I bought a chopping board not so long ago.
Macrocarpa, roughly 20 x 12 x 1.2"
I like a very big board as I often cook large quantities.
I got it really cheap as it had started to develop a deep split.
I'm assuming the wood is not cured, or great quality.
Anyway, the board fell sideways onto something, and snapped completely in half along the split.
I know nothing about this stuff, and I'm getting the impression that glues don't often come in 'food-safe' and 'very strong'
First off, is it worth the trouble?
I'm thinking: drill/glue dowels to join the halves, glueing along the split as I go, then clamp.
I see glued chopping boards all the time, but none as big as this.
I may cut it down a bit as I think it's sheer size and weight will make it weak, whatever I do.
Any suggestions?

Titebond brand glue is "food safe" Titebond 3 is waterproof once cured, too. There are others that are made for making cutting boards, too. I don't know what you have available in your area.

For splits like that, I have the best luck just gluing and clamping, the rough nature of the split makes enough key and grip that it goes together straight and has never broke in the same place. If you start trying to dowel a split, it often won't go back together right because you need to wiggle it back together. Make sure to clamp it with straight edges along the faces so it doesn't bow.

What tools do you have? The glue face needs to be clean, not aged in oil/water, whatever. You mentioned a split had started and the inside of that split will not be a good glue surface because it will have gotten dirty. To get good surfaces you usually run a piece through a _well set up_ table saw to make the edges perfectly straight and at perfect 90D angles to the face of the board. The _outside_ edges which you will clamp against also must be perfect 90D to the face or clamping will tend to bow the board one way or another. Use plastic wrap or wax paper to keep the glue off big stuff like the work table; use masking tape along the glue edges if you want to keep the squeeze out off the surface of the board.

That said, just go for it as best you can. <g> I mean if you have a saw, how much trouble is it to cut it, glue it and break it again? Then you try a different glue. The 3rd time you try something fancy like a cross-grain spline or some dowels. Even a good circular saw, carefully set at 90D w/a square and run against a straight edge (any damn straight piece of something...) clamped to the board will give you a plausible excuse for a glue surface.

Best luck.


Rufus

Thanks guys.

Rufus Laggren wrote:What tools do you have?(...) you usually run a piece through a _well set up_ table saw

No useful ones for this. I know someone with a drop saw, will that do? We're talking definitely not a well set up table saw...
Most of the crack face is clean, but it's a good chance cut the size down a bit in all directions.
I'll have to scare up some clamps.

> clamps

Pipe clamps. Yard sales etc. 1/2" type (pipe) will work, 3/4" is better. The cheap type with really short jaws, just 1-1/2" right off the pipe, works best here; the long throw jaws type for "reaching in" will just be a pain, more $$, also. You can get the pipes with the clamps (yard sale) and/or find the right length/size pipe later.

With the short throw clamps, lay the clamps on the (FLAT) table, jaws facing up, lay the board on the pipes between the jaws.

> drop saw...

Got me there. Do you mean a chop saw? Captive circular saw hung over a table on an arm, pull it down to cut...

> will it do/...

The work piece (the board) has to be completely cut by one movement, either running the saw over it or pushing it through the saw. Otherwise you're faced with the need to make a perfect 2nd cut - good luck. Cutting flat stock (plywood, boards, etc) can be done really well with a half decent circular saw and a straight edge + a couple small clamps to hold the straight edge tight on the work piece. Really, REALLY helps if the blade is sharp (applies to all saws). A common straight edge is a left over piece of 1/4 to 3/4 plywood with the factory edge intact. But anything else straight will do if you can clamp it to the work piece. Beware - the saw has to clear the clamps at both ends.

Rufus

If you're still mulling this about, a hand plane and a machinist's square are all the tools you'd really need. The plane needs to be longish, something like a Record #05. Plane both edges down to clean wood, making sure that they are straight and square. For basic tutorials, search "edge joining" or "edge jointing" (both are common) and "winding sticks". In order to apply the clamping pressure:
1. Lay the two pieces on a work table.
2. Attach blocks to the table along the edges of the workpiece that are parallel to the crack.
3. Apply glue to one edge of the joint, spreading thoroughly.
4. Drive wedges or tapered shims between the blocks and workpiece to apply pressure to the joint.
5. Let it sit for a day before stressing the joint.

The tip about Tightbond is good; i'd use Tightbond II. You should fix this if only because hand skills are worth developing.

Thanks Mark
Yes, my board is still sitting in two pieces.
I glare at it and feel inadequate daily...
From what I understand, you need some woodworking chops to manage a plane?
I have none. Zero.
Stuff it.
I'm totally with you on developing skills. I want some!

Sure, some chops are good, but that's the thing about developing hand skills: it's cumulative. Doing creates the ability to do. You don't have to be Mario Batali to cook dinner, nor do you have to be Sam Maloof to make shavings.
What's the harm in trying? Hand planes are inexpensive, can be useful for generations, are not obnoxious to use, and are highly unlikely to take an inexperienced hand off. And otherwise, you've got a lot of board to work with. If you can whittle through both halves without making two joinable edges, then fine: take your pile of shavings and go make a plant happy.

the best way to fix it is with a biscut joiner and glue, but if you dont have a lot of tools, you could use wooden dowels. If you use dowels make sure the size of dowel is small enough to leave the same amount of wood above and below the centered hole. Also to make sure your holes line up you can make a quick jig by screwing two boards together into a T shape and drilling a hole through it first. Line up the two halves of your cutting board, make marks on both halves (offset to the actual hole in the T, the distance of the edge of the T to the center of the hole) line up the edhe of the T on one side and drill it straight, and do the same on the other side. Glue your dowels before you insert them and then clamp the whole shebang together. Dowel size should be determined by sliding them in and out with a little friction but no slop. Things NOT to do--- Cut your dowels too long, drill your holes crooked,

I would go with the modern glues for ease of use. Several are rated as waterproof and food safe.

There are waterproof old organics too. Hide glue and Casine glues can be waterproof enough for a cutting board if you don't leave it soaking in water long term. Shellac glues would be another possible but they are not as strong. Casine glues level of waterproof varies depending on the recipe it is made by. It is actually used to make children's washable glues but with other recipes can be nearly waterproof and it was used in early aircraft construction.

Thanks for your ideas everyone!
I fixed the board ages ago, but I forgot to say anything and found my photos
I was thinking it would be fiddly because of the board's size/weight,
but in the end I just put a good coating of wood glue on both surfaces, left it in F-clamps for a few days and scraped/sanded off the glue residue.
The board now lives flat on the bench, and has shown no sign of being anything less than awesome
I'm so glad I didn't cut the board down-I can chop up a whole cabbage for sauerkraut and it pretty much fits on the board.