# coffee table added width



## Cvbs (Jun 21, 2014)

Afternoon all,

Newbie here --- I am going to build a coffee table for my son. Unfortunately the 1x pine is only available in 24" width. I need it to be 32 inches. I am looking a tongue and grove the extra piece on to a side. My question is using t&g router bit kits or single bit? Any recommendations as to which way to go and particular manufactures? I am not looking at spending over $80 if at all possible. End results needs to be very tight seam.

If by chance you have a better solution I am allll ears ! :grin:

Tia,
cvbs
stay healthy and safe !


----------



## Stick486 (Jan 4, 2013)

blind spline it...
make the spline/slot approximately 1/3 the thickness of the material yur using for the top and at least 1/2'' deep...... 
*use a slotting bit....* - 20-25$...
another bit to consider - *A slotting cutter set....* a bunch of $$$

a true T&G bit won't give you as solid of a fit that a spline will..
a slot cutter will cost less...
use Baltic Birch for the spline...
the spline will be stronger than a T&G...
a spline will give you way more gluing surface
it's tough to blind a T&G joint...


----------



## DesertRatTom (Jul 3, 2012)

Agree with Stick, make a nice deep groove for a wide spline. I would cut the add on piece in half (rip) and put it on both sides. A solid piece that size will expand and contract and may want to warp over time. Adding to both sides will help with the warp, but if you attach this to the apron on bothsides, the expansion and contraction will tear the top apart over time. To handle that, you can firmly attach the top to one side and use table top attachment clips that allow for the expansion on the other, or use clips on both sides. Expansion is low in the long grain direction. These two suggestions will make a big difference over the years. Attached is a diagram of table parts and a pix of the clip. When cutting the groove for the spline, make sure all three pieces are face down on a router table, or if you do it with a table saw, you will need a tall fence to hold the thing steady while you cut, and you must have the pieces all facing the same direction. You can make a stopped groove so the spline doesn't show on the ends. I'd stop the groove about 2 inches from the ends of the top.

Gluing the three peices together in the spline and groove, and on the edges will increase the strength and warp resistance. Scrape the squeezed out glue off when it gets tacky or it will mess up your finish. Table top finish is really important, and if it were me, I'd sand it, then use a scraper for the final preparation for a really beautiful finish. Sanding actually abraids the surface. Scraping cuts the fibers clean so you get a smoother surface to start with than sanding.


----------



## Cherryville Chuck (Sep 28, 2010)

I am also a proponent of using splines. The grooves can also be cut on a table saw but the stock has to be flat. If there is any curve to it then a handheld router is better since it`s small base will follow the curve while maintaining an even distance from the face to the groove. 

The other advantage to using splines is that no wood is lost. With a T & G joint you lose some of the width when you machine the tongue. Essentially both are the same joint. One just has double grooves and the tongue is separate.


----------



## roxanne562001 (Feb 5, 2012)

I agree with Stick also. The other thing in my opinion setting up t and G cutters properly can be a PITA. The spline is easy to set up.


----------



## MEBCWD (Jan 14, 2012)

I agree with using a spline made of BB plywood and that would be my first choice of material for the spline. If you use solid wood make sure the spline material grain runs perpendicular to the joint grain. Several small pieces of spline can be used, it does not have to be one long strip. Just make sure when gluing that the surfaces of the board top are flat.

I also agree about adding to both sides so it helps even out stresses over time.


----------



## Stick486 (Jan 4, 2013)

Cherryville Chuck said:


> I am also a proponent of using splines. The grooves can also be cut on a table saw but the stock has to be flat. If there is any curve to it then a handheld router is better since it`s small base will follow the curve while maintaining an even distance from the face to the groove.
> 
> The other advantage to using splines is that no wood is lost. With a T & G joint you lose some of the width when you machine the tongue. Essentially both are the same joint. One just has double grooves and the tongue is separate.


the tongue is wider/thicker/deeper w/ a spline


----------



## DaninVan (Jan 1, 2012)

Just a shot in the dark here, but I'd guess hat Bill isn't thrilled about spending money on a sheet of 1/4" Baltic Birch(?) for what is essentially a simple project.
A 1/4" thick x 3/4" wide piece of maple or birch spline is not going to split over time if it's sound to start with. _The perpendicular grain concept is a big bonus for strength and stability._
Once it's clued in place, and the two panel pieces are butt glued and clamped it's going to be rock solid.
This whole plywood spline thing is a fairly recent idea in the history of furniture making. Most of our furniture is old even if not technically antique, although a lot of it is (antique). We've never had any instance of a glued panel separating, ever.
https://www.finewoodworking.com/2005/09/12/all-about-spline-joints
https://www.popularwoodworking.com/projects/inside-greene-and-greene-furniture/


----------



## Cvbs (Jun 21, 2014)

Everyone..,

Very much appreciate your input. Spline it is !  

Stick486
use a slotting bit.... is there a problem with using a 1/4 inch bit as opposed to 1/2"? ... Amazon has the 1/4 and I have an account there.
you mention a wood for the spline...Baltic Birch... specifically for strength? (not questioning Your wisdom, trying to build mine  )

all,
Specific wood glue recommendations?

I do appreciate ALL the help from the group... I probably will be asking MANY more questions as time goes on. 

tia,
Cvbs


----------



## Stick486 (Jan 4, 2013)

the original deal on splines... (see pics)
*DO NOT USE MASONITE/HARDBOARD* - VOE....
poor strength and it's fragile...

no BB ply??? use luan or high count ply plywood...
the omnidirectional grain imparts some serious strength...
ply is exceptionally stable...


----------



## Stick486 (Jan 4, 2013)

roxanne562001 said:


> I agree with Stick also. The other thing in my opinion setting up t and G cutters properly can be a PITA. The spline is easy to set up.


and cutting the grooves w/ the router resting on the face side pretty much takes care of flushing the surfaces...


----------



## Stick486 (Jan 4, 2013)

DaninVan said:


> Just a shot in the dark here, but I'd guess hat Bill isn't thrilled about spending money on a sheet of 1/4" Baltic Birch(?) for what is essentially a simple project.
> A 1/4" thick x 3/4" wide piece of maple or birch spline is not going to split over time if it's sound to start with. _The perpendicular grain concept is a big bonus for strength and stability._
> Once it's clued in place, and the two panel pieces are butt glued and clamped it's going to be rock solid.
> This whole plywood spline thing is a fairly recent idea in the history of furniture making. Most of our furniture is old even if not technically antique, although a lot of it is (antique). We've never had any instance of a glued panel separating, ever.
> ...


agreed...


----------



## Stick486 (Jan 4, 2013)

Cvbs said:


> Everyone..,
> 
> 1... Very much appreciate your input. Spline it is !
> 
> ...


1... good move...
2... do you mean shank diameters???
are you limited by collet/router size or that is all Amazon has???
me... I'd go w/ a ½'' shank.... more versatile and a wide full depth cut is brutal...
you could buy an arbor, bearings and cutters separate...
you *go to Acme*
change brands.. Whiteside and CMT are good bits...
how wide is your slot???
4... for panels.. weld bond.. Ace hardware carries it...
5... yur welcome...
6... ask away... we love questions...


----------



## Cvbs (Jun 21, 2014)

Danin Van,

No problem in spending,,, just educating myself as to the "Why" in the recommendation of the particular type of wood. I am sure the wife will have me finding plenty of good usages for the remainder if this works out well.!! hahaha Just trying to learn.

thanks for the information


----------



## Cvbs (Jun 21, 2014)

Stick486
is there a problem with using a 1/4 inch bit as opposed to 1/2"? ... meaning shaft. Amazon only offered the 1/4 shaft w/ 1/4 cut

Specific wood glue recommendations?...I have heard mention about a quick drying glue, (... thoughts???


----------



## Stick486 (Jan 4, 2013)

Cvbs said:


> Stick486
> is there a problem with using a 1/4 inch bit as opposed to 1/2"? ... meaning shaft. Amazon only offered the 1/4 shaft w/ 1/4 cut
> 
> Specific wood glue recommendations?...I have heard mention about a quick drying glue, (... thoughts???


No..
but a 1/2'' shank won't bend, deals w/ heat better and are like Timex watches...
buy the bit elsewhere...

on panels I use Weldbond... Ace hardware carries it...
no telling how much that top will be made to suffer..
plan for the worse...


----------



## Herb Stoops (Aug 28, 2012)

I guess I am the odd man out. I very seldom use splines and never had a failure in a table top. I just butt joint them and use Titebond II glue. If I splined every panel I made I would have gone crazy by now. Our wood working club went to several high end furniture plants and they turn out hundreds of panels ,and never spline them. Biscuit joint or Dowels are another easy way to go to get edge alignment. Heck I even see a lot of guys using pocket hole joints on flat panels now.
If I were doing this, I would just make a good edge joint and glue it. 

I like the idea of ripping the narrow piece and adding to both sides, When you do that be sure to run the grain in the same direction as the wide board. You may not see much difference until the finish goes on ,but then it will really stand out if the grains are in the opposite direction.

Herb


----------



## DaninVan (Jan 1, 2012)

Cvbs said:


> Danin Van,
> 
> No problem in spending,,, just educating myself as to the "Why" in the recommendation of the particular type of wood. I am sure the wife will have me finding plenty of good usages for the remainder if this works out well.!! hahaha Just trying to learn.
> 
> thanks for the information


Bill; the 1/4" ply is great for drawer bottoms and cabinet backs whatever the type (BB or domestic). Just be careful if you're buying other than Baltic Birch that the core layers are actually veneers, not particle board or similar. That sawdust filler is a ridiculous concept for something as thin as 1/4"...just my opinion.


----------



## Stick486 (Jan 4, 2013)

DaninVan said:


> Bill; the 1/4" ply is great for drawer bottoms and cabinet backs whatever the type (BB or domestic). Just be careful if you're buying other than Baltic Birch that the core layers are actually veneers, not particle board or similar. That sawdust filler is a ridiculous concept for something as thin as 1/4"...just my opinion.


¼'' BB isn't ¼''... it's 6mm...

.


----------



## DaninVan (Jan 1, 2012)

Not really my point, but thanks for the clarification, Stick.


----------



## Stick486 (Jan 4, 2013)

DaninVan said:


> Not really my point, but thanks for the clarification, Stick.


okay...
what did I miss???
what was the point...

I best go take a nap...


----------



## Cherryville Chuck (Sep 28, 2010)

Cvbs said:


> Stick486
> is there a problem with using a 1/4 inch bit as opposed to 1/2"? ... meaning shaft. Amazon only offered the 1/4 shaft w/ 1/4 cut
> 
> Specific wood glue recommendations?...I have heard mention about a quick drying glue, (... thoughts???


When using splines you want to be able to get the glue in quickly and the spline in and both boards together and clamped. If it's something very small you are okay with a faster drying glue. The bigger the project the longer it will take and it's better for a glue with long open time. One other thing that happens when you add glue is that the water in it causes to wood to start swelling up. If you take too long fitting parts together that can be a real problem. A plywood spline would be less prone to swell I think but you still want to make it quick.

One other issue when you glue parts like this together is that you don't want to finish sand it right away while the wood is still swelled up. If you sand it right away you could end up with a depression once the wood completely dries.


----------



## Stick486 (Jan 4, 2013)

Cherryville Chuck said:


> When using splines you want to be able to get the glue in quickly and the spline in and both boards together and clamped. If it's something very small you are okay with a faster drying glue. The bigger the project the longer it will take and it's better for a glue with long open time. One other thing that happens when you add glue is that the water in it causes to wood to start swelling up. If you take too long fitting parts together that can be a real problem. A plywood spline would be less prone to swell I think but you still want to make it quick.
> 
> One other issue when you glue parts like this together is that you don't want to finish sand it right away while the wood is still swelled up. If you sand it right away you could end up with a depression once the wood completely dries.


the weldbond has a 2~3x's longer open time than TB..
doesn't plasticize w/ heat like TB does...
it IS waterproof...
if it dries on your applicator brush, the brush is done for...
if TB dries on your brush just run the brush under hot tap water.. the dried glue will wash right out...

years and years ago I built a loooooong coffee table using TB.. (TB is relabelled Franklin)
I had to go back and remake the top because the original separated - twice...
turned out the table sat in the sun all day.. the sun heated up the top, the glue plasticized and the butt joints crept...

the validation to this was to make two butt joint panels... 1 w/ TB and 1 w/ WB...
put them in a closed up truck that sat in the sun...
the TB panel joints opened..
the WB panel stayed together... 
the same test w/o splines; the TB panel fell completely apart....

since this was a recall for the table... that was money out of pocket..
that table was last time I made a no spline PVA butt joint...
and that was the end of the recalls for like issues...


----------



## ger21 (Feb 10, 2019)

Herb Stoops said:


> I guess I am the odd man out. I very seldom use splines and never had a failure in a table top. I just butt joint them and use Titebond II glue.



I agree 100%. An edge glued joint is stronger than the wood itself if done properly. A splined joint is actually weaker. The only reason to use a spline is for alignment.
For glue, just regular titebond is fine.


----------



## Herb Stoops (Aug 28, 2012)

ger21 said:


> I agree 100%. An edge glued joint is stronger than the wood itself if done properly. A splined joint is actually weaker. The only reason to use a spline is for alignment.
> For glue, just regular titebond is fine.


Biscuits or dowels are a heck of a lot faster and less messy than a spline in my opinion for alignment. I am not saying it is the only way, there are more than a few ways to glue up panels, I just say do what is more comfortable for you. I learned in 1952 shop where we used weldwood powder glue mixed with water, and jointed the edges with hand planes to glue up panels, and it has always worked for me.
HErb


----------



## Stick486 (Jan 4, 2013)

ger21 said:


> I agree 100%. An edge glued joint is stronger than the wood itself if done properly. *A splined joint is actually weaker. The only reason to use a spline is for alignment.*
> For glue, just regular titebond is fine.


I disagree w/ that...
a spline is a variation of a M&T joint...
so you're saying that a M&T joint is weaker than a butt joint also...

so all we need to do is butt glue the table apron to the legs because it will be stronger than a time tested and proven M&T....
good luck w/ that...


----------



## Nickp (Dec 4, 2012)

ger21 said:


> I agree 100%. An edge glued joint is stronger than the wood itself if done properly. A splined joint is actually weaker. The only reason to use a spline is for alignment.
> For glue, just regular titebond is fine.



Gerry, I'm not sure of your experiences but a spline joint IS NOT weaker than an ordinary butt or edge joint. It just isn't. While a butt joint may be appropriate for certain applications and may be sufficient in that application it is not stronger than a spline joint. Spline joints are specifically used for their strength and not intended for alignment only, although they may be used as such. When alignment only is required dowels or biscuits may be used...but add a breadboard to a table and you'll want to use a spline joint. One important thing to remember is the spline grain must run perpendicular to the joint, otherwise it is no stronger than a regular butt/edge joint.

And in certain applications such as exterior joints exposed to weather, Titebond may fail where Weldbond will not. Extreme heat is a good example, furniture in the sun of a window is another example.

I would recommend you try some spline joints versus butt/edge joints and try it yourself. I think you will retract your statement that a spline joint is weaker than a butt joint.

No offense intended...I just think you'll be alone in the crowd...


----------



## Herb Stoops (Aug 28, 2012)

@Nickp
Most cutting boards are used in wet conditions and glued with TB II and washed off daily with warm water and soap and chopped on with a chef knife or cleaver. That is more abuse than a table top gets with a 3-4 coat finish on it. I still think Splines have their place but they are also overkill and don't need to be used every case. Also when you talk breadboard ends you are talking about something entirely different, that is end grain against side grain.
Herb


----------



## Cherryville Chuck (Sep 28, 2010)

ger21 said:


> I agree 100%. An edge glued joint is stronger than the wood itself if done properly. A splined joint is actually weaker. The only reason to use a spline is for alignment.


I have to disagree Gerry and the following diagram I drew shows why. A straight butt joint is susceptible to tensile shear (straight apart) and particularly to angular shear since it acts as both a lever and is focused at either the top or bottom edge instead of the entire glue line.

A spline increases the amount of glue surface and adds shear lines that require the glue to fracture directly along the glue line instead of 90* to it. It's similar in principle to adding rebar to concrete.

In both cases I didn't add arrows indicating a vertical failure where one side goes up while the other goes down. In the straight butt joint you would have to shear the entire glue line along it's length. In the spline joint you would have to do the same plus shear the spline off. Either one of those cases are unlikely.

So it doesn't just aid in alignment, it makes the joint much stronger. Besides increasing the amount of glue surface it also helps resist angular stress to the glue line which is the one that is most prone to cause joint failure.


----------



## DaninVan (Jan 1, 2012)

And as far as the grain direction* with a plywood spline * goes, since the veneers are perpendicular to each other the face grain direction shouldn't really have any significant effect on the joints' strength. I'm not saying it has none, but the benefit to having the face grain perp. to the butt joint as opposed to parallel to it should be measurable only under Eng. lab testing conditions, if any exist at all.


----------



## Nickp (Dec 4, 2012)

Herb Stoops said:


> @Nickp
> Most cutting boards are used in wet conditions and glued with TB II and washed off daily with warm water and soap and chopped on with a chef knife or cleaver. That is more abuse than a table top gets with a 3-4 coat finish on it.* I still think Splines have their place but they are also overkill and don't need to be used every case.* Also when you talk breadboard ends you are talking about something entirely different, that is end grain against side grain.
> Herb



No argument there, Herb. Gerry posted that spline joints are weaker than butt/edge joints...that just isn't the case. In my post I did say that butt/edge joints are sufficient for some applications. These would be where no support or stress is required at the joint and where only alignment is required. Having said that, if I were to be joining boards for a table top or cabinet doors, a spline joint is what I would use and recommend.

As for the glue, I cited exterior environments and high heat applications. For example, I would not use TBII to butt/edge outside cedar/teak/redwood furniture applications. A cutting board doesn't take the same abuse with a daily washing.

So yes, a spline joint can be overkill...but, it is not weaker than a plain ole butt/edge joint...and, just an opinion here, it is so easy to make it's not worth the trouble to dig out the biscuit or dowel cutting gear.


----------



## Nickp (Dec 4, 2012)

DaninVan said:


> And as far as the grain direction* with a plywood spline * goes, since the veneers are perpendicular to each other the face grain direction shouldn't really have any significant effect on the joints' strength. I'm not saying it has none, but the benefit to having the face grain perp. to the butt joint as opposed to parallel to it should be measurable only under Eng. lab testing conditions, if any exist at all.


Good point on plywood splines...so much easier to cut up strips of 1/4" ply than to make 'em with scrap...:smile:

As to grain direction of the spline itself, I would think parallel grain would not make the joint any stronger than glued tongue n groove. Mortise and tenon comes to mind.


----------



## Stick486 (Jan 4, 2013)

Nickp said:


> Good point on plywood splines...so much easier to cut up strips of 1/4" ply than to make 'em with scrap...:smile:
> 
> As to grain direction of the spline itself, I would think parallel grain would not make the joint any stronger than glued tongue n groove. Mortise and tenon comes to mind.


as you look at the top veneer of plywood look to the grain orientation...
no rip a strip off the ply.. cross cut an equal sized strip...
now play w/ them.. bend/twist and what not...
you'll find the cross cut to be more flexible lengthwise than the rip... 
but the long grain of the cross cut doesn't flex/bend hardly at all...
the ripped piece flexes the opposite to the cross cut piece...

there is a reason plywood's long grain is installed perpendicular to joists and rafters... it's strongest in that orientation...


----------



## Herb Stoops (Aug 28, 2012)

And the plywood end grain looks "odd",crappy, and stands out when finished ,where as solid wood looks more professional,IMHO.

HErb


----------



## Cherryville Chuck (Sep 28, 2010)

Herb Stoops said:


> And the plywood end grain looks "odd",crappy, and stands out when finished ,where as solid wood looks more professional,IMHO.
> 
> HErb


It does look odd but you can machine stopped grooves so that the ends of the groove won't show. I usually do that so that I can leave a small gap behind the spline to make the fit easier and that would show at the ends. In that case the plywood is fine. Neither the butt joint or the spline joint are likely to shear straight up and down but the spline adds a lot of glue surface and it resists the joint pulling apart so for that plywood works just fine. And if you do have the ends showing then just add solid wood at the ends and plywood in the middle.

You can also use contrasting wood when it is going to show and that can look really sharp.


----------



## Stick486 (Jan 4, 2013)

Herb Stoops said:


> And the plywood end grain looks "odd",crappy, and stands out when finished ,where as solid wood looks more professional,IMHO.
> 
> HErb


do blind splines...


----------



## Herb Stoops (Aug 28, 2012)

Stick486 said:


> do blind splines...


Just added one more step,Mr. Efficiency.


----------



## DaninVan (Jan 1, 2012)

Just slip a strip of 1/4" Aluminum in there, pop-rivet it and call it a day...


----------



## Stick486 (Jan 4, 2013)

Herb Stoops said:


> Just added one more step,Mr. Efficiency.


did not...


----------



## Stick486 (Jan 4, 2013)

Herb Stoops said:


> Just added one more step,Mr. Efficiency.


start the groove late and end it early...
cut the spline to length as required...


----------



## DaninVan (Jan 1, 2012)

DaninVan said:


> Just slip a strip of 1/4" Aluminum in there, pop-rivet it and call it a day...


Actually...substitute brass and epoxy it in; should look elegant from the end view.


----------



## 1fizgig (Feb 11, 2018)

You wouldn't need to go all the way out to the edge with the spline would you? Surely you'd terminate it say 10mm back from the end? That would keep the piece looking tidy.

And what about splitting the splines up - say over a 1 metre length if you did 3 x 300mm splines, would that be okay? Just fishing for thoughts here, on a 1m joint I'd probably do a single spline, but you get the idea of what I'm asking.


----------



## ger21 (Feb 10, 2019)

Sorry, but you guys are all wrong. 

If you don't believe me, how about The Wood Whisperer? his first reply here mentions splines being weaker.
https://www.thewoodwhisperer.com/articles/does-a-glue-line-bit-add-strength-to-a-joint/

Google just found me numerous other sites and pages that back me up.
How about Christopher Schwarz? Read the second paragraph.
https://www.popularwoodworking.com/woodworking-blogs/in-defense-of-splines-grooves-biscuits-dominos/




> Gerry, I'm not sure of your experiences


25+ years working in a cabinet shop.




> I disagree w/ that...
> a spline is a variation of a M&T joint...
> so you're saying that a M&T joint is weaker than a butt joint also...


Ever seen a mortise and tenon where the grain in both boards runs the same direction. No, because it would have no strength. A spline and M&T is comparing apples to oranges.



> I have to disagree Gerry and the following diagram I drew shows why. A straight butt joint is susceptible to tensile shear (straight apart) and particularly to angular shear since it acts as both a lever and is focused at either the top or bottom edge instead of the entire glue line.
> 
> A spline increases the amount of glue surface and adds shear lines that require the glue to fracture directly along the glue line instead of 90* to it. It's similar in principle to adding rebar to concrete.


Say you have 3/4" thick boards. 
With a butt joint, you have a 3/4" thick glue line. 
If you were to add a 1/4" spline, you'd have two 1/4" glue joints. Which is stronger?

Yes, the spline can potentially add more glue surface, in a perfect world. But that would require the spline to be so tight, that you wouldn't be able to get the joint together.
If there are any spaces between the spline and the slot (even a few thousandths of an inch), the joint will be weaker.

You clamp everything you glue together, correct? But I bet your splines are not tight enough to need clamps to force them in the slots. And if they are not that tight, then they aren't as strong.

Splines have their places, but adding strength to edge glued boards is not one of them.


----------



## Stick486 (Jan 4, 2013)

1fizgig said:


> You wouldn't need to go all the way out to the edge with the spline would you? Surely you'd terminate it say 10mm back from the end? That would keep the piece looking tidy.
> 
> *And what about splitting the splines up - say over a 1 metre length if you did 3 x 300mm splines,* would that be okay? Just fishing for thoughts here, on a 1m joint I'd probably do a single spline, but you get the idea of what I'm asking.


yes on the slot termination.. 
fine on the segmented spline......


----------



## DaninVan (Jan 1, 2012)

Gerry; there's so many debatable asumptions in your reply that I don't know where to start.
1) glue ups are NOT supposed to be tight fits. The glue itself needs space or it'll just squeeze out (glue starved is the expression i think).
2) your arithmetic on the spline joint is incorrect, The plain butt joint is 3/4" x length. The spline joint is (at least) 1/2" for the face plus 3(1/4")x2 for the spline., so basically almost 3x the glued surface of the butt joint.
3) the spline material, if installed with the grain perpendicular, _can not_ be cracked. It simply has _no_ room in which to flex. You'd have to drive your pickup across the panel to crack it, and most likely if it's lumber as opposed to plywood, the boards would split before the joint. Once again, modern glues are not getting the credit they deserve. A properly splined and glued joint is not going to separate. Period.


----------



## Nickp (Dec 4, 2012)

@ger21

Sorry, Gerry...I was not referring to your years of experience in a cabinet shop...I was referring to your experiences with spline joints. A lot of people go through a lifetime and never enjoy the pleasure of using spline joints...

Couple of comments on your references...
1. Wood Whisperer...he freely admits that his feelings are purely "theoretical"
2. Christopher Schwarz...he states "could weaken" but does not clarify under what circumstances. He also freely admits to using "alignment aids" for table tops...different discussion than comparing splines to butt/edge joints. He does state that under certain circumstances there is no need for the additional strength...implying that the spline will offer additional strength.

One advantage of using splines over T&G is the ability to make the grooves deeper. This provides additional surface area for the spline. So using a 1" wide spline strip offers 1/4+1/4+1/2+1/2+1/4 of glue area. Combined with grain running perpendicular to the edge and one cannot believe it will be weaker than a butt joint.

There are better references than what you posted that specifically state the strength of the spline joint as being stronger than butt or edge/edge joints.

All I ask is for you to try some at some appropriate time...I believe you will change your mind about splines.


----------



## Herb Stoops (Aug 28, 2012)

I'm on Gerry's side of this one.
I made a dining room truss table 42WX92 years ago out of clear fine grained 5/4 pine for my son in NM. I live in WA and I made it in the summer and took it to him in late Sept unfinished. It was glued up with butt joints made from 5/4 X 8' boards. He stained and finished the table and set it up in the big dining room. about 3 months later he called me and said the table had a crack near the center, not in the joint,but in the middle of a board. the change in climate was too much for the table,but the glue joints held. His new house was an adobe style where the inside is stucco like plaster walls with the solid wood headers over the doors and windows. These crack and twist as they age,and gives it the "Desert" look. 
The table cracked, but the glue held.
Herb


----------



## ger21 (Feb 10, 2019)

> All I ask is for you to try some at some appropriate time...I believe you will change your mind about splines.


I've probably used more splines than you over the years. But never to add strength to an edge glued joint.



> glue ups are NOT supposed to be tight fits. The glue itself needs space or it'll just squeeze out (glue starved is the expression i think).


Titebond recommends 100psi (softwoods) to 250psi (hardwoods) clamping pressure for their glues. 
That's potentially 9000 pounds of force on a 3/4" x 48" joint. That's not a tight fit?


----------



## Nickp (Dec 4, 2012)

Obviously we've had different experiences...and after all, that's what we base our decisions on.

How about we agree to disagree...? Neither one of us will concede to the other's point anyway.

And if I haven't presented it clearly, I have not been trying to make the point that splines are to be used in all applications...only responding to your point that a spline joint is weaker than a butt/edge joint.


----------



## DaninVan (Jan 1, 2012)

Herb Stoops said:


> I'm on Gerry's side of this one.
> I made a dining room truss table 42WX92 years ago out of clear fine grained 5/4 pine for my son in NM. I live in WA and I made it in the summer and took it to him in late Sept unfinished. It was glued up with butt joints made from 5/4 X 8' boards. He stained and finished the table and set it up in the big dining room. about 3 months later he called me and said the table had a crack near the center, not in the joint,but in the middle of a board. the change in climate was too much for the table,but the glue joints held. His new house was an adobe style where the inside is stucco like plaster walls with the solid wood headers over the doors and windows. These crack and twist as they age,and gives it the "Desert" look.
> The table cracked, but the glue held.
> Herb


You're more in-the-middle-of-the-road, Herb. You've just reinforced my point about modern glues not being given enough credit. You haven't implied that splines in butt joints are weaker.
The only way this controversy could be put to bed is if, as I first stated, it was objectively tested in an Engineering lab. under controlled conditions.
Anyways, good chat.


----------



## Herb Stoops (Aug 28, 2012)

DaninVan said:


> You're more in-the-middle-of-the-road, Herb. You've just reinforced my point about modern glues not being given enough credit. You haven't implied that splines in butt joints are weaker.
> The only way this controversy could be put to bed is if, as I first stated, it was objectively tested in an Engineering lab. under controlled conditions.
> Anyways, good chat.


Yeah ,Dan, I guess your right, I have done both and not because one was stronger than the other. On the workbench I made out of a 1 3/4" thick 9' long solid core door, ( it was a cut out for glass, so there were no solid rails and styles on it), I added a 2" wide X 1 3/4" thick white oak edge. It was attached with glue and 3 1/2"long screws @ 12" o.c. The core on the door was just a course Particle Board And the wood was just glued and screwed to that. I used that bench for years clamping to it and it never budged.

HErb


----------



## Cherryville Chuck (Sep 28, 2010)

ger21 said:


> Sorry, but you guys are all wrong.
> 
> If you don't believe me, how about The Wood Whisperer? his first reply here mentions splines being weaker.
> https://www.thewoodwhisperer.com/articles/does-a-glue-line-bit-add-strength-to-a-joint/
> ...


I didn't see either article say that a spline joint was weaker, only that it wasn't necessary



> Say you have 3/4" thick boards.
> With a butt joint, you have a 3/4" thick glue line.
> If you were to add a 1/4" spline, you'd have two 1/4" glue joints. Which is stronger?


The spline. You are ignoring the shear planes and extra glue on the spline. Go back and look at my diagram again. You won't shear either joint apart by pushing one side up and the other down because you are trying to shear the joint along the glue line. That's just about impossible. However, you can get the butt joint to fail if you apply angular torque on it because most of that force is applied close to one edge. It's like you are levering on the joint. Twist will cause it to fail for similar reasons. The spline resists that because it has shear lines along the faces of the spline that would require them to be sheared along the glue lines. As in trying to shear the butt joint with straight vertical displacement that is virtually impossible. With the spline joint you have the shear lines along the vertical plane of the butt joint PLUS the shear lines which are 90* to that. Just like I stated before that is similar to what rebar does for concrete.



> Yes, the spline can potentially add more glue surface, in a perfect world. But that would require the spline to be so tight, that you wouldn't be able to get the joint together.
> If there are any spaces between the spline and the slot (even a few thousandths of an inch), the joint will be weaker.
> 
> You clamp everything you glue together, correct? But I bet your splines are not tight enough to need clamps to force them in the slots. And if they are not that tight, then they aren't as strong.
> ...


Sorry but don't you try and fit joints like that so that you leave just enough room for the glue? That's what you do for an M & T joint. If it's too tight you can wipe the glue off the parts pushing it together. Too loose and you'll get a weak joint. I'm afraid those last arguments don't make much sense Gerry.

By the way, I majored in physics and I am also a ticketed steam engineer. One thing I am very good at is force vectors. Like I said, go back and look at my diagram again. It should be self explanatory. A butt joint might be plenty good enough but there is no way that it is stronger than a spline joint. The diagram I drew proves it.


----------



## bfblack (May 2, 2012)

Wow!! This has been an interesting read even though the topic drifted. There are more opinions than contributors. I did not understand why butt and edge joints got mentioned in the same sentence as they require different treatments. I thought a butt joint was end grain to either face grain or end grain. A lot of the discussion boils down to "my joint is stronger than your joint" with often times no supporting experimental evidence. I like to ask the questions "is the joint strong enough for the intended purpose" and "do I have the tools to make this joint". Here are some resources on joint testing that I found informative.

Matthias Wandel: https://woodgears.ca/joint_strength/dowel.html (This guy has done a lot of good work on numerous woodworking topics.)

Bruce Gray, “Testing Joints to the Breaking Point”, FWW # 148, March/Apr 2001, pp 74-79. (Note that this article is not available in the FWW archives because of a copyright issue. Find someone that has the original magazine.)

Douglas Moore and Thomas McKenna, “Joinery Shootout”, FWW # 203, January/February 2009, pp 36-41.

Most joint failures in the above resources were away from the glue line indicating that the glue is stronger than the parent wood.


----------



## DaninVan (Jan 1, 2012)

Guilty as charged, Ben; I was calling them "butt" joints instead of "edge" joints as well.


----------



## Stick486 (Jan 4, 2013)

one thing about dowelled joints...
nobody ever tests a dowelled joint that been in place for an extended period of time...
always brand new ones..
I can't recall ever recall meeting a dowelled joint that hadn't loosened over time...


----------



## Cherryville Chuck (Sep 28, 2010)

A dowel joint is just another form of mortise and tenon joint where the tenon is free floating. Instead of the tenon and mortises being rectangular (more or less) they're round and usually much smaller. That is one of the factors that make it weaker and the other is the dowel material. I bought some dowels last year that are so soft I can easily snap them in half. If I made my own from oak or birch that would be a different story. Maybe the reason you've had them come loose Stick is the way they were glued or maybe they were too tight for the hole and wiped all the glue off on the way in. When you are drilling a hole and sticking a pre-made dowel in it you don't have the same control over the fit like you do an M & T joint.


----------



## Stick486 (Jan 4, 2013)

Cherryville Chuck said:


> A dowel joint is just another form of mortise and tenon joint where the tenon is free floating. Instead of the tenon and mortises being rectangular (more or less) they're round and usually much smaller. That is one of the factors that make it weaker and the other is the dowel material. I bought some dowels last year that are so soft I can easily snap them in half. If I made my own from oak or birch that would be a different story. Maybe the reason you've had them come loose Stick is the way they were glued or maybe they were too tight for the hole and wiped all the glue off on the way in. When you are drilling a hole and sticking a pre-made dowel in it you don't have the same control over the fit like you do an M & T joint.


no, not my dowelled joints, I don't do dowels...
I talking about older DJ's in chairs and what not...
true M&T's are a different story... M&T are some strong joints...
same for a spline...
every so often broken DJ's...
Broken M&J's happened, but were a lot rarer......
ever wonder why splined miters are so highly recommended???...

*https://woodworkingformeremortals.com/super-strong-splines-miter-joints/
https://www.woodworkersjournal.com/build-strong-miter-joints-splines/
https://www.wooden-box-maker.com/miter-joints.html
https://www.djmarks.com/davids-blog/archive-articles/splined-miters-by-david-j-marks/

https://woodworking.stackexchange.c...han-a-miter-but-still-look-like-a-miter-joint*


----------



## thomas1389 (Jan 4, 2012)

All this talk about joints is making my head spin. I was using joints long before they were legal and I never got broke. Ever! It was to be considered the best of times.


----------



## DaninVan (Jan 1, 2012)

"I was using joints long before they were legal and I never got *broke*."
-Thomas

Busted maybe?


----------



## thomas1389 (Jan 4, 2012)

DaninVan said:


> "I was using joints long before they were legal and I never got *broke*."
> -Thomas
> 
> Busted maybe?


Nope. Never close. Somewhat lucky in those days. The good ole days, when you're young, invincible and stupid.


----------



## DaninVan (Jan 1, 2012)

I'm going for two oughta three...


----------



## Nickp (Dec 4, 2012)

DaninVan said:


> I'm going for two oughta three...



Now you got me thinking which one I would throw out...tough choices...:grin::grin::grin:


----------



## Stick486 (Jan 4, 2013)

DaninVan said:


> I'm going for two oughta three...


I'm w/ you...


----------



## Stick486 (Jan 4, 2013)

thomas1389 said:


> Nope. Never close. Somewhat lucky in those days. The good ole days, when you're young, invincible and stupid.


and got the scars to prove it...


----------



## Cherryville Chuck (Sep 28, 2010)

Stick486 said:


> no, not my dowelled joints, I don't do dowels...
> I talking about older DJ's in chairs and what not...
> true M&T's are a different story... M&T are some strong joints...
> same for a spline...
> ...


Another good joint for picture frames is a mitered half lap. But if you don't want the lap to show on the sides then you have to make it a stopped half lap and stay back from the edge a little. It gets a bit tedious to do then but it's even stronger that the splined miter.


----------



## Stick486 (Jan 4, 2013)

these joints??? (I believe the 1st one is a bridle)
dado blade to the rescue...

.


----------



## Stick486 (Jan 4, 2013)

this one has a lot of merit especially in the aesthetics department...
I can see this one as double or even a triple face keyed.... and splined...

.


----------



## DaninVan (Jan 1, 2012)

Nickp said:


> Now you got me thinking which one I would throw out...tough choices...:grin::grin::grin:


The "young" ship has sailed...


----------



## Stick486 (Jan 4, 2013)

DaninVan said:


> The "young" ship has sailed...


that ship sank a long time ago...


----------



## TWheels (May 26, 2006)

So Tongue and Groove joints ruled out in this situation, as are dowels and biscuits. 
So when are tongue and groove joints appropriate?


----------



## Stick486 (Jan 4, 2013)

flooring..
re-entrant angles...
wainscot...
parquetry..
sheathing..
panelling..
camouflage beaded board joints...
plank core...
concrete forms...


----------



## Cherryville Chuck (Sep 28, 2010)

Stick486 said:


> these joints??? (I believe the 1st one is a bridle)
> dado blade to the rescue...
> 
> .


The diagram not the picture. Would you call the picture a double bridle or double lap bridle? That one should be the strongest of all.


----------



## Stick486 (Jan 4, 2013)

Cherryville Chuck said:


> The diagram not the picture. Would you call the picture a double bridle or double lap bridle? That one should be the strongest of all.


one blade/tenon w/ one socket/mortise = a single...
bridle joints are used widely in timber framing...
a tusk tenon is a bridle...
With the bridle joint, the mortise runs the full depth of the tenon meaning end grain of the tenon shows and with a traditional mortise and tenon the tenon is blind.
there are so many configurations for this joint it's almost unreal...

here's a single w/o the miter...










another single w/ miter..










through double and half blind double w/o miter....










a T bridle...


----------



## Stick486 (Jan 4, 2013)

Cherryville Chuck said:


> The diagram not the picture. Would you call the picture a double bridle or double lap bridle? That one should be the strongest of all.


just a double...
agreed on the strongest...


----------



## ger21 (Feb 10, 2019)

How exactly does this joint work?????


----------



## Stick486 (Jan 4, 2013)

ger21 said:


> How exactly does this joint work?????


same way as these two...


----------



## ger21 (Feb 10, 2019)

That's not what I'm seeing.


----------



## DesertRatTom (Jul 3, 2012)

For that joint to work the end cut of the tennon must be perpendicular to the grain of the wood, and this when redone would have a reverse miter on the corner. Just plain wierd.


----------



## Stick486 (Jan 4, 2013)

ger21 said:


> How exactly does this joint work?????


my bad...
thanks for pointing out that poor depiction...
it's been corrected...


----------



## Cherryville Chuck (Sep 28, 2010)

The bridle joint was the only type I remember seeing on the old counter-weighted sash windows. You remember the ones where every so often the cord attached to the weight would break and you'd hear the counterweight drop. Then it was a stick to keep the window open until someone got around to removing the molding and replacing the cord. It was common on door corners at the same time. It ws capable of with standing racking forces better than other joints.


----------



## Stick486 (Jan 4, 2013)

Cherryville Chuck said:


> The bridle joint was the only type I remember seeing on the old counter-weighted sash windows. You remember the ones where every so often the cord attached to the weight would break and you'd hear the counterweight drop. Then it was a stick to keep the window open until someone got around to removing the molding and replacing the cord. It was common on door corners at the same time. It ws capable of with standing racking forces better than other joints.


what???
no counter weight access doors..
or you didn't use jack chain....


----------



## DaninVan (Jan 1, 2012)

No and no.
Up here, exclusively braided sash cord and if there was an access at the time of installation, after half a century long covered over.
All I ever did on reno/repairs was remove the side trim mouldings which gave immediate access to the sash weights.

Double hung sash were the windows of choice up here, with the occasional side-hung awning style thrown in.


----------



## Stick486 (Jan 4, 2013)

DaninVan said:


> No and no.
> Up here, exclusively braided sash cord and if there was an access at the time of installation, after half a century long covered over.
> All I ever did on reno/repairs was remove the side trim mouldings which gave immediate access to the sash weights.
> 
> Double hung sash were the windows of choice up here, with the occasional side-hung awning style thrown in.


no and no...
pulley was intended for chain...
and a big time no on the casing removal...
not after a bazillon coats of oil base were put on it and the floated in plaster top coat... (precaulk days)...


----------



## DaninVan (Jan 1, 2012)

You say tomato... 
Too late now; 35 yrs of doing it my way. 
In retrospect, now that I think back on it, the plasterers used the window jamb as a ground and completed the plastering prior to the trim being applied. But yes, the buildup of paint was a concern.
Far more of a problem was the cross nailed mitered corners; they were a nightmare to get apart without damaging the trim.


----------



## Stick486 (Jan 4, 2013)

DaninVan said:


> You say tomato...
> Too late now; 35 yrs of doing it my way.


talk about stuck in a rut....
but no problemo...
we'll retrain ya to do it the right way...
there's hope for ya yet...


----------



## TWheels (May 26, 2006)

ger21 said:


> How exactly does this joint work?????


I do not see how this depiction is even a joint. To me each is a part of a joint of which the other is not a part.


----------



## TWheels (May 26, 2006)

Stick486 said:


> flooring..
> re-entrant angles...
> wainscot...
> parquetry..
> ...


Thank you very much @Stick486. 

I wonder, is there a need for a document or sticky discussion of types of joints, relative strengths, how to construct them, etc?
i


----------



## Stick486 (Jan 4, 2013)

have at it...


----------



## Cherryville Chuck (Sep 28, 2010)

TWheels said:


> Thank you very much @Stick486.
> 
> I wonder, is there a need for a document or sticky discussion of types of joints, relative strengths, how to construct them, etc?
> i


Tage Frid's first book. It takes a little bit of reading to understand the format but it is a step by step account of how to make every common joint there is. For woodworkers this book should be considered a national treasure. https://www.amazon.ca/s?k=tage+frid+joinery+,+tools,+and+techniques&i=stripbooks&ref=nb_sb_noss I found my copy in really good used condition for a few bucks. They are often sold on ebay too and you may find it cheaper there.


----------



## MEBCWD (Jan 14, 2012)

ger21 said:


> How exactly does this joint work?????


Turn over the piece on the left and it fits into the piece on the right.


----------



## Nickp (Dec 4, 2012)

TWheels said:


> I do not see how this depiction is even a joint. To me each is a part of a joint of which the other is not a part.




If I'm not mistaken, Stick corrected the depiction after Gerry noted it...(see his earlier post)


----------



## Herb Stoops (Aug 28, 2012)

Cherryville Chuck said:


> The bridle joint was the only type I remember seeing on the old counter-weighted sash windows. You remember the ones where every so often the cord attached to the weight would break and you'd hear the counterweight drop. Then it was a stick to keep the window open until someone got around to removing the molding and replacing the cord. It was common on door corners at the same time. It ws capable of with standing racking forces better than other joints.


I remember those, they were the standard then. A lot of times it involved removing plaster to fix, so they never got fixed. 
Herb


----------



## TWheels (May 26, 2006)

Cherryville Chuck said:


> Tage Frid's first book. It takes a little bit of reading to understand the format but it is a step by step account of how to make every common joint there is. For woodworkers this book should be considered a national treasure. https://www.amazon.ca/s?k=tage+frid+joinery+,+tools,+and+techniques&i=stripbooks&ref=nb_sb_noss I found my copy in really good used condition for a few bucks. They are often sold on ebay too and you may find it cheaper there.


Thanks very much @Cherryville Chuck. I have a copy ordered from Amazon.


----------



## Cherryville Chuck (Sep 28, 2010)

Tom after you've had a chance to go through it do a review. I think it's a great resource for anyone from novice to intermediate skills and since we always have around 2000 guests watching these days your review could be helpful to others.


----------



## DesertRatTom (Jul 3, 2012)

Best book I've found on joints is "The Joint Book," https://www.amazon.com/Joint-Book-C...keywords=The+Joint+Book&qid=1588610021&sr=8-1 $11 for the spiral bound version. Printed on heavy, plastic coated card stock. Spiral bound so it lays flat and meant to live in your shop. Clear illustrations and hints on best way to make any particular joint. Not sure a duscussion on such an ephemeral site as this will do the trick. I can't imagine doing serious woodworking without having a copy of this on hand, and at the price, an easy choice for anyone who wants to make stuff.


----------



## NorhS85 (May 13, 2020)

You are a good father  no solution her


----------

