems to difficult everywhere. While you can find a great deal of info, especially online, it is nearly all geared to commercial production requirements and engineered to meet very specific and narrow design criteria. Mining and deciphering the data to uncover what is applicable to your specific needs is the tough part. Just remember that there is no such thing as a "Best Way"...without first determining what it is that you want to accomplish. You have to try and analyze their data from the standpoint of what specific problem a given formulation or process was designed to address, then try and figure out what benefit it might provide your projects. It's a lot of work and you will nearly always get blank stares and contradicting information from the "experts", but stick with it, experiment, filter out what will work for you, and eventually...you'll be your own expert. Hopefully one that will be willing to teach and share their knowledge.

Best o'luck mate. Still hoping to make it down your way someday.

I know this is kind of off topic for hypertufa, but HT would also work for most of the following.....

>MMW --- Boy...we sure hope you have pix of the class in action. Shotcrete is a process I'm itching to give a try. Had a friend who built a lot of sets & movie props out of the lightweight mix. Sounds excellent...who put it on?

The class was through the "Workforce Training" center at a local vocational-technical turned community college here in Albuquerque. The WTC trains folks to work in construction, beauty salons, auto shops, your basic vo-tech output. The site we worked at is owned by the county and they were paying Desi to bring up classes to enhance the site, an old tuberculosis sanitorium near Albuquerque, NM.

The teacher, named is Desi Brown, has about 20 years experience in fake rock work and has spent most of his time working at the local zoo, botanic gardens and for the city making rock facades here and there. My plan over the next month or so is to collect some photos of all of his stuff to post in an album which will include some pics I have of the class. Desi is getting out of the rock making game and into teaching, hence his foray into teaching techniques of rock making.

Desi was very generous in offering recipes, experience in making press pads and molds of various rock surfaces, and his time in explaining what works and what doesn't work.

We made, textured, carved and stained faux rocks and vines in addition to shotcreting additional rocks and vines. We learned to bend and tie rebar armatures, wire in lath/chicken wire subarmatures.

Shotcrete is a fairly involved (and expensive) process. You need a cement truck (you need several yards of cement to make shotcreting worthwhile), a compressor/pump, alot of shotcrete hose and several nozzles just to start. It's not something you can do by yourself or even with one or two other folks. We shotcreted 10 yards of cement creating half a dozen large (boulder sized) rocks, steps, walkways, vines. We also used the shotcrete to backfill behind some molds of rockfaces that we had created in an earlier class and mounted throughout the landscape.

It was a great experience and I learned alot about working with cement that can be applied to HT. I'll have to see about succinctly putting a review together.

Make some friends of contractors and see if they'll let you come along or observe a shotcrete session. It's way cool and a great way to get alot of cement distributed in a relatively short time.

BTW, our shotcrete recipe was 10 yards of "10 bag" cement, which works out to 940 lbs of portland per yard or 9400 lbs total. Whew.

Desi recommends using lime if you are working on vertical surfaces and to make the cement stickier. I have a list of his recipes somewhere. I'll dig them out for you later.

If you want to see what shotcrete can do, go to your local zoo and look at the habitats for various critters, 'specially outdoors. I'd bet that they are mostly shotcreted.

Tah for now.
Jo

Jo lime is cool unless you get it on your skin. YeeOuch!
I use it when freeforming up hill. It sticks and doesn't slump as much.
The more lime the weaker the recipe. It ceases to be concrete and becomes mortar.
It can also make your projects more toxic for some plants.
At least in the short term.

Jo,
would love to see Photos of Desi's classes, and especially his method and recipes, for construction, and texturing/shaping the rock. PLEASE say you will post them!
Thanks for the info so far. I know that recipes and techniques aren't the be-all and end-all for works in any field, but for those who are unfamiliar with the principles thru experience, they are at least a starting point, where there was no starting point at all.
Hope you're all having as good weather as we are here, middle of winter and frost in the morning, and up to 23degC in the middle of the day. Thats about 68deg F.
Adios,
Slate

MMW --- Thank you for the info. Sounds like a really great program put on by knowledgeable people.