Removing render, lime mostly, some cement. Suggestions for a lightweight but powerful tool?

[saveasteading]

We are finding that the removal of hard render is proving very slow and hard work. Most is lime, some of that is rather hard and may have some cement in it, and some is clearly cement and has to come off.

Then we can repoint and repair as necessary.

 

It is a job up on a scaffold and tiring with arms up. The breaking tools we have are very heavy and more appropriate to downwards work.

Also they create a lot of judder and noise , whereas a better tool will put the power more efficiently into the scabbling/breaking job.

 

A borrowed Hilti is performing better than the owned 'Wickes' one, as would  be expected, but has to go back. But even that is quite heavy for prolonged periods.

 

Any recommendations please? Ignore cost if necessary, if it is good enough to save many days of torture.

 

 

Another query. We are well aware of the need to use lime in old masonry walls, and now also of the ' breathing' reason for this.

However does the logic apply in any way to an internal  face, which will be hidden behind an inner insulated and vapour barriered,  stud panel. There are relatively small areas of patch repair in cement mortar, but still some hours of bashing and perhaps masonry repair afterwards.

i.e, the outer granite wall gets wet and then breathes it back through the lime. It is unlikely to be wet past the first thickness of stone (200 or so, of 600). Even then, the evaporation should be outwards not inwards.

 

 

 

 

[Conor]

I'd reccomend a cordless SDS drill, rather than a full blown kango type SDS max machine. something around 2-3kg would do the job. I've a brushless Makita one and it's one of the best tools I've ever used. You'll need at least two batteries though, not cheap.

 

https://www.toolstop.co.uk/makita-dhr242z-18v-cordless-li-ion-sds-plus-brushless-3-mode-rotary-hammer-drill-24mm-body-only-p67795/?gclid=CjwKCAjw9-KTBhBcEiwAr19ig48OgjUqC_KZYP28rK6y06msef8fERqFHYN4MoLjZ_xDdKu9LWJgaBoC1dMQAvD_BwE

 

I also have a large titan sds machine and now rarely use it as the Makita can do 90% the same work but far lighter and a lot less tiring. The titan is now only used for core drilling

 

 

Edited May 9, 2022 by Conor

[SimonD]

I agree with @Conor. I have a cordless Bosch Professional that's been impressive. The other option if you have a compressor is to use an air hammer - so light you can hold with one hand and can be bought dead cheap. I used an air hammer to remove concrete render from the back of my house and to remove all the existing plaster inside. The only limitation with an air hammer is the width of the chisel attachment but you can get some up to 75mm which I believe Sealey sells for one of its hammers.

[saveasteading]

Thanks both. we have started on the deWalt trail so should try to continue that for battery consistency, all other aspects being equal. 2.5kg seems the lightest and that is before battery. They also have one that looks smaller but must be very long as it is 3kg+......but I wonder if that could be supported on a shoulder strap.

Air was my first thought some months ago but I have never used one. The kit is cheap and light and we have a  cylinder already (can't think why). If they are that light then they will also be easier to use at an angle and get behind the render. I'm sure a 75mm chisel is plenty....perhaps a thinner one will be better for getting into the joint between stones, ie behind the face a bit.

[Simplysimon]

also with air you can get a needle gun for smaller stubborn areas

[Roger440]

I did most of mine with a needle gun. Air powered, so quite light. A trelawney one. Had it years, great piece of kit and can just get away with a 1.5hp portable compressor.

 

Damaged the surface of the bricks a bit, but the prying the plaster off was doing the same as they were very soft.

 

As it was being replastered, not really a problem

[saveasteading]

we have a 2hp compressor, so perhaps worth a try. Do the £50 tools from Draper or Erbauer do the job, or does it need something fancier?

We don't have any concerns about damaging the granite masonry. Getting the cement mortar unstuck (10mm thick, and more in the joints is the issue.

[gaz_moose]

all the cheap air hammers will be about the same, i would just buy a £20 one and see how it manages the task. they are very air hungry so remember to stop often to let your compressor catch up/cool down. squirting a drop of oil down the air inlet hole at the start of every day should help to keep it alive.

[SimonD]

I always use an air hammer with an inline lubricator. Bear in mind also that the cheaper models tend to have a lower maximum pressure. I've wrecked a few purely due to connecting them straight to a compressor outlet running at 8-10bar for nailing and then the air hammer mechanism jams in short order. The Erbauer air hammer IIRC needs max 6bar pressure and will work fine for what you need.