hard maple end grain color issue

[Charlie Fox]

made several cutting boards in one batch - shown is a 25"x19". wood is hard maple, teak, and white oak. First sanding was a commercial 26" belt sander at 50 grit, followed by Festool Rotex at 100, 150, then 240. good long, sanding sessions. anyone know what i am doing wrong to have the maple dark in the middle and light on the edges? did a smaller board with grit belt sander followed by Rotes at 100, 150, and 240, same result. the scratches from the 50 were tough to get out, next time i will pay them extra to use more like 120, but even using edge of the Rotex in aggresive mode and 2 pairs of reading glasses to see the work at a near-molecular level the same thing happens, so it pretty much rules out the sanding. with a google image search of end grain maple boards i see many with the same appearance but no discussion of it, but i also see other boards with the maple a uniform color. its almost as if the glue is having an effect in the joint areas. it is uniform and occurs between joints with maple as well as the other woods. any ideas?

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[Jamie Buxton]

I don't think that's something you did. Notice that on most blocks, the two long edges are light, but only one short edge is light. My guess is that the light color happened during drying, and the one dark end is the one you ripped heavily to dimension the block.

[Charlie Fox]

interesting - thanks. its also present on Boos works as well (below)
its not a bad look, but sometime i am going to want a light color, guess i have to try different planks, fortunately i live in Houston and have 3 hardwood sources within 5 miles.

http://www.kitchensource.com/kau/jb-welcome.html

[Andy Giddings]

Oil from the teak going into the maple end grain maybe?

[Prashun Patel]

Perhaps it's glue from the joint that has sealed some of the end grain

[Cary Falk]

Maybe it is the walnut dust getting into the end grain in the maple. You would think it would be more uniform if it was. Maybe parts or the maple are more porous than others. I know it is a problem in general with light and dark color woods together but I don't think I have heard anybody making cutting boards talk of it. Those are common woods for cutting boards.

Edit: Didn't read the text close enough, just looked at the pictures and thought walnut instead of teak. Change my Walnut response to teak

[Andrew Hughes]

I agree with Prashun it's the glue.

[Phil Mueller]

It appears the darker shades in the maple is present on the long grain (ends) as well. There is also shading in the walnut.
If it's not the glue, then I'd say it is simply the stock.

[Chris Fournier]

I can't understand how it can be the glue. Maple is closed grained. Also that cutting board had to start considerably thicker than it is now I would think and glue isn't going to be a factor. I base this on the practice in my shop of gluing up end grain cutting boards about 1/4" over finished dimension. I also don't sand, I thickness plane my boards with fresh knives in the jointer planer.

End grain maple can often times have that colour variation and I would bet it has something to do with kiln drying.

[Andrew Hughes]

Just going by what I have noticed when making maple boards.Looks familiar to me water from the glue has to go somewhere and it creates a ghosting affect around the edges of each pieces.
Its all very scientific you probably wouldn't understand.:)
I think it looks great.

[Myk Rian]

Maybe it is the walnut dust getting into the end grain in the maple.
That's my guess.

[John TenEyck]

I think you have multiple things going on. Glue might have sealed up the maple near the glue joint, but it I also think some walnut or teak dust is coloring the interior portion of the maple which remained more porous. It's just hard to believe your maple was that dark on it's own and, if it was, why would the edges be light after gluing?

John

[Prashun Patel]

The glue would be coming from the sides not the ends. I suspect this happens with all woods but might only be noticeable on lighter woods? It happens on my maple boards.

I just squirted with mineral spirits a maple end grain cheese board I am making and I can certainly see color differences around the edges.

Might it be burnishing caused by excessive sanding of the seams? But then again the board I am working with has not yet been sanded . Only planed .

[Charlie Fox]

Just going by what I have noticed when making maple boards.Looks familiar to me water from the glue has to go somewhere and it creates a ghosting affect around the edges of each pieces.
Its all very scientific you probably wouldn't understand.:)
I think it looks great.


Just going by what I have noticed when making maple boards.Looks familiar to me water from the glue has to go somewhere and it creates a ghosting affect around the edges of each pieces.
Its all very scientific you probably wouldn't understand.:)
I think it looks great.

i think this is the best answer - a lot of other great answers - but - BUT there is no walnut in this piece so how could it be the walnut dust? and no way it could so evenly spread all over given the wood variation pattern.

so - if it is the water - then maybe letting the boards dry for a month or so may help?

but as a geophysicist/environmental geologist the "science" doesnt scare me... ;-) i may not "know" it, but can certainly understand it

what a great forum - thanks to all for your input and for future inputs.

so today i milled some old "tricksy" osage orange, we'll see how that turns out

[Andy Giddings]

Just a thought - when you were sanding with the Rotex did the sanding disc show any coloration?

[Ben Abate]

I ve read all the posts saying it's the glue or the non existing walnut. Is it possible that the oil from the teak is causing the problem? If you still have access to the wide belt, try to sand one of the boards again but first wipe it down with denatured alcohol. Let the alcohol dispense or it will give you the same problem. But do it in a timely fashion so the oils are still below the surface. Does this make any sense. Teak is oily and dense the oil and the saw dust seem to be combining to creat the smear. The heat of the belts or sander just keeps spreading it.

This is is what I think is going on hear

[Andrew Hughes]

Well I still say it's water from the glue.How often do we see the affects of glue on end grain?
Heres maple and cherry that was planed with a Bryd head and the maple has liteness around the edges and the cherry does too.It has mellow some but I can still notice it.
No sanding was done.

[Steve Demuth]

Charlie,

Whatever the effect is, it is mediated both by the wood, and the glue-up. You can easily see that there is a component of the effect that carries elements of the pattern across adjacent pieces of maple, which strongly indicates that some aspect of the wood grain structure that is consistent in the board over multiple inches of it's original length is at play. There is also, as you called out, a pronounced edge effect. So, my working hypothesis would be glue (or glue elements, like water), or possibly but less likely, oils from the teak, that has differential mobility in the maple due to structural effects in the wood, is causing the color effect. I'd love to be able get a sample under a microscope and even run a few mass spec / GC samples. Might be a learning moment.

[glenn bradley]

I notice that with end or edge grain. Never gave it much thought.

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[Sean Hagerty]

Did you use Mineral Oil on these? I don't see the discoloration in mine until I put the oil on, then as it soaks in, the darkening starts.

Why does it appear to be splotchy or not as prominent near the edges or in the middle? No clue, but take a piece of unglued maple scrap and rub your finish on it. I bet you see the same thing.

[Van Huskey]

I dunno but I actually think it looks cool...

[brian zawatsky]

That's happened to every end grain board I've made, regardless of species. Several dozen over the last couple years. I've also chalked it up to the glue. My hypothesis is that the glue is forced into the pores of the wood under pressure from clamping during lamination. This seals the pores around the edges of each block and prevents those areas from absorbing as much mineral oil as the center does, thus accounting for the difference in color. It's more noticeable on light colored woods, like maple.

[Chris Fournier]

Take a piece of your maple lumber and crosscut it. Do you see this colour variation in the raw lumber?

[Sam Blasco]

End grain is always interesting. The fibers act like a wick. I think you sanded too fine before applying the oil, closing things down and blocking some of the wicking action and getting variable penetration. Maple is tight and troublesome to begin with. Try going back and sanding only to 100 or 120 before adding the oil, then oil it several times over a couple of days, then wet sand with the oil as the lubricant in the 150 and 240 stages, and any subsequent stage sanding. Whenever I have an exposed end grain and want it to match the edge with the grain around the corner of a table top for instance, I will sand the end grain edge 3 times as fine as I do with the grain to block the wicking so that the end grain sides don't darken more than the two other edges.