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The kitchen knife-block that I own appears to have been constructed by:

  1. Squaring off a large block of wood
  2. Cutting into two opposite sides of the block a number of parallel slots (blind cuts) that run from the top of the block to the bottom. The slots appear to have been cut with a table saw with a 4 mm kerf, and each slot is cut to a depth that suits the blade height of a particular knife
  3. Covering the whole of each of the two slotted faces of the wooden block with a thin sheet of decorative wood which stops the exposed length of the grooves, and thus holds the knives in place.

I'd like to make another, similar block. I'm looking for tips to help prevent the carefully-cut, narrow grooves from becoming clogged with glue when one glues the face-plate on at step 3.

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    Can you make strips of hardwood same thickness as knife slots?
    – Volfram K
    Apr 4 at 5:44
  • I've edited to remove the "best" as there's rarely if ever a best method to do just about anything in reality. And also asking in this way can tend to yield a favourite method, i.e. inherently subjective.
    – Graphus
    Apr 4 at 12:38

3 Answers 3

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Volfram K's suggestion will probably get the best results (and cause the most work): Cut a couple of wood strips 3.95mm thick. Or just slightly thinner than the knife grooves so they still fit when you cover them in something like packing tape so the glue doesn't stick to them.

You could try to stuff something else in there which doesn't adhere to the glue but I can't think of anything right now which doesn't stick, is easy to make in the right thickness and won't rip apart when pulling it out...

Personally I wouldn't actually worry about it too much. Just don't use more glue than you need and the squeezeout should be minimal. Afterwards, clean up the first couple of cm with a chisel (if you have one that is small enough to get in there) or a knife. You wont be able to see more than the first few cm and knives usually taper, so fit also shouldn't be a problem.

You could also glue, clamp, and then immediately remove the excess or spread it inside so it doesn't matter. Or cut a chamfer on the edges of the groves (not all the way to the top, so it wont be visible) which can take some of the glue.
Or make some sort of tongue and grove joint and only glue these so you don't get squeezeout in the knife grooves (requires higher precision because you don't have any glue filling small gaps).

Just don't use an excessive amount of glue and you should be fine.

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    Just don't use an excessive amount of glue and you should be fine. +1
    – FreeMan
    Apr 4 at 15:41
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When making knife blocks and similar sorts of glue-up situations there are multiple tricks that can minimise or prevent glue ending up in the milled grooves, and I think it's normal to use a combination rather than attempt to rely exclusively on one because just one can't be guaranteed to be effective.

Minimal glue
First and foremost I think is simply: don't apply too much glue, i.e. not the normal amount one would use when laminating for example.

Normally in woodworking you most definitely want to apply at least a slight excess of glue1, but here you can try to apply just enough, sacrificing absolute strength for ease of assembly/minimal cleanup.

Glue as normal, then wipe the glue from around the grooves
I've used this basic trick many times, but unfortunately with varying levels of success. So although it sometimes works great IME it isn't a sure-fire way to prevent glue ending up where you don't want it; combine it with another tip or expect to have to clean up some visible glue in the grooves.

The normal tool used by woodworkers to wipe excess glue away seems to be a fingertip :-) but a wooden scraper or silicone-rubber spatula could work as well or better.

Wax or finish the grooves, then assemble twice
This will only work if the decorative sheet is thick enough to allow it to be separated without being damaged; obviously this trick can't be used if you plan to use anything like a veneer thickness.

Here you basically glue as normal, press the parts together, separate them to clean out the glue from the grooves (hence why you wax or apply finish to them beforehand), then bring the parts together one final time and apply full clamping pressure.

You may (in fact are likely to) get some minimal squeezeout along the edges of the grooves when full clamping pressure is applied — little drops dotted along the edge — but any you can't reach from the top to clean up will be A) invisible in use and B) very unlikely to be large enough to cause an issue given the very generous sizing of the slots.

Fill the grooves with something first
If you fill the grooves with close-fitting strips of plastic, or a fine-grained hardwood (maple would be ideal) well waxed to prevent glue sticking to them.

This might work well enough by itself that it could be used solo, assuming making the strips of plastic or wood isn't an insurmountable obstacle2.

Give somewhere else for the glue to go
This trick is not new, but seems to be gaining increasing traction in recent years as a method to minimise or eliminate squeezeout when certain joints are assembled.

If you want to employ this here I think the way to do it is to create very shallow stopped grooves alongside the knife grooves. The first method to do this that I thought of was to use a router (either hand or powered), but actually just cutting V-grooves using a sharp knife and a straightedge might be all that's needed, and this would be far faster and require no setup.

Use contact adhesive
I wanted to include this for completeness, although I wouldn't favour this method myself as although the initial bond will be plenty strong I'm not confident it would hold up over the years, plus the glue line might be thicker than you'd really like it to be, so visually intrusive.

But in its favour, because contact adhesive is applied to both faces and then allowed to dry, you essentially can't get squeezout. Of course you're likely to get some adhesive in the grooves during application, but that's relatively easy to prevent, or remove while the joint is still open.


Note applicable with any glue used
I think it's possible this might not be immediately obvious so do bear in mind you wouldn't want to apply glue to the entire of the decorative sheet, because you'd end up with glue on one side of every knife slot. This would be particularly unwanted in the case of contact adhesive since this remains tacky.

To prevent this you'll need to carefully mark the positions of the slots on the inside face of the sheet and either mask them off before spreading the glue, or brush around them.


1 Excess glue being mostly — or ideally all — squeezed out as the clamps are fully tightened. This is what gives the best chance of the strongest joint being formed with the two most common woodworking adhesives, yielding no dry spots (AKA 'starved' areas) which are weak points.

2 Impossible or too tedious to be bothered with :-)

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  • Contact cement was my first thought.
    – FreeMan
    Apr 4 at 15:44
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I'm looking for tips to help prevent the carefully-cut, narrow grooves from becoming clogged with glue when one glues the face-plate on at step 3.

Consider using cyanoacrylate (CA) glue. CA glues are available in a range of viscosities, and the thin versions tend to soak into wood rather than squeeze out, which is useful for your purposes. CA glues aren't normally used for lamination because they don't allow for a long open time, but it doesn't sound like that should be a problem in this case.

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  • I know this isn't a critical use-case but given the known brittleness of superglue I wonder about how reliable this would be on a fairly wide joint face like this over the longer term.
    – Graphus
    Apr 5 at 19:10
  • @Graphus There are a lot of unspecified variables here, including the thickness of the "thin sheet of decorative wood," species, location, and whether the slots run all the way to the far end of the block. In general, though, I don't think there'd be a problem as long as the decorative piece has the grain oriented the same way as the rest of the block. If the main block is maple and the glued-on piece is walnut, for example, the difference in seasonal movement between them is going to be pretty small.
    – Caleb
    Apr 5 at 20:10

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