Mortar Joint Repointing

[Tenacity]

Two in a day I must be related to a bus . So what is the best method of removing the old mortar before repointing these days, not by a hand chisel I hope! I have SDS machines so perhaps there's a specific chisel bit, or is there a specific power tool? Ooh whilst I'm on a run is there a clever way for repointing? There you are, 2 buses sorry questions at once, sorry I blame my age oh go on them I've always been daft and its not the most interesting of tasks.

 

[Rorschach]

Depends how difficult the old mortar is to remove really. Last job I did I could brush it out with my finger! lol

 

[Tenacity]

Depends how difficult the old mortar is to remove really. Last job I did I could brush it out with my finger! lol

mortar Ninja, think its gonna be a mixed bag and manicures are too expensive

 

[Mike.R]

Here are your weapons of choice,. A lump hammer, a scutch chisel and a plugging chisel.

How old is your property ? Is the pointing lime mortar ?

 

[Rorschach]

Here are your weapons of choice,. A lump hammer, a scutch chisel and a plugging chisel.

View attachment 117271

How old is your property ? Is the pointing lime mortar ?

Get those mushrooms ground off!

 

[jimmy_s]

I've been doing a fair bit of re-pointing this last week. I've been using a smallish dewalt battery SDS with a rotary stop and either a small chisel or a point. It will depend on what you are dealing with, I'm repointing roughly coursed ruble sandstone so the joints are quite wide in places.

Repointing with NHL3.5 lime with sharp sand.

 

[Tenacity]

OK I have 2 of those weapons, no scutch. The mortar looks bad and patchy but I haven't given it a prod yet. So I'll check it out more thoroughly, then, to save my ageing joints I'll probably use my mains SDS (lighter than battery machine) and by either a scutching bit or possibly one of those Bosch mortar knives but need to read up on the bosch

 

[mikej460]

For the looser stuff try a power hose, it might save a lot of time. I prefer a plug chisel for stone work or a grinder with a thick masonry disc on it for straight brick work.

 

[mikej460]

OK I have 2 of those weapons, no scutch. The mortar looks bad and patchy but I haven't given it a prod yet. So I'll check it out more thoroughly, then, to save my ageing joints I'll probably use my mains SDS (lighter than battery machine) and by either a scutching bit or possibly one of those Bosch mortar knives but need to read up on the bosch

Be careful you don't go too deep with the sds as it may loosen the bricks/stone

 

[Cabinetman]

The only time I’ve ever seen it done the Builder used a grinder as Mike J460 said, repointing, well I once tried one of those guns (Like you would use to apply silicon with but larger). Some people may be able to get them to work, consistency of the mortar is critical, but I found it to be much easier and quicker with a small trowel. Ian

 

[PerryGunn]

If you have an angle grinder a carbide mortar rake works very well - they look like this and throw off less dust than a grinding disc

Worth getting a tuck trowel as well, cheap and made for repointing - just hold mortar on the back face of a normal trowel and push into the joints with the tuck trowel

 

[pe2dave]

I'm sure there is a specific tool for this? Blade for an angle grinder, 'wide' disk meant for concrete?
Anyone?
E.g. this on Amazon

 

[PerryGunn]

I'm sure there is a specific tool for this? Blade for an angle grinder, 'wide' disk meant for concrete?
Anyone?
E.g. this on Amazon

The problem I've found with using angle grinder discs to remove mortar is that, unless you have a shroud with dust extraction, it throws out large plumes of abrasive dust that ends up everywhere - and neighbours can get a bit annoyed when it comes in through open windows or their cars end up covered in it.

The mortar rakes still produce the same amount of dust overall but, as the outer edge isn't spinning anywhere near as fast as a disc, they don't throw it out in a huge plume - the majority ends up around the base of the wall.

I'm not saying you can't use diamond discs in a grinder to remove mortar, I've just found that the mortar rakes are a much 'cleaner' way to do it - and I've put 'cleaner' in inverted commas because, however you do it using a grinder, it's a messy job.

 

[Tenacity]

Thanks all, watched a you tube video by Tibby Singh, he shows 4 different ways of doing it. His demo helps to decide what best suits me. Favourite would be the gun, 2 things put me off, the faff of filling the tube and waiting for pointing mix to go off enough to dress it. Thanks PerryGunn, learnt something new as didn't know what a tuck trowel is

 

[Rorschach]

Worth getting a tuck trowel as well, cheap and made for repointing - just hold mortar on the back face of a normal trowel and push into the joints with the tuck trowel

That's how I did mine, I never got the hang of picking up mortar on a normal pointing trowel and don't do enough bricky work to faff about trying to learn. I pick up some mortar on my bucket trowel and use it like a hawk up against the bricks then slide it into the joint with the tuck pointer. Might be slower than the proper way but it works well, I get mortar right to the back of the joint and the result is reasonably neat.

I use one of these (choose a suitable size for your joints, go one size under), just a couple of quid and works really well.

https://www.amazon.co.uk/R-S-T-Tuck...1&keywords=tuck+pointer&qid=1631008465&sr=8-6

 

[Tenacity]

That's how I did mine, I never got the hang of picking up mortar on a normal pointing trowel and don't do enough bricky work to faff about trying to learn. I pick up some mortar on my bucket trowel and use it like a hawk up against the bricks then slide it into the joint with the tuck pointer. Might be slower than the proper way but it works well, I get mortar right to the back of the joint and the result is reasonably neat.

I use one of these (choose a suitable size for your joints, go one size under), just a couple of quid and works really well.

https://www.amazon.co.uk/R-S-T-Tuck...1&keywords=tuck+pointer&qid=1631008465&sr=8-6

Looks good to me just need to survey area and check joint sizes

 

[Rorschach]

Looks good to me just need to survey area and check joint sizes

I cut myself a bit of stick to use as a gauge and tested the joints, easier than measuring, I am pretty sure the 3/8" is what I ended up buying as the majority of joints were in the 10-12mm range. It doesn't have to be an exact fit as you can tilt the blade to get it into tighter gaps etc.

 

[MARK.B.]

Done a fair bit of pointing over the years and apart from a stiff finger i have lived to tell the tale. personally i would avoid using a SDS drill or mini breaker as you are likely to do more harm than good. A angle grinder works well with the right cutting disks and those carbide mortar rakes work fairly well,but you have to be careful as one slip can not only ruin your brickwork and will almost certainly ruin your day if it bites you. When doing large areas i prefer to use a point master,once set up with the right mix they are quick and easy to use and squirt the mortar right to the back of the joint. Ideally you will need to rake out around 20mm or 3/4". Take a bit of time to clean out the joints with a brush or airline.
When mixing your mortar try to get your ingredients the same for each mix or it may look awful when dry and all different shades. Use a spray bottle to dampen the joints before filling,this helps to prevent the dry brickwork and remaining old mortar from sucking out the moisture from your mix. Be mindful that you do not leave to long a time after filling the joint before you go back and finish an area, in warmer weather it will dry out and be difficult to get a good finish.
Last pointing job i did was for my mate Bob,an old village school converted to a house,took 8 weeks from start to finish and it was a pig of a job that I was glad to see the back of it .

 

[Noho12C]

Repointed half of our double garage few months ago as the mortar was getting loose in some areas.
Used cold chisels and mallet to remove the old bits. Took a while and fairly noisy. If I had to redo it, I would buy an angle grinder and suitable bits to remove the mortar. Still noisy but much faster I believe.
To put the new mortar, I used a trowel and pointing trowel, plus a truck pointing and brick jointer to have a nice finish. Not too long and I think you can get an efficient workflow pretty quickly. And found it fun to be honest

 

[mikej460]

I cut myself a bit of stick to use as a gauge and tested the joints, easier than measuring, I am pretty sure the 3/8" is what I ended up buying as the majority of joints were in the 10-12mm range. It doesn't have to be an exact fit as you can tilt the blade to get it into tighter gaps etc.

Whilst I was repointing our old stone cottage an old boy in our village told me he was taught to point lime mortar into stone work using a suitably fashioned stick so he made one for me. It was a stick version of the modern one above and worked well but didn't last as long.