Making a damned mess of mortar!!

[andrewpreece]

Very good advice to which I would add:-

Get a bricklaying trowel ( they're quite big ) Get a surface on which you can "butter up" the mortar ( it needs a little working by the trowel when you first pick it up, to loosen it up and turn it into a "sausage", by scooping it up with the side of the trowel and turning it over and over in a sausage shape ) As suggested, put a zigzag pattern on the mortar you lay before the brick goes on; this is to allow you to adjust the height of the brick by introducing airspaces. If you lay the brick on a flat bed of mortar, you will be able to tap it down only by squeezing mortar out of the joints; this will only work for small adjustments, if you keep tapping the flat bed of mortar will sieze solid, and you'll have to take the brick off and start again with new mortar.

Also, did you use plasticiser in the mix? Another thing which I would like others to comment on, is the use of "soft" sand for mortar ( doesn't feel gritty, small rounded particles, usually golden brown in colour ). I have always used fairly gritty silver sand ( it seems to be de riguer in my locale ), but I'm sure it doesn't help the properties of mortar or the ease of spreading it.

IMHO bricklaying is genuinely difficult, and there is no one thing or tip that makes it easier, only a host of techniques and tools and experience ( e.g. getting the mix consistency right is absolutely fundamental )

Andy

[al]

Ok, I got a ready-to-mix small bag of brikie's mortar today to put together a small (3 bricks high) border wall around a flowerbed. Mixed together the soft sand and cement just like it said and added water.

This is where it all started to go wrong. I made my little volcano and poured the water into the middle. Then I flopped in the dry mix from the outside and wondered what to do next!! Basically landed up mixing it around with my hands (was in a wheelbarrow) and forming more volcanoes and adding more water until I thought it wouldn't crumble apart.

I started laying this down on the concrete base and pressing bricks into it. I couldn't get it to stick the side of the brick (vertical joint) though with the second brick. I think I put too much water in then as it was a little runny. It still wouldn't really stick to the bricks though. Tried using the trowel to flatten down the mortar underneath the bricks I was doing, but it didn't really seem to help much and I landed up using my hands to pat it down as much as anything else - especially in the joints.

My question is, where did I go so wrong!? It would appear I'm crap at mixing it as I don't really know what it's meant to be like and I'm especially crap at laying it! Now I'm not completely handicapped in that I'm alright at woodwork and metalwork and general DIY. This seems to have been a poor first outing for cement mixing though :o(

a

[Edrich]

Hello Al

Perhaps someone else can give you advice on laying bricks. I just wanted to warn you that concrete or mortar on bare skin can cause burning which can be quite serious. My advice is not to come into contact if you can avoid it and if you do wash it off as quickly as possible.

Edrich

[al]

Thanks for the warning. I did wear latex gloves, however I discovered at the end of it all (about an hour in contact) that my thumb had gone right through!! Did wash thoroughly after though. Why does it burn? Is it because it contains lime? Does it only react with some people or is it bad for everyone?

a

[Bob Minchin]

The mortar should be quite wet and creamy but not sloppy. running a shovel over the top surface and making some vertical stabs into the pile. The pattern should remain but the depressions should not fill with water. Your bricks should be bone dry. You want he bricks to initially draw the water from the mortar (called suction by the Pros) to stick the mortar on the ends of the bricks (buttering).

Layout a line of mortar about 3" wide and two and half bricks long. Run the trowel along the topof the line wiggling the trowelfrom side to side to create a grove down the middle like a capital M in section. the peaks should be about an inch tall. Gently place your first brick down on top of the M and tap gently down with the end of the trowel handle until the brick is level and with a mortar joint about 3/8 in wide. Excess motar will have flowed into the middle of the M and a little will have squeezed out of the long sides of the brick joint (snots). Hold the trowel blade horizontal and with a single upward cutting action pick up the excess from each side. and slide this off the trowel onto the end of the line of exposed mortar. Butter then end of the brick with fresh wet mortarand lay the second brick against the first gently tapping downwards and VERY genttly toward the first brick to close the buttered joint. And so on. Don't try and fiddle about with the joints. If you have got it wrong. take the brick off, slice the mortar off, stirit back in with the rest, and have another go. Once you have placed a brick don't go back to it to adjust. This will just give zero strength joints and end in tears.

After an hour or so, take a joint rubbing tool or a short length of 15mm copper pipe or even a bit of garden hose ans rub the joints to give a curved recess. do the verticals first then the horizontals. The mortar will be dry enough to crumble into a dust. Discard this.

Easily written but needs practice. I suggest you buy a bag of building sand, mix this with some water and a splash of washing up liquid as a plasticiser. NO cement yet. Practice laying dry bricks. this mix will behave very similarly to real mortar and allow you to experience suction. and do the pointing up. Once you have had enough of this, take it down and put the sand back into the bag, wash the bricks and allow to dry in the sun. Even if you are full of confidence then dont use the wet bricks until another day.

Despite any temptation, never touch the motar with your hands only the trowel. Mortar on the hand gets transferred to the bricks and then thye get stained etc etc.

Hope this helps

When you can lay a couple of hundred an hour you will be getting the hang of bricklaying!!

Bob

[David W.E. Roberts]

Good tip! My bricklaying is up there with my soldering :-)

Cheers Dave R

[al]

Thanks both of you for the excellent advice. I shall practice away before I try building up any further! Mind you, chances are when what I've done dries out, I'll land up hammering the crappy mix of mortar I made off the bricks to start again!

One more question though with relation to mixing the actual ingredients - what's the best way to do it? I laid a plastic sheet down in my wheelbarrow and mixed it all in there, using the sheet to toss it over on itself as well as me mixing with my hands. I then just took lumps of it up on my trowel to apply to the bricks (generally fell off!). I know a cement mixer is ideal, but I must be missing something here for small amounts - it has to be easier than the way I did it!?

a

[Bob Minchin]

Mix up on a piece of plywood or similar about 4 foot square. Mix dry ingredients first then heap into a pile and make a central hole and pour in a little water,daming any leaks. mix in the water (no hands!) and put back into a heap and repeat. Most cement or ready mix will have a plasticiser included. Check on the bag. If you need to add your own, washing up liquid is fine. Use about twice as much as if you were washing up and have a bucket of water with this mixed ready before you start mixing the mortar. remembe to put the washing up liquid back in the kitchen - It drives my missus up the wall when she can't find it in the kitchen cupboard! You can get a plastic mixing tray with a raised edge to retain any spills etc if that helps. When you have a nice smooth creamy pile of mortar. Transfer a bucket full onto another piece of plywood about 2 foot square placed on a pile of bricks at about the height you are working. Another tip. Use two bucket of the same size. Keep one dry and only use for measuring cement. The other can be used for measuring sand or any other 'wet' job.

I expect to see some photos of the completed project by close of play Monday !!

Good Luck

Bob

[stuart noble]

I think you need a builder's bucket and a stick

[Simon Avery]

Hello Jeremy

Makes it more "workable" - ie, it's less crumbly, more plastic. Smoothes easier, can retard setting (depending on type), aids adhesiveness (depends on type).

Lots of proprietry types that do all sorts of extra things, and PVA is widely used as a plasticiser as well as a waterproofer and adhesive additive, and there's the home-brew versions like washing up liquid and urine. WUL can cause bubbles though, which weaken the mortar so isn't recommended. Neither's Urine, unless you're onsite and there's nowhere else to go...

[Jeremy C B Nicoll]

Thanks to those who replied!

[al]

Was in work all day today and suspect local builders merchants will be closed tomorrow, so not a lot of chance of that I'm afraid! Mind you, Wickes might be open and they're not too far away ...

I do have two 70 foot fences and one 30 foot fence (both sides) to stain though. Something which I think could take quite some time .......!

a

[The Natural Philosopher]

Well yes, it does tend to turn the oils in yer hands to soaps, and make your hands all wrionkly, but heck, its not that dangerous except in your eyes.

Tricks are firsts of all to make the mortar stiffish. so it doesn';t slump. And sticks. Then you lay it in a little pake and tap the bricks dwon with a runnver hammer or teh ned of teh trowel.

If teh bricks are ultra porous, they turn the mortar from creamy to wet-sandy in seconds. Soak em first.

As far as getting teh mortra to stick to the end faces goes. its a hard one to get right. If it fails don't despair. spal some mortar over the top of teh crevice and use the edge of the trowel to ram it in - lots falls out, so pick it up with the trowel and repeat.Then opint it downwrads with teh trwoel tip to make a decent finsih.

When mortar is half goine off - 2-10 hours depending on temperature, use wire brushto get what's stuck on the brick faces off, and when its set use brick acid a wire brush and a hose to get the last residues off.

Structurally a brick wall is a jumble of bricks held together by their own weight, and prevented from slding past each other by the mortar beds. How you get the mortar in there, is down to personal preference.

Traditional bricklaying is all about how to do it EFFICIENTLY, but for us amateurs, any way will do as long as it gets in the cracks OK.

It takes a week or two to get the knack of whatever standard you decide is acceptable. A pro brikkie doesn't need to spend ages pointing up filling gaps and cleaning off afterwards. He lknows his mixes, consistencuies and materials and his tecdhnique is good. Yours won;t be, so expect to mess around with mixing (use the trowel to 'cut' the cement into the water etc, or hire a mixer), aim for a consistency that like mud, will stick when thrown, and throw it on teh bits you need it on, clesan off surpuls with teh trwole, and slap them bricks down. Bits of string and a spirit level help to get it square, and a wire brush and brick acid will make it look decent when done.

[The Natural Philosopher]

Urine is good, especially oin teh finished wall to encourage lichen growh and make it look settiled in and old.

I ALWAYS piss on my brickwork.

Yoghurt is good as well allegedly - about all its good for IMHO.

>

[stuart noble]

I think plasticisers are better than washing up liquid because they dry out to a solid which doesn't adversely affect the water resistance of the mortar. AFAIK Fairy Liquid never actually dries completely. For what they cost and the amount you need I can't see the point of gambling with a product designed for other purposes.

[stuart noble]

I agree. But for for "small" read a couple of drips to a bucket full of mortar. If you start getting bubbles you've overdone it.

[al]

"stuart noble"

Do you mix the whole lot in a bucket rather then heaping it up flat and mixing?

a

[chris French]

In message , al writes

Mixing mortar in a bucket is only practical for small quantities - a few trowel fulls - for a little bit of pointing, for filling a gap etc. I usually use a trowel to mix it up.

I note from your original post that you tried to mix is up in barrow - I suspect this is part of the problem. This isn't actually that easy - you can't get in with shovel at the right angle and I find it hard to get it mixed properly. I don't bother, I would just mix it up on a flat board.

Get a board about 4 foot sq. - Or I use one of those plastic mixing boards with a rim - it helps catch run off.

Mix up the materials dry, heap up, make the dip in the middle, pour in the water. Using a shovel pull into the middle. Once you've scooped it in then just get in the shovel and start turning it over - I normally work round the heap turning it into the middle as I go round. Stop occasionally to work through it with a vertical cutting motion with the end of the shovel.

don't bother from here trying to heap it up again, just splash in a bit more water as necessary and keep mixing to the right consistency (the last bit just really comes with practice)

[stuart noble]

I do. A black builders bucket and a garden spade is a good system for small amounts. Hold the bucket still with your feet (i.e. one either side!) and rotate the spade.