Tools for cutting slates.

[epsilonGreedy]

I need to buy one or more tools for cutting natural slates, think mine are a typical 4mm to 5mm thick.

 

The guy behind the Restoration Couple on YouTube used a handheld slate cutter that looks like a pair of giant scissors and also a slate guillotine. Depending on how much of the roof I tackle there is potential for 500+ cuts. There will be 250 half size gutter perimeter slates alone plus multiple angled cuts for a valley and hips.

 

Just wondering if folks have any experience of these?

 

https://www.amazon.co.uk/gp/product/B00SEI2ZJY

 

In action here at 45 seconds https://www.youtube.com/watch?v=9L75DmSYwiU

 

 

 

 

Or...

 

https://www.aboutroofing.com/heavy-duty-roof-slate-guillotine.html

 

[SteamyTea]

Angle grinder and a diamond disk.

Cheap, quick and easy.

[markc]

Slate knife and shear post give the best results but difficult to master. Angle grinder is fool proof but does leave a hard cut edge where the knife is more blended and subtle

[epsilonGreedy]

3 hours ago, markc said:

Slate knife and shear post give the best results but difficult to master. Angle grinder is fool proof but does leave a hard cut edge where the knife is more blended and subtle

 

 

Thanks this gives me a third option.

[epsilonGreedy]

3 hours ago, SteamyTea said:

Angle grinder and a diamond disk.

Cheap, quick and easy.

 

 

I will keep one of these on hand as a fallback when the classic slate cutting options fail. The gutter perimeter slates might be doable with a grinder because the clean disk cut edge will be under the first full slate.

[Gus Potter]

Slates are a natural material, do it properly and spend some time researching how it is important to cut them so they feather at the edges. How and where you tail a slate at a valley / verge say.

 

Why not buy say twenty slates and a slating axe, I have a left handed one so you can get these too. Once you have done your research and had a play with a few samples then you are well on your way to a good job.

 

Don't use a grinder or other gizmos.. you are inviting trouble.. your roof will not last as long.

 

I have copied below some of a previous post which may help give an over view.

 

Don't bother with a slate cutter. To get you started, buy a slating axe. I have a left handed one.. I use an off cut of a steel I beam over which I dress the slates.

 

You need to grade the slates. The thicker and wider ones go at the bottom near the eaves. I grade second hand slates ( you need to do this with new slate too to make a proper job) into three piles. You can do four but you may lose the will to live. Grading the slates basically helps you keep the roof tight and flat. Have a look at an old slated roof and you will see thicker wider slates at the bottom, thinner narrower ones at the top.

 

When you get to the verge or a valley you need to turn the slate and trim it the other way. What you are doing here is to encourage the water to move back into the roof in the case of a verge.. so it does not drip down the gable walls. In the case of a valley you are trying to stop constant dripping on to the lead valley and making a hole over the years. You try and channel the water down to the gutter so it drips here and this is where you often have a thicker lead piece. You call this "tailing" of the slate. This can't really be done with a machine..it's a craft.

 

In Scotland it rains a lot, much is light rain.. so it drips a lot. In England say you tend to have much more intense rain.. thus the flash flooding but more dry spells and less of that constant dripping.

 

The new home warranty providers and a lot of the slate providers require that all slates are double nailed at the head. Great if your poviding a 10 year warranty, eg if a slate cracks you often don't see it as it does not fall out like a single nailed slate. But a good well maintained roof should last for at least 80 years? For the roof pro's.. repairing a double nailed / every slate roof is hard going? You can fix the slate but the slate ripper causes more damage that is hidden? Yes there are repair type clips and so on but..

 

A common traditional method of slating in Scotland is to single nail each slate in the main part of the roof. Every third course you cheek nail a row of the slates, these slates now have three nails and stop the ones below from lifting off in the wind.

 

This way when you want to maintain the roof you can get into turn the slates and easily extract the broken one without damaging the felt / membrane underneath.

 

It's worth I think trying to master this skill, it can be very rewarding.

 

I have left this out but make sure you choose the slate nails carefully depending on whether you are near the sea or not.

 

You'll have a bit of wastage until you get the hang of it. Use the trimmings / wastage as decorative material for paths etc?

 

What is worth while doing is investing in a slate holing machine. You turn the slate upside down. The punch makes a concave hole in the top side of the slate and the nail head sits nicely inside so it does not tip up the slate on top..helps get the " tight roof". You can hole the slates by hand but I would suggest getting a feel for cutting / shaping / tailing them first.

 

 

 

Edited April 19, 2021 by Gus Potter

[joe90]

I have some slate cutters, older version of what’s posted above and they work well. I have cut slates in the past with a large trowel on edge using a chopping motion, works well but takes time. Angle grinders will leave an un natural “cut” edge and not look good (IMO).

mine is like this https://www.ebay.co.uk/itm/Tubela-Tile-slate-Cutters/294080302729?hash=item44788d4e89:g:6IQAAOSwSqRgWctV

 

but found this https://www.ebay.co.uk/itm/32cm-Slate-Cutter-for-roof-tiles-Slate-Spring-loaded-handle-rubber-grips/114764930971?hash=item1ab885df9b:g:6KMAAOSwgZJf-zuR

[epsilonGreedy]

10 minutes ago, Gus Potter said:

Why not buy say twenty slates and a slating axe, I have a left handed one so you can get these too. Once you have done your research and had a play with a few samples then you are well on your way to a good job.

 

 

Thanks I am going to re read your post a few times before I properly understand. I have 3000 slates onsite and have graded 600, so have plenty of rejects to practice on.

 

Your comment on traditional cut slates leading to a longer lasting roof is interesting. I have been wondering if the scissor like cutters or the guillotine put a twisting force on a slate leading to micro stress cracks?  Is this a concern?

 

I have concluded cutting all these slates is going to be messy.

[Cpd]

I have cut thousands of slates with a slaters axe and it is not hard to master, I have taught half a dozen people how to do it and it takes no more than an hour or two before they have got into the swing of it. It’s really the best way and gives a fantastic finish. 

[epsilonGreedy]

@joe90"sad face"?

 

Size of the job?

[Gus Potter]

Hi Eplison.

 

 

Thank you for taking an interest, much appreciated by me.

 

@Cpd good bit of encouragement here in that you can master the basic concept of hand cutting with an axe.

 

If you buy a good quality slate then it makes life easier as a beginner. Slates are not like glass thus the " micro stress cracks"  you mention don't propegate over time. Remember that we have been hand "axe" cutting slates this way for hundreds of years with no problem.

 

Once you understand the principles of slating then you are off to a good start. Yes it may take a bit longer if DIY but you can end up with a cracking roof. Using an axe is in my view a bit softer on the slates than these other mechanical devices. You'll soon get the feel of the axe and know when to go gentle, some of the slates will feel bit harder than others as they will have come out of a different bits of the quarry bed.

 

The main thing is to understand how you dress the slates at valleys, verges and chimneys as you use the dressing on the slate to channel water away from the vulnerable flashings and so on. Cutting with a grinder, shears are no match for this as they give you a square unnatural cut.

 

Also, if this is your forever home or if you want to do a sound responsible job then think about how you maintain the roof say in 15 /20 years time. Some of the modern nailing patterns seem very much driven by the "warranty", in other words once ten years has passed everyone is pretty much off the hook warranty wise but you.. a good roof should last for 80- 100 years if properly and easily maintained.

 

Pratically if a slate splits down the middle then if double nailed at the head it tends to stay in place while letting water in. You don't see it from the ground, great news if you are a new house builder. Not so good for you.

 

You often see slates double nailed at the head, some with hooks too. I can tell you that in Scotland we have been doing slate roofs subject to regular 100mph winds for a long time. A single nail at the head, every third row cheek nailed. This method allows you to maintain the roof without damaging the sarking / felt / membrane below as you can get in to turn the slates to access any broken ones. For the curious you may ask how may you compensate for different wind areas. Well if you use a smaller or heavier slate then there is less wind uplift per slate..

 

I hope this helps Epsilon. It can be very rewarding to do and I think you'll find that using an axe is the way to go.

 

From a professional point of view if I went to site and found someone saw cutting slates for valleys / verges etc then I would stop the job.

 

On balance I would have a go Epsilon as knowing that you have done the roof yourself and made a sound job is a great feeling. Also, if you get the odd slate that cracks you know how to fix it in ten minutes.

 

 

 

 

 

 

 

Edited April 19, 2021 by Gus Potter
Left handed typos