Thread: What to do with crack in Blackwood slab?

Groggy has a great fix for this and the join will not be as visible as if you use your suggestion.

Wait and he will see this thread and answer for you.

Cheers

Dominos?

If you want to leave it as one piece, you may want to consider using a butterfly joint on it.

I think I need a better memory. Calm called me to remind me of a method I have mentioned previously (thanks mate, grey cells ain't what they used to be).

• First up, cut the piece up the crack using a saw.
• Clamp both pieces to a bench and set them a distance apart that is 2mm less than the width of your router bit.
• Then put a straight edge along the top of one of the boards to guide the router bit, making sure it takes the same amount off each piece.
• Work slowly, making multiple passes as it is a thick piece.
• Finally, do one full pass that removes a fraction from each piece. You should then have an almost invisible seam.

Because you cut them both at the same time any imperfection in one should be mirrored in the other, making a perfect fit.

Thanks guys, your advice is much appreciated!

Groggy, I take it that I don't need to adjust the guide for the passes made by the router? Or do I need to make slight adjustments each time?

Also, I would need to plane these slabs before using the router, as I don't think I've got a straight edge long enough. How long do straight edges get?

Cheers,

PG

I have a straight edge that is 2m long. A piece of aluminium rectangle section works well for the task.

For the final pass on the router your will need to move one piece in marginally. Planing the slabs will help a lot.

Where about in Melbourne are you? If you're in the eastern Suburbs, I can loan you a straight edge.

Ah - I used the wrong terminology. My apologies. I meant 'straight' bit for the router - my longest two flute straight bit is 32mm. I'm guessing that after planing, this slab will be around 50mm (currently 60-70mm) in thickness. What I meant to ask was how long to straight router bits get?

Come to think of it, I would need a longer straight edge as well - my spirit level is dead straight but only 1 metre long. DJ, thanks for the offer, I'm in Heidelberg - not quite eastern suburbs. Wouldn't Bunnings or Mitre 10 have straight edges?

PG

You could always use a nice straight piece of lumber I often do as a long straight edge. as for routers you may not find one long enough at bunnings but good tooling suppliers and saw shops should have bits considerably longer or have the capability to make them longer than what you can buy.

I cut through the crack on the band saw (start on the crack end and saw through to the other end) - then glue the two pieces back together. After the glue drys and if the crack is still visible I cut through it again following the glue line from the first cut and glue the two pieces back together again. Repeat until the crack disappears usually only takes 2 or 3 times. It doesn't matter if you cut a straight line because both piece will match, it's usually best not to cut a perfectly straight line as this helps hide the glue line and remember to follow the glue line each time you saw through

Thanks

Hi Jeff,
I think your process of repairing the crack is a really good method.
I have some some small slabs that your method is perfect for me to practise on.
Many thanks for sharing.
Glenn

https://www.woodworkforums.com/member...dding-present/
Here's what I did when I came accross a little crack. In flicking through as I'm writing this, though, I'm not the first to mention Butterfly keys. With something like yours I could only suggest you make yours a decent size and in a dramatically contrasting colour to make it look like a feature and not like you asked everyone what to do

Jeff Mills got a really good idea a couple of posts back though Maybe just do that

Lovely solution and craftwork, Eldanos.

A refinement to your solution would be to drill an "extension limiting" hole at the end of the existant crack to prevent that split from extending further. The hole must be large enough that no part of the split bypasses it - the crack will not be absolutely vertical.

I have also seen a far less spectacular table where the maker rebated around the large central holes and inserted glass panels, so as to give a perfectly flat table surface. (Tas Design Centre, I think).

Cheers

Graeme