# Biscuit joining and board thickness



## MN1987 (Mar 12, 2017)

Hi all -- I am making a dining room table using reclaimed barn wood boards (~2x6). They are nearly identical, except their thickness varies by about 4/16ths. I was planning on using a biscuit joiner to achieve a flat top. But is it also necessary to plane the boards down to uniform thickness before doing that? 

I used a standalone planer to plane the bottom side of one of the boards this weekend (I'm trying to preserve the patina on the table top), but soon discovered it would be slow, long process to do this for seven boards.

Is there a reason why I shouldn't biscuit them and then use shims to close up any gaps between any shallower boards and the table structure? This is what the underside of the table will look like.

Eric


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## Steve Neul (Sep 2, 2011)

A 1/4" is a pretty big difference. It would be in your best interest to make them uniform before you glue them together.

You don't really have to use biscuits for that. They only add a tiny bit of strength to the joint. What is needed is the edges jointed straight so the boards dry fit together well. When the joint fits well only glue is needed. 

How did you intend to attach the breadboard ends? It won't work to glue and biscuit the boards on the ends. The middle of the table is going to shrink in width and if you fasten boards to the ends solid it will prevent the middle from shrinking and the boards will split. A breadboard end is usually done with a tongue and groove joint and only glued in the center to allow for shrinkage. http://www.woodmagazine.com/woodworking-tips/techniques/joinery/breadboard


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## MN1987 (Mar 12, 2017)

Thanks. I was going to use the biscuits to ensure the top is completely flat, rather than for strength, per se. 

Perhaps my planer isn't sharp enough (it's a rental), but at the rate I'm going it would probably take two whole days to plane the boards down. It took an hour just to take 1/16th off one of the boards.

I'm skipping the breadboard ends because of what I've read on here and elsewhere. I'm just using longer boards.


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## FrankC (Aug 24, 2012)

Without the breadboard ends the difference in thickness will be visible at the end of the table, probably best to get them evened up somehow.


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## GeorgeC (Jul 30, 2008)

MN1987 said:


> Thanks. I was going to use the biscuits to ensure the top is completely flat, rather than for strength, per se.
> 
> Perhaps my planer isn't sharp enough (it's a rental), but at the rate I'm going it would probably take two whole days to plane the boards down. It took an hour just to take 1/16th off one of the boards.
> 
> I'm skipping the breadboard ends because of what I've read on here and elsewhere. I'm just using longer boards.


You have a planner problem. You should be able to take one pass on a 6' board in about a minute. (I am guessing here as I have never timed it, but feel that is approximately the time.) Take about 1/16" off at a time unless very hard wood.

George


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## Toolman50 (Mar 22, 2015)

The answer was is: yes, biscuits can align your top. 
Because you are using 2x6 lumber, I think a spline would work best. But the I prefer to use splines for something like a dining table. 
If you use biscuits, (or splines) without first planing the lumber evenly, your top will be flat but the bottom of the table will be uneven. Does that matter to you?


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## Serhij (Oct 26, 2018)

I picked up a lightly used Ryobi at the flea maket for $15. I wouldn't spend alot on one unless you plan on using it a whole lot.


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## GeorgeC (Jul 30, 2008)

old post


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## Danish Sethi (May 30, 2019)

For most portable plate joiners, a nominal 4 inch or 100 mm diameter blade is used for the #0, #10, #20 biscuit cuts. The blade is set deeper for joining the larger biscuits. Most blades have 4, 6, or 8 teeth and fit a 7/8 inch or 22 mm arbor.


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## GeorgeC (Jul 30, 2008)

MN1987 said:


> Thanks. I was going to use the biscuits to ensure the top is completely flat, rather than for strength, per se.
> 
> Perhaps my planer isn't sharp enough (it's a rental), but at the rate I'm going it would probably take two whole days to plane the boards down. It took an hour just to take 1/16th off one of the boards.
> 
> I'm skipping the breadboard ends because of what I've read on here and elsewhere. I'm just using l


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