Thread: Clamping a mitre for waterfall bench top whilst in-situ. How?

I'd just be using masking tape, that's how we do folded items at work. I would also NOT use dominoes, or anything else in the joint, there will be no load on the joint and dominoes will only make it harder to get the joint nice and tight

Have you checked to see whether there is already a fitting available to do this ?

I know lots of companies make fittings for joining flat bench tops together - usually some type of screw coupling. I'd be surprised if there isn't also one for waterfall benchtops as they are quite common and I doubt the commercial kitchen installers mess around with clamps and glue.

cheers
Arron

You're probably right. I'll check with my joiner when I take the laminated sections to them.

Originally Posted by Arron

Have you checked to see whether there is already a fitting available to do this ?

I know lots of companies make fittings for joining flat bench tops together - usually some type of screw coupling. I'd be surprised if there isn't also one for waterfall benchtops as they are quite common and I doubt the commercial kitchen installers mess around with clamps and glue.

cheers
Arron

Hi Arron

not disagreeing, but

from what I can see via Dr Google, waterfall ends are typically manufactured stone or laminex on chipboard
Manufactured stone is glued and clamped and also wedged off the floor to get a tight joint.
I'm not sure how chipboard ones are joined, but a butt joint with the laminex applied after would seem the easiest

Mat wants to use solid timber, and IMO should use a timber joint.
A straight mitre will be relatively weak, unless the waterfall panel is screwed to the carcass, which will present all sorts of issues around allowing for timber movement.
Dovetails would look really spiffy, but could be difficult to execute by machine.
perhaps a lock mitre joint will be the easiest to execute.

BTW, Mat
if you screw your bench top to both the front and back of the carcass you're just asking for trouble

Hi Ian and yes, I agree - we will need to allow the timber to move somewhat independently. I can guarantee this stuff is mighty heavy and hard, so it's not exactly gonna blow off. I've head some people just put maybe 2 screws though from inside the carcass to secure the waterfall whilst curing the join, but that's it. image.jpg
This pic is only 1/2 the bench width, and it's over 3500 long.....
Here's my Medieval looking clamping setup:
image.jpg
And this is what I'm aiming for:

Blog — Bombora Custom Furniture

Mat

Did one like this a couple of years ago (about 1400 wide?) with the timber doubled up to about 80 mm for the vertical and around the edges of the top. Dominos were used and the whole thing glued up in the shed. clamps were used along the length and height to pull things tight. Took 4 people to carry the completed unit.

Hi Mat,
Here's what I would do.
I'd cut some blocks about 300mm long out of something around 50x50, and cut a 50° splay on one end. Screw these to the face of your top and waterfall piece so that the short end of the splay is about 5mm back from the long point of your mitre. Make sure that the blocks on the top and waterfall are in line. The long point of the splay will now extend beyond the mitre and you will be able to clamp it to the back end of the block on the opposing piece of benchtop/waterfall. I'd probably use 4 sets of blocks across the width. You will end up with screw holes in the faces which will require filling, but seeing as your panels are highly figured, that shouldn't be a problem.
If this doesn't make sense, let me know and I'll draw you a diagram.
Cheers,
Chris

Find someone in your area with a Lamello Zeta Biscuit joiner, check the video link for your info.

Zeta P2 - The profile biscuit joiner for P-System connecting fittings - Lamello AG

Originally Posted by wood spirit

Did one like this a couple of years ago (about 1400 wide?) with the timber doubled up to about 80 mm for the vertical and around the edges of the top. Dominos were used and the whole thing glued up in the shed. clamps were used along the length and height to pull things tight. Took 4 people to carry the completed unit.

HI mate. What clamps were used? I can see how clamps could be used at each end, but how do you clamp along entire join? I can use 2 of something like Bessy WS3 angle clamps, but then what?

Originally Posted by cjbfisher

Hi Mat,
Here's what I would do.
I'd cut some blocks about 300mm long out of something around 50x50, and cut a 50° splay on one end. Screw these to the face of your top and waterfall piece so that the short end of the splay is about 5mm back from the long point of your mitre. Make sure that the blocks on the top and waterfall are in line. The long point of the splay will now extend beyond the mitre and you will be able to clamp it to the back end of the block on the opposing piece of benchtop/waterfall. I'd probably use 4 sets of blocks across the width. You will end up with screw holes in the faces which will require filling, but seeing as your panels are highly figured, that shouldn't be a problem.
If this doesn't make sense, let me know and I'll draw you a diagram.
Cheers,
Chris

HI Chris. I don't quite follow? I'd like to avoid screw holes as plan to apply most of the finish prior to clamp (will be difficult to work once joined as so big and heavy).

Originally Posted by fishflog

Find someone in your area with a Lamello Zeta Biscuit joiner, check the video link for your info.

Zeta P2 - The profile biscuit joiner for P-System connecting fittings - Lamello AG

I have a Festool Domino that can place dominos at 45deg into mitre, which I plan to use. If we get it right this will guide join. I need, however, a clamping method whilst the epoxy cures.

Originally Posted by wood spirit

Did one like this a couple of years ago (about 1400 wide?) with the timber doubled up to about 80 mm for the vertical and around the edges of the top. Dominos were used and the whole thing glued up in the shed. clamps were used along the length and height to pull things tight. Took 4 people to carry the completed unit.

Did you use the Dominos on the "tight" settings and just (carefully) hammer into place? If we can get them right this might almost be enough whilst glue cures?

Here's where we're at, with a (trick of the angle) shot to show what we need to achieve!

IMG_1443.jpgIMG_1435.jpgIMG_1436.jpgIMG_1437.jpgIMG_1438.jpgIMG_1439.jpgIMG_1440.jpgIMG_1441.jpgIMG_1442.jpg
I can clamp either in-situ or on floor then lift into place. The end is deliberately left long until we know our join will work, so we will maybe cut dominos, do a trial run, undo (?might be hard if tight dominos), glue, then (how to? clamp). As you can see, it's hard to find a way to clamp in the centre (each side easy with an angle clamp).
Maybe we do in-situ and just weigh the top down? It won't slide due to dominos?

Just wrote a whole reply, went to search for something, then lost it. Bugger.

To clamp, I'd cut a big triangle from an offcut from the bench or something else strong. Cut a big circle in it, big enough to hold two clamp heads, then clamp in both directions. As long as you place it right, you should be able to apply strong pressure.
You could screw as well to hold the top or middle, but I doubt it would have enough strength to do much.

Definitely use dominoes, as much for alignment as anything. And do a dry run.

Arron was talking about using this kind of zip bolt. Have a look here. Not sure how you'd cut the right slots, but it is probably pretty easy.

Good luck and be sure to post the results.

Trav