Hypertufa Troughs

Saint Bonifacius, MN(Zone 4a)

A few tidbits of advice for those already familiar with the process:

Of course, anything could be used as a form: metal pails, plastic tubs, ice cream pails, sand forms, pans, pots, etc. Cardboard boxes are not strong enough. All but one trough in the photo is made with traditional wood frames. To keep the hypertufa from sticking to the wood, I don't use the traditional oiling or vaseline on them anymore. Using plastic bags is so much easier. You need to be careful when packing the hypertufa, so no bag creases indent into the hypertufa walls. That would cause weaks spots in the final product. My favorite texturing tools are paint scrapers and a grill brush. One scraper is flat like a puddy knife, but stiffer, and therefore does the job better. The other, an inside corner scraper, for making “deep gouges.”

Notice in the photo that the troughs are diferent shades of gray. That is because I used black cement coloring in the hypertufa, and at varying amounts. My advice here is: if you think you have added enough coloring, you need more. Remember that the hypertufa lightens up a LOT more than just a few shades as it dries and cures.

If you are using fibers instead of a chicken wire armature for added strength (most people are nowadays), mix them in with the dry ingredients first. They will spread apart and mix easier.

Do not pre moisten the peat.

Ever since I started looking in on the hypertufa forum on GW, I am finding that people are skipping what I consider a basic step in hypertufa making with peat. I discovered this when I kept reading how people mist their final products for days to “slow” the curing process.

It is certainly true, that the slower hypertufa cures, the stronger it will ultimately be. But misting simply replaces water as the peat in the hypertufa absorbs it, and isn’t slowing the process. In fact, the need for misting proves that not enough water was added to begin with, and in my mind produces a would be weaker product. Add enough water at the start, mix well, then go have a cup of coffee for 15-20 minutes. The peat will continue to absorb water. When you come back, adjust the consistency if needed, make your trough, and bag it to slow the curing.

This is not so crucial in more southerly locations. However in areas like Minnesota, where temperatures fluctuate drastically above and below freezing, structural integrety is foremost. A hypertufa maker(who mists) from California couldn’t believe I still have a hypertufa trough that has endured 20 years of Minnesota winters. All I am saying is, build it right the first time.

Additions, corrections, questions and queries invited.

Rick

Thumbnail by Leftwood
North East England, United Kingdom(Zone 8a)

Excellent - but where to put them all!

St. John's, NL(Zone 5b)

If the peat continues to absorb water, creating the need to mist during curing, why not pre-moisten the peat before using it? I'm trying to remember if I pre-moisten when I made my troughs but honestly can't remember. I used pro-mix rather than peat...pretty much the same idea. I cured mine in a plastic bag for about 2 months. Only once did I feel the need to mist the trough.

Saint Bonifacius, MN(Zone 4a)

Quoting:
If the peat continues to absorb water, creating the need to mist during curing, why not pre-moisten the peat before using it?

Of course, the need for misting is prompted by insufficient moisture in the mix at the start. That could include premoistening, but this is why I think it dry peat is the best way:

First, even with only slightly moistened peat, the risk of clumping even a few sphagnum fibers together is a real, and probable. When fibers are not completely coated with the portland cement in dry mixing, how can you expect the strongest hypertufa possible? This is also a reason why cement strengthening fibers are mixed in dry.

(Oh, and I am assuming that bailed peat is put through a sieve to separate out large pieces.)

Second, the property of dry peat that sucks water inside the fiber will also bring cement into tighter contact with the fiber. In theory, the cement will become part of the fiber itself, filling (or at least partly filling) the tiny crevices in each fiber. Now that's one strong peat fiber! Logically, I don't see that happening with such tenacity in premoisten peat.

Third, if misting is needed after forming the trough, yes the peat is absorbing water and "sucking" it in. But not so much the cement. The cement has already begun curing and is hardly fluid, compared to the way it was in the initial mixing.

Your right that pro-mix is essentially pre sieved peat and a wetting agent. Out of the bag it is already premoistened. Drying the pro-mix produces hard clumps. And fluffing it first, and then drying produces tiny, hard clumps. I don't see an option here with pro-mix. I think you will have to use it moist out of the bag. What you would normally end up with is a coarser textured hppertufa, with larger air spaces, once the peat decomposes away.

However pro-mix is pre sieved quite finely (finer than my screening), and mitigates the outcome. With your 5 feet of snow, I venture that your troughs are subjected to less stress than mine that are subjected to cycles of freeze and thaw, with and without snow throughout the winter. I am guessing the pro-mix debate is a wash.

As everyone should know, hypertufa is not an exact science. A myriad of ingredients can be used, and every recipe is workable. But some are better in certain situations than others.

Rick

Westford, MA(Zone 5b)

I took a class by Joyce Fingerut at New England WildFlower society. She has a book on making these troughs. See my review in the Bookworm section. One thing that should be emphasized every time hypertufa is mentioned that is that safety precautions need to be taken when working around the materials used to make the troughs. You need to wear an approved mask (not just one of those cheap disposable ones) and eye protection when mixing the dry ingredients. Also you must wear heavy rubber gloves to protect your hands when molding and mixing the cement. I do see these things in the FAQ over in the Hypertufa forum. This is very good!

In our class taught by Joyce, we used the pink insulation board (1" thick) and nails to make a frame putting the whole thing on a sturdy piece of plywood. So this is easy method if people don't have access to saws to cut pieces of wood. The pink insulation board is easy to cut (with an exacto knife) and the nails are easy to put it together. I wish I had taken pictures during my class to show the process. The pink insulation board has a coating so the mixture doesn't stick. We wrapped the whole thing in clear plastic while it cured at home. After taking it out, you can pull apart the frame easily and it can be reused multiple times. It is also easy to store as you can store it flat.

These are some ideas to add to above ideas which are excellent!

Saint Bonifacius, MN(Zone 4a)

I never thought that insulation board would be strong enough. That's Wonderful!

And yes, protection is important. Although I have never used any golves heavier than the disposable kind. Me bad, I guess.

Westford, MA(Zone 5b)

Leftwood - The instructor had us wear the kitchen dishwashing weight gloves. She thought these were best since they go up your arm too. I guess if the others hold up for you they are probably ok. All that is important is to protect your skin coming into direct contact with wet cement.

I wish the cement came in smaller bags than 80 lbs. Supposedly there are smaller bags of portland cement available but I have never found any. I would like to do another project but am turned off by the size bag of cement! Our class BTW had 12 people and used the whole bag of cement.

Sue

somewhere, PA

Sue,

A friend of mine buys the stepping stone kits so she can get small quantities of cement.
You might look for that. (I don't know how much more expensive it is that way though).

Tam

Westford, MA(Zone 5b)

Thanks Tammy for the idea. I often see these kits in the craft stores I go to. I'll have to check out the prices/quantities next time I go. I just wonder if the cement companies realize how many smaller bags they could sell! Even a 40 lb bag would be much more manageble.

Sue

somewhere, PA

i agree! You have to spend hours in the grocery store to figure out exactly which product of the 100's of
choices is the one you want but the marketing guys in the cement business just haven't figured out how to
market their product to the average consumer! Reasonable sized packaging.

Tam

Saint Bonifacius, MN(Zone 4a)

Well, their average consumer is not a hypertufa maker, that's for sure. We definitely are an untapped market, but I think they have their typical consumer pegged pretty well.

somewhere, PA

Oh so you don't think there are millions of us just waiting to be able to buy smaller amounts of cement to make
hypertuffa troughs? LOL

Saint Bonifacius, MN(Zone 4a)

Well Tammy, maybe we should consult the Hypertufa Society, the Economic Cement User's Association, the Potmaker's Guild and the Group for the Wise Use of Cement. lolx2

Westford, MA(Zone 5b)

Theoretically it is available in smaller bags. See this at Quikrete:

http://www.quikrete.com/catalog/PortlandCement.html

Just the stores don't stock it. It is hard to believe with food and consumer products you can get every variation under the sun but with something like cement there is limited choices. I bet someone could package some cement and the ingredients in a 'Make your own Hypertufa Planter' kit like the one for stepping stones and it would do well.

Seward, AK

Leftwood, don't forget the ICLWB-JHBS ("I Can't Lift a Whole Bag - Just a Half Bag Society")!

Westford, MA(Zone 5b)

So here's some info on the stepping stone kits. Michael's Craft store had the kits as well as the cement separately in 8 lb boxes. On the cement box, the package specified that it was a mix of portland cement and some sand. So I don't know how much sand is in the package with the portland cement. It was priced $5.99 for the 8 lbs however Michael's has coupons availalbe for 40 to 50% off that you can cut from the store flyer. So $3 may work for smaller projects.

Michaels Craft Stores
http://www.michaels.com/art/online/home

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