the Walnut Diary

I’ve noticed a lot of Google searches for parging mix turning up on my blog, so here it is:

9 sand: 4 mortar mix: 1 seal bond

That help?  I didn’t think so.  If you put nine shovelfuls of sand on top of four of mortar mix and 1 of seal bond, then add water, you’ll get a mess in your mixer that won’t do anything but rotate in a large, ugly ball.

So I’ll go back and try to explain this from the ground up.

Take a sturdy trailer to a quarry and buy a yard of masonry sand.  My 6 X 4 has handled many of these trips, but be aware that a trailer of that size heaped with dry sand has an additional weight of about 3400 pounds.  Exercise moderation when the guy poises the loader over your trailer.  1’ in the bottom is a good place to start if it’s a strong trailer, 6” if it’s a wide lightweight.  Be sure to have a shovel along to adjust the weight distribution so that it tows properly.

Leave the sand on the trailer.  You’ll waste a lot less and you can move it much closer to the worksite if you can get it out of there afterwards.  Position the mixer within easy working distance of the trailer, but high enough you can dump cleanly into your wheelbarrow.

Come up with a way to store your cement products so that they don’t get wet.  A second wheelbarrow and a nearby garage for overnight work well.

Everybody and his dog has his own way to make mortar.  I’m sure many of them are better than mine, but I’ll tell you what eventually worked out for four tons or so of the stuff.  If the sand and the mixer are dry, mix up the batch dry, then add water.  This hardly ever happens in the real world, so I won’t dwell on it.

Dump four shovelfuls of sand, wet or dry (don’t worry about the cat tracks, no big deal – it all mixes)  into the empty mixer.  If there’s water in it from rinsing out the last batch, no biggie.  Turn on the mixer and add a shovelful or two of mortar mix.  By mortar mix, I don’t mean that instant stuff like Sackrete.  I mean mortar in powder form intended to mix with sand.  Add water and let it mix.  Then add a shovelful of sealbond, a clay mixture known by a bewildering variety of trade names.  It makes the mix buttery, sticky, and easier to handle on a vertical surface.  Gradually add four more sand and one or two of mortar.  From there you go by feel.  Does it look right?  Did the last batch go on too gritty?  Too sticky?  Too dry?  It’s never right, eh?  Keep adjusting until you don’t care anymore.

If it looks perfect while mixing it probably means half of the mix is still dry in the bottom of the drum.  Ideally the mix as it gets buttery should roll off the top of the rotating drum and smoothly join the stuff at the bottom.  This takes a lot of practice.  By the time I had learned how to do that, the job was done, as usual.

Many times I have dumped the completed mix into the wheelbarrow, only to have to shovel it back into the drum because half of it was still powder.  That’s o.k. though it’s best if you don’t have an audience right then.  It mixes a lot better the second time.

The wheelbarrow is an amazing invention capable of allowing a worker to move two hundred pounds of slop over uneven ground to a destination.  Needless to say the physics involved, combined with fatigue, produce some spectacular spills, so it’s wise not to have anything breakable around the wheelbarrow route.

The delightful thing about the wheelbarrow is that, if you can get the thing up the stairs to the main floor of the building receiving the parging, it works very well as a storage bin for the mortar until you load it onto your hod.  There’s plenty in a batch to keep the parger busy for a useful amount of time, as well.

The problem comes when the job moves up to the second floor.  Now I know why those old stone houses had such low ceilings upstairs:  less wall to parge.

Faced with this problem I borrowed a gin pole from my pal Tom.  This rig is a small derrick which mounts on the corner of a conventional scaffolding unit.  It swings freely and has a pulley about 16” out from its axis.  After much fussing I devised a method to pull a 5 gallon pail full of mortar up to the second floor (3^rd level of scaffolding), then swing it onto a plywood platform perched between the scaffold and the window sill where it would sit until I dashed upstairs to rescue it before it fell.

This was satisfyingly complex, but too much work.  Eventually I simply filled two five gallon pails, grabbed them, and ran up the stairs.  Two pails were actually easier to lift than a single because they balanced well.  As I got used to it, the weight wasn’t all that bad, and with ten gallons of mortar per trip, I didn’t have to go up and down stairs all that much.

I have found that masonry is among the most serene work in the renovation.  Enjoy your mortar:  from here on in the project will only get worse.

For other articles in this series check:
https://rodcroskery.wordpress.com/category/renovating-a-stone-house/