[gary6557]

I have bought a very old rough finished redwood slab to use as a counter top on my wives new island. The slab measures 90"x52"x3" and is rough planed on both sides. It is very dry with some rot on the side that will overhang the cabinets and whilst sanding it last night I noticed that one of the cracks would open slightly when I applied pressure to it. The crack is about 12" in from the edge, it does not run all of the way across. Any idea's on how I can make this crack structurally sound. Once sanded, I am going to oil to bring out the grain and then thought about an ultra clear resin, would the resin provide the strength or do I need to do something like straps underneath? Any help would be greatly appreciated.

 

[Bill White 2]

Put in "butterflies". They are the bow tie shaped inserts used to stabilize wood cracks.
Bill

 

[Dave Paine]

+1 with Bill, a bowtie will stabilize the crack and add a "George Nakashima" style repair.

A thread so you can see what we mean by bowtie, also called butterfly or Dutchman.

http://www.woodworkingtalk.com/f2/first-crack-butterflys-44045/

I am not aware of a finish which would be able to prevent the crack from getting worse.

FYI, the bow-ties only go 1/3 - 1/2 the depth of the wood.

If you are only making one or two, perhaps cut with hand chisel. Make the bowtie first, draw the outline on the slab and remove the wood in the slab with hand chisel.

Woodcraft has a template and bushing kit if you want to make more of these. I use them to add accents to cutting boards.

The template.
http://www.woodcraft.com/Product/2005514/16479/Butterfly-Inlay-Template.aspx

The router bushing kit.
http://www.woodcraft.com/product/20...-solid-brass-router-inlay-router-bit-set.aspx

Take the small bearing off to rout the bowtie. Put the bearing on to rout the bowtie shape in the slab using the template.

 

[GoNavy429]

How much gap can you get with the crack, might be able to use a glue syringe. Here is one with replacement needles, uses standard wood glue.

http://www.stewmac.com/shop/Glues,_...tors,_syringes/Glue_Syringe.html?tab=Pictures

or the cheap version

GLUE SYRINGE - 4 PACK by Peachtree Woodworking - PW6116 - Amazon.com


edit: Just an addon, I have done before a few years ago, but the crack I fixed went from midway through to the edge, but what I did and you have be careful not the break it off. I clamped one side onto a table with 1/4 small piece of scrap under the board between the crack and clamp. This leave the far side of the cracked piece about a half inch or so off the bench, then just lean onto it to open the crack some, BE CAREFUL...lol... shoot in some glue with the syringe, when you let up wipe off squeeze out, I didn't bother to clamp. I had to lean pretty hard on my piece, so i figure it had more then enough pressure. Worked out quite well.

 

[gary6557]

Thanks

Thanks one and all.