# glueing plank



## bholland (Sep 10, 2018)

Hi all,

I am building a few table tops but also will need to combine boards. I need to fit together 2x6 boards (1.5x5.5 planks) for a workbench table top. I was thinking tongue and groove but I can't find a router bit that will handle that size board. My second thought was overlapping boards and just cutting like, a half inch or an inch section out of the planks. The last thought was dowels every foot or so.

For smaller boards, like 3/4 inch, I think tongue and groove will work well. Oh also, my router only accepts 1/4 inch shanks. That makes buying bits tricky but honestly, I won't buy a new router for this.


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## TomCT2 (May 16, 2014)

I simply rip them and edge glue.
there's a method you can use to rip both sides in one pass - this ensures the edges are parallel.

I've used 2x6 and 2x8; wider than that they like to cup.
these are 2x8


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## JIMMIEM (Oct 12, 2014)

How about using splines? Edge glueing should be enough but if you want reinforcement splines will run deeper than tongues and grooves.


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## bholland (Sep 10, 2018)

I did that with 2 boards out of 5 but I honestly wasn't sure if that was strong enough. For things like bookcases, I think I might do a tongue in groove but I guess edge gluing is sufficient for thicker boards? 

Splining is an interesting option. I do have a 1/4 inch and a half inch straight router bit. I could cut splines from board using my table saw. It would also teach me quite a lot. I will give it a try! Or maybe for this project, I will simply edge glue and move on. I just got worried because I looked up building table tops and they each said something like use a tongue in groove system, biscuits, or dowels. 

Thanks for your help!


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## Toolman50 (Mar 22, 2015)

JIMMIEM said:


> How about using splines? Edge glueing should be enough but if you want reinforcement splines will run deeper than tongues and grooves.


For an added bonus the splines help align your boards. 
I still prefer using splines even though I have a biscuit cutter. Splines are stronger than biscuits. But as a previous poster has said for 1 1/2” material you are safe to just butt joint your top. If joined with a good fit it will be strong.


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## epicfail48 (Mar 27, 2014)

Eh, a good edge-glue joint will be plenty strong enough for pretty much anything youd want to hit it with, strength really isnt a problem. Splines and the like really help with alignment more than anything. Unless youre planning to stand an elephant in the middle of a 24" span, just edge-glue


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## hawkeye10 (Feb 18, 2015)

I also agree with others that edge gluing the boards will be strong enough. If you still want to use splines make sure the grain on the splines is running opposite the grain of the boards. It will much stronger.


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## smitty10101 (Apr 1, 2017)

TomCT2 said:


> there's a method you can use to rip both sides in one pass -


How's that?
Can you please explain

Thks

:smile2:


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## Packard (Jul 27, 2018)

Edge glued boards make strong bonds. You only really need something for alignment. Either dowels with a center finding dowel jig or biscuits. Then glue and clamp. The bond will be stronger than the wood itself.


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## Tool Agnostic (Aug 13, 2017)

hawkeye10 said:


> I also agree with others that edge gluing the boards will be strong enough. If you still want to use splines make sure the grain on the splines is running opposite the grain of the boards. It will much stronger.


Do you glue the splines too? ... or only the edges of the boards?


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## TomCT2 (May 16, 2014)

smitty10101 said:


> How's that?
> Can you please explain
> Thks
> :smile2:



a flat parallel edge is best for gluing - using the table saw I rip both sides to get rid of the rounded corners. not infrequently the pc has a bow/etc, resulting in a gap.
I lay the two pcs side by side, tack a cleat on each end, then with the table saw blade just clearing the thickness, rip down the middle of the two pcs. ripping both in one pass, the blade kerf ensures they are parallel. once in a great while you have to do a second pass, if the gap is too wide.
starting with pcs that are 'too long,' after glue up, trim the ends so all the pcs are flush. that also removes any nail/screw holes (if that's an issue...for a workbench, not so much)
basic cleat idea (note double tack both sides so the pcs don't pivot)


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## GeorgeC (Jul 30, 2008)

epicfail48 said:


> Eh, a good edge-glue joint will be plenty strong enough for pretty much anything youd want to hit it with, strength really isnt a problem. Splines and the like really help with alignment more than anything. Unless youre planning to stand an elephant in the middle of a 24" span, just edge-glue



Absolutely correct. A good glue joint is strong as you are going to get. This has been proven by someone trying to break apart the glue joint and having the board break before the joint gave away.


George


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## FrankC (Aug 24, 2012)

TomCT2 said:


> a flat parallel edge is best for gluing - using the table saw I rip both sides to get rid of the rounded corners. not infrequently the pc has a bow/etc, resulting in a gap.
> I lay the two pcs side by side, tack a cleat on each end, then with the table saw blade just clearing the thickness, rip down the middle of the two pcs. ripping both in one pass, the blade kerf ensures they are parallel. once in a great while you have to do a second pass, if the gap is too wide.
> starting with pcs that are 'too long,' after glue up, trim the ends so all the pcs are flush. that also removes any nail/screw holes (if that's an issue...for a workbench, not so much)
> basic cleat idea (note double tack both sides so the pcs don't pivot)
> View attachment 366028


I like using this method, and take it one step further if making a panel.

Glue up pairs but don't cut the ends yet. You can then mate up the pairs using this method as well, trim the ends after entire panel is glued up.


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## Brian T. (Dec 19, 2012)

I've got a bunch of center-finding dowel jigs = just little aluminum mushrooms with a pointed top.
They work like a charm when I want to do a glue-up for a big wood carving, particularly a serving tray/dish.
Those are usually no more than 5/4, mosty 4/4 birch and 6" wide boards.
If the wood is at least 3" thick, I don't bother with pegs as there won't be any load like on a table top.

FrankC makes a very good point = don't glue up more than pairs (one seam).
Then you glue one paired unit to another (one seam again).


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## woodnthings (Jan 24, 2009)

*You need "perfect' alignment ......*



bholland said:


> Hi all,
> 
> I am building a few table tops but also will need to combine boards. I need to fit together 2x6 boards (1.5x5.5 planks) for a workbench table top. I was thinking tongue and groove but I can't find a router bit that will handle that size board. My second thought was overlapping boards and just cutting like, a half inch or an inch section out of the planks. The last thought was dowels every foot or so.
> 
> For smaller boards, like 3/4 inch, I think tongue and groove will work well. Oh also, my router only accepts 1/4 inch shanks. That makes buying bits tricky but honestly, I won't buy a new router for this.


The thicker the boards, the greater to glue bond strength is, BUT thinner boards like 3/4" will be plenty strong. I've even glued up 1/4" 
boards that are as strong as the wood itself. So, alignment is critical for two reasons. One, it will save material. and two it will reduce the amount of planing required, typically done by hand. A big mismatch will mean taking the entire surface down to level it out. The use of spines, biscuits or dowels will aide in aligning, but not so much, if it all for adding strength. I have used biscuits for aligning trim on table tops and splines for adding strength on mitered corners. 

I made a wide door from planks which would be identical in process as making a large table top:
https://www.woodworkingtalk.com/f2/door-build-2-xs-1-4-ply-55717/

Getting straight edges was a big part of the build and I used a different technique because the pieces were 7 ft long.


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## Toolman50 (Mar 22, 2015)

hawkeye10 said:


> I also agree with others that edge gluing the boards will be strong enough. If you still want to use splines make sure the grain on the splines is running opposite the grain of the boards. It will much stronger.


For all my splines I use a good grade of 1/4” plywood. 
I prefer blind splines (hidden). Never had a splined joint come apart.


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## TomCT2 (May 16, 2014)

the problem with splines / dowels / pins / t&g / etc is....if the board is slightly not straight, it's very easy to cut a straight joint in a warped board making for a lot of joint smoothing....

I batch plane all the pcs to a thickness, glue up two or three pcs to max planer width, take a real light cut for pretty and do the final glue up. 

meet my little alignment friend . . .









I normally prop it up in the web so it's grips evenly - this was a quick pose for illustration.


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## bholland (Sep 10, 2018)

Thanks for all the awesome tips! I ended up going with the edge glue method. Alignment isn't a huge problem for me. I aligned 1 edge flat with a board. I couldn't get perfect board lengths because I didn't have a stop (because I needed a workbench for the stop on the miter saw). As is, I am going to lose less than 1/8 of the table top, which I think is fairly good.

As for flatness, I am planing the edge of all of the boards using a #5 and finishing with a #7 AND using a 48-inch level. Any gaps that I see are very small and get compressed with the glue. I am flipping the boards based on grain and will eventually plane it flat. I opted for this path rather than going board by the board because the boards were actually fairly flat already. My guess is that I am going to lose about 1/8 to 1/4 inch on the board height, which is acceptable.

For the bookcases I need to build, I am probably going to use edge glue as well but dowel them to keep the longer boards equal heights when gluing, less for strength and more for ease of use. Also, I think I will use a plywood back for some serious strength and then groove the decorative board on top.


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## Packard (Jul 27, 2018)

TomCT2 said:


> a flat parallel edge is best for gluing - using the table saw I rip both sides to get rid of the rounded corners. not infrequently the pc has a bow/etc, resulting in a gap.
> I lay the two pcs side by side, tack a cleat on each end, then with the table saw blade just clearing the thickness, rip down the middle of the two pcs. ripping both in one pass, the blade kerf ensures they are parallel. once in a great while you have to do a second pass, if the gap is too wide.
> starting with pcs that are 'too long,' after glue up, trim the ends so all the pcs are flush. that also removes any nail/screw holes (if that's an issue...for a workbench, not so much)
> basic cleat idea (note double tack both sides so the pcs don't pivot)
> View attachment 366028


I've done the same but I used a few dabs of hot glue to join the planks. But the planks have to be straight within one width of the saw blade to make this work. If it is worse than that, he will have to use a straight edge to get the plank straight.


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## Littlefield (Sep 2, 2018)

TomCT2 said:


> a flat parallel edge is best for gluing - using the table saw I rip both sides to get rid of the rounded corners. not infrequently the pc has a bow/etc, resulting in a gap.
> I lay the two pcs side by side, tack a cleat on each end, then with the table saw blade just clearing the thickness, rip down the middle of the two pcs. ripping both in one pass, the blade kerf ensures they are parallel. once in a great while you have to do a second pass, if the gap is too wide.
> starting with pcs that are 'too long,' after glue up, trim the ends so all the pcs are flush. that also removes any nail/screw holes (if that's an issue...for a workbench, not so much)
> basic cleat idea (note double tack both sides so the pcs don't pivot)
> View attachment 366028





FrankC said:


> I like using this method, and take it one step further if making a panel.
> 
> Glue up pairs but don't cut the ends yet. You can then mate up the pairs using this method as well, trim the ends after entire panel is glued up.


Super slick. I’ve got lots of these to do.


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## ducbsa (Jul 6, 2014)

Toolman50 said:


> For all my splines I use a good grade of 1/4” plywood.


The actual thickness would need to be measured to choose the slot width, since plywood thickness varies.


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