Rendering Q

[stefi]

I would like to get couple of opinions how to protect corners before rendering. For the price we got quoted 2800AUD (for about 100m2) options are eather aluminium eather plastic.

Which one to chose and why?

Thanks in advance,

Stefi

[john_unitex]

Aluminum oxidizes, so technically, it rusts. Plastic will expand/contract in varying temperatures.

This means that if you choose the Aluminum, you chance rust coming through your render.

If you choose plastic the render could potentially crack due to the expansion/contraction.

The best angle to use is a grade 304 stainless steel angle (same type of steel as your kitchen sink). This will not rust or crack your render. It is a little more expensive then your current option, but you will never have to worry about them.

Ask your renderer if they can get the stainless steel angles and how much extra they are.

[stefi]

Thanks John, looks like there is only one option left, and that would be SS.

Stefi

[rmartens]

External render?
I can't understand why you would want to put any external angle bead on exterior work.
Render is pretty hard anyway and better without any external angle bead even the expensive one if you are close to the ocean you will get problems and moisture has a chance to get behind the render. Don't put any external angle bead on exterior work you are better off. It will crack next to the bead. External sand finish render should be a ratio 5/1/1 thats quite hard remember if you hit a corner very hard that has a bead, you will need to replace and repair the whole corner lots of work opossed to just patching the part you hit. Rendering done properly and bullnosed is very good most people dont hit walls.

[pawnhead]

I'd agree with that.
I haven't seen them used that often, unless it was internal 'hard set' plaster work. I'd imagine that they may want to use them because it's easier than using straight edges, and bull nosing the corners.

[OBBob]

I have never rendered but I was looking out of interest at a new place near me that is just being prepared for render. They have put a plaster external angle on the corner. These are new subdivided townhouses ... so I'm guessing this is the cheap dodgy option?

[Tubby2]

I think this question is similar to 'which way to lay decking board? groves up or down'
I decided to employ someone to render my retaining wall at the front of my house. A guy by the name of John Ward. Appaerntly he's been rendering for decades and has never used any angles on the corners. As said before he think thats it weakens the edges.

The same week I noticed a neighbours wall being rendered and it had metal angles on it.

If I were to have a crack at rendering I would use them more so to use as a guide and run a straight edge off.

Slightly off topic but how do these guys make rendering look so easy?

[rmartens]

I have done work with angle beads on interior work for people and builders who want me to use them. If there are a lot of angle finishing is easier but they have their negatives. A good setting trowel cost around $100 and only used for plaster. When you run your trowel along an angle bead to obtain a tight finish, the trowel wears in the middle so when you try to trowel in an internal, you cant seem to make all the work smooth because the middle of the trowel is hollow. So what I try to do is use an old trowel on the beads. So meaning setting plaster on beads wears your expensive tools unevenly. For years I have been trying to get the perfect bullnose hand finished to resemble machine finish. When you do a good job with a hand finished external bullnose and look down along it looking consistent. With external angle beads I started using nylon anchors that way if its not quite level you can hit the nail one way to make true. So you drill a 5mm or 6.5mm hole, bang in a nylon anchor if its not quite against the straight edge hit the nail sideways till it touches the straight edge Doing this I have been able to achieve acurate beading. Im sure plenty people have seen beading not put up very well. Problem likes no mortar in the brick joints so how can you get a fixing?
(Slightly off topic but how do these guys make rendering look so easy?)
[COLOR="Navy"] It wasnt easy to start off with but in time and experience by the time we finish our apprentice and then years after that it becomes second nature like anything I guess.
I think the reason angle beads were introduced because too many plasterers did not do a good job. A good plasterer does not need to use beading and the job internal external will look good. Its time and money. It takes longer to set up beads in the first coat but easier in the finish coat.

[rmartens]

A nasty thing happened to me the beginning of this week. My small setting trowel is razor sharp as I was cleaning it my hand slipped running the outside of my thumb along the trowel. Im not happy as I cut my thumb oooh blood everywhere. Cleaned it up the plumber had a first aid kitput on antiseptic and a good bandaide. Replaced the bandage beginning of each day. Knitted well. After that I always wore a glove to wash tools and carefull and slow. I filed the end of my trowel to make less sharp and sanded the ends.
Once every five six years I cut myself on my tools not a good thing. I have come to the conclusion when you rush thats when you have accidents for me anyway.

[pawnhead]

if its not quite against the straight edge hit the nail sideways till it touches the straight edge Doing this I have been able to achieve acurate beading..

That's a good trick that I've used on plasterboard ex angle before.
I haven't done much cement rendering at all apart from a few small areas. There's certainly a knack to it, and I'd probably make a mess of it if I tackled a big wall.