Black walnut slab questions!

[kenny zaleski]

I have a black walnut slab that I am finishing for a console table. After planing, the piece is starting to crack in several places. I attached some pics.
What is my best way to proceed? Do I attempt to epoxy/glue and clamp these spots?? Are these spots too bad to salvage and must be cut off?
This is only my second live edge project, but I know wood finishing well. Any help is much appreciated.
Thanks!
Kenny Z


IMG_7458.jpgIMG_7457.jpg

[Jamie Buxton]

Those look like cracks that were there before you stated milling anything. I'd flood them with epoxy, clamp them as best I can, and accept that there will some places where the wood does not fully close together, so you will see some epoxy in the finished product. I use epoxy from West Systems, or System Three sells the same stuff. It mixes up to the consistency of pancake syrup, and will flow into the cracks. You might leave it clear, or you can color it. Transtint dyes color epoxy well. Some folks like black, but I like brown.

[kenny zaleski]

Thanks Jamie, that's what I was thinking as well. Since you're very familiar with epoxy, what options do I have when it comes to epoxy curing in cold temperatures? Most epoxies seem to recommend between 70-85 degrees, however I am in Ohio and currently that temperature range is not attainable for me. Do i wait for warmer days, or have you found a remedy/fast hardener that works well in the cold? I don't want to jeopardize my final result.
Thanks!

[Chris Padilla]

Can you either warm up your shop or take the wood to a warmer place to work the epoxy in?

There are many ways to handle the cracks. Some like to hide them...some fill them to blend in. Some fill them and highlight them. Some highlight the crack itself with a dutchman (double dovetail). Each to his own how to handle it but live edges and the swirling grain of walnut can very easily lead to such events happening. Your cracks look more like surface checks that do not go through the wood. They can be tougher to deal with. Flood with glue, clamp, sand, see how it turns out. Maybe the worst offender become the bottom surface?

Do you plan to dye the sapwood to match better?

I love walnut...it is one of my favorite woods to work with.

[kenny zaleski]

Hey Chris,
Thanks for the info. Unfortunately I cannot move the project to a warmer place. I do have a propane heater that throws out a ton of heat, but for me to keep that temperature range for the duration of curing, it will take a miracle. My shop is my garage, and it is not insulated whatsoever. Whatever heat I generate goes away quickly.
I will make the worst crack the bottom....however I have this issue on both sides of the piece. My first picture shows the lesser of 2 evils, which I will work with as the top.
I never considered dying the sapwood to match, however I will definitely look into this as an option!
Thank you!

[Chris Padilla]

Behlen's NGR Dye is one I use A LOT. The color "Hickory" (I know...no clue why they named it that way) is, IMO, perfect to dye walnut an overall chocolately color. I used it to help dye reddish walnut more brown/chocolate and the same with walnut sapwood. Lately, I've used it to dye maple a dark walnut brown. One caveat with dyes is that they can be challenging to physically apply like with a sponge or brush or rag...especially on maple. I spray my dyes and they come out excellent. I did sponge the dye on the walnut and it did work well but it isn't as tight and variously pored like maple (and cherry), which can be notoriously difficult to stain evenly (blotching).

As to your temperature issue, you'll just have to leave the epoxy alone for a few days while it cures. It will cure, I believe, but it'll just take much much longer. Instead of a day at 65 or 70+, it could take 3-4-5 days to cure in the 50s/60s. Some guys will wrap the wood in an electric blanket to help with curing during the winter months.

You should seriously consider insulating your garage. I did mine several years ago...has made a world of difference in there.

[Nelson Howe]

I have luck making a tent of moving blankets kept warm with a lightbulb when using urea formaldehyde glue.

Nelson

[Ed Aumiller]

Is the wood dry enough to work it ??? If it is not dry to 8-10% then as it dries out, it will probably crack even more...
When you planed it, it possibly allowed the inside to dry causing the cracks...
Check moisture content before proceeding would be my suggestion..
Good luck..

[Jamie Buxton]

Thanks Jamie, that's what I was thinking as well. Since you're very familiar with epoxy, what options do I have when it comes to epoxy curing in cold temperatures? Most epoxies seem to recommend between 70-85 degrees, however I am in Ohio and currently that temperature range is not attainable for me. Do i wait for warmer days, or have you found a remedy/fast hardener that works well in the cold? I don't want to jeopardize my final result.
Thanks!

West Systems says their 105 epoxy with the 205 hardener will cure down in the forties. They don't recommend using it below 40 degrees F. At 40, it might take days to cure. Curing time is strongly dependent on temperature. I get it cure overnight in a shop that probably gets down to low fifties in the winter.

[kenny zaleski]

Nelson - that's a great idea...I may have to try that!
Jamie-thanks for the info. I think I'll have to roll the dice a little bit. My forecast this week is very cold...I'll continue prepping and let the weather break, then give it a shot.
Chris- I've been kicking the idea around about insulating. My only problem is my attic above the garage is my #1 storage area for the house. I guess I'll have to pick my poison.