How to a corner join on curved benchtop with no masons mitre?

Hi @JR2,

I understand the challenge you're facing with the curved edge and the corner join. While a mason's mitre is typically ideal for creating seamless joins, I'm unsure why the 28mm thickness of your benchtop should not actually prevent you from using this technique. If you have enough material to work with, a mason's mitre should still be a viable option. If you’re unable to execute this cut yourself, you could opt for a standard mitre joint, which would work better than using joint compound, silicone, or paint to fill the gap. These options can lead to an uneven or visible finish over time, so it’s best to avoid them if possible.

Another alternative would be to enlist the help of a professional benchtop installer, especially if you want the join to look flawless. A professional can make the precise cuts needed to align the curve and the straight edges seamlessly, ensuring a neat and durable finish.

In short, if you have enough material, a mason's mitre is the way to go. If not, you might need to rethink the joint method or get expert help.

Let me tag @Dave-1 and @Nailbag to see if they have any thoughts.

Please let me know if you have any questions.

Mitchell

Nailbag

Hi @JR2

I agree with @MitchellMc that a conventional mitre joint in lieu of fillers would have a more seamless join. It would also be worth considering his suggestion of getting a professional to make the cut and join. It's a cut that requires a high-level of skill and the correct tools and setup to perform manually.

As another alternative, there is a product called "Mason's Mitre Trim" which fills and covers the gaps/imperfections. This is available from online retailers.

Nailbag

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Afternoon @JR2

Mmmm I m trying to picture your "slight bend" But am unsure of if its on the level part of the bench or the edge? Any chance of a couple of photos to show the issue? I would normally be agreeing with @MitchellMc about how to approach this but think I am missing something info wise.

Also Just learnt something new! @Nailbag's mention of "Masons miter trim" 😲 Will be filing that away for future use 🙂

Dave

thanks! I’ve attached some photos below. The edge facing towards the front is curved and the back is a square. So joining the two will leave a gap.

the carpenter I asked said it was not possible to use a masons mitre as it requires 35mm to work with. What is a conventional mitre? Is that just a butt join? If so, that is what I was intending to do however just wasn’t sure how to cover up the gap that the curved and square edge would leave

Afternoon @JR2

Ok, makes more sense now. You are reusing a curved edged bench and like me have used a term to the carpenter that might mean something else (I do it all the time 🙂 ). I would call what you want a butt join or square join, but thats just the name in my head. These bench type connectors are what you may be thinking of using? Kaboodle Benchtops Join Kit in Products

I dont see a problem with cutting a flush edge so you can join another piece at 90 degrees. I would have another chat with your carpenter and see what they say. I know I could attempt it but also know there is a fair chance I may not be as accurate as I need to be.

Do you know if the benchtops are laminate? If they are ceasor stone or a manufactured product that would add complexity to the job at hand.

I do really like @Nailbag's backup solution in case its not possible.

Dave

A mitre joint is where both benchtops are cut at a 45-degree angle and joined together @JR2.

Mitchell

Hi Dave,

they are laminate benchtops. The front end is straight at the bottom but towards the top there is a slight curve where the 90 degrees is that joins both the horizontal and vertical of the benchtop (not sure if that makes much sense!). That’s where I would foresee a gap since I will be connecting a flush square edge to an edge with a flight rounding at the top

Got it thanks, would I need a significant amount of excess for this cut since the bottom is a different colour? So I can’t just flip it over to connect the 45 degrees

Evening @JR2

A Butt join would use less of the bench itself. Are you thinking of the miter cut (45deg angle) or a butt join (flush surfaces)?

Dave

Oh, they are laminate benchtops @JR2! Now I understand better.

For a mitre join, both your benchtops would need to span the full length of their walls. In the corner, they can both be cut at a 45-degree angle.

I've created a 3d render of a 28mm thick bench with a corner on the top edge. I can't see why a Mason's mitre couldn't be used in this situation.

Mitchell

Afternoon @MitchellMc and @JR2

The second pair is what I had pictured in my mind. I wasnt too sure if the reused benchtops were exactly the same so figured the square join would be easy to line up.

Dave

https://www.bunnings.com.au/practa-2400-x-600-x-25mm-white-laminate-worktop_p2660665?store=6425&gad_source=1&gbraid=0AAAAADtbEB-poqAyGOK5-2Q7ia1nv_Op-&gclid=CjwKCAiAm-67BhBlEiwAEVftNvXgodMNzKkFwooo9kA49hypdMhNyVD_mMi-QLFc9LrAgsrMh7zRohoCYSgQAvD_BwE&gclsrc=aw.ds

Thanks all. I am considering just getting a new benchtop as two installers have now said they’re unable to butt join!

I am looking at the practa solutions benchtop. Some of the ones I’ve seen in store still have a post formed radius edge whereas I need a square edge. I can’t find any info online about the edge type of the one linked below, can you help?

Hi @JR2,

That benchtop has a chamfered corner on it, so it's not a perfect right angle. You could butt joint them, but there will be a similar issue to your original benchtop, just not to the same extent. A mitre joint is what is required here to avoid this.

Butt joins are not commonly used for any benchtop that does not have perfectly square edges.

Mitchell

Thanks Mitchell. I had already purchased these as when I went into store and was told they should be square edges. I wonder if I can just flip the benchtop over, so the chamfered edge will be at the bottom so it is easier to butt join?

Alternatively. Will it be ok to just caulk the gap between them after butt joining or will the gap be too large to cover with it?

Otherwise please let me know what square edge benchtop there are at 600mm depth at a lower price point.

Well, they are square edge, in the sense that they are not rounded @JR2. I think you'll find all the edges are chamfered. You could attempt to use caulking to fill the very small gap.

Most benchtops will not have a perfectly square edge as, typically, benchtops are not joined with butt joins.

Mitchell

Thanks Mitchell. Would you happen to have a close up of a render of what the edge looks like? Especially if butt joined?

It's a bit hard to show as the corner is so small @JR2. It will look something similar to the below. There will still be a tiny joint line, but nowhere near as bad as using the curved edge board.

Mitchell

Something like the below? Is the image below the same edge as the practa solutions benches I linked?

Hi @JR2,

Yes, that's a very similar edge.

Mitchell

Nailbag

As the finished join will have a dirt trapping groove, would you recommend some form of clear epoxy to fill it level to the benchtop @MitchellMc ?

Nailbag