# Best way to attach hardwood edging to 3/4" ply?



## WalkerR (Feb 8, 2017)

I'm working on a mobile kitchen cart that has a plywood case with hardwood edging. I'll be adding a wing on folding shelf brackets. This wing will be 3/4" ply with 3/4"x3/4" mitered hardwood edging. What's the best way to attach this so that the miters don't separate, and the edging doesn't separate from the plywood?

Just glue? Splines in the miters? I just got a doweling jig. I don't have a biscuit jointer, but do have a slot cutter bit and can make biscuits.

I've simply glued hardwood edging to plywood cases before with success, albeit just using butt joints. However, on a previous project with a similar layout on a bigger scale, (the edging was 2" wide) I did tongue and groove all the way around, with mitered corners. The edging shrunk and the miters pulled apart, also some spots the edging pulled away from the center piece. Although, this was hardwood attached to hardwood.


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## therealSteveN (Oct 29, 2016)

Considering that for the most part the edge of plywood is edge grain. I like some form of interlock, so you are getting glue surface on face grain at least a little bit, that way you don't hear all your glue getting slurped into the end grain where it isn't going to do as much good for you.

The size is determined by the look you want, and also that the wider stuff stiffens the edge so you have less potential for sag.










But if all you are looking for is a way to hide the plies, glue on a solid piece, followed by some brads to hold it still have worked for a long time.


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## SMP (Aug 29, 2018)

I find that glue and brads/finish nails lasts longer than my wife likes the style or whatever and wants something else. Had a fish tank stand for 10 or 15 years that held up fine even getting splashed/leaked on with salt water.


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## WalkerR (Feb 8, 2017)

I need the edging to be the same thickness as the ply. The "Better" picture is what I've done in the past, but the hardwood shrunk and it pulled apart the miters. Anyway to avoid that? I can't store the wood in the environment it will eventually live in, because this will be a wedding present.


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## bandit571 (Jan 20, 2011)

Picture #4….


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## bilyo (May 20, 2015)

> I ve simply glued hardwood edging to plywood cases before with success, albeit just using butt joints. However, on a previous project with a similar layout on a bigger scale, (the edging was 2" wide) I did tongue and groove all the way around, with mitered corners. The edging shrunk and the miters pulled apart, also some spots the edging pulled away from the center piece. Although, this was hardwood attached to hardwood.
> 
> - Walker


This is not unusual when gluing hardwood edging onto the end grain of a hardwood panel. The hardwood panel will expand/contract across the grain and the long grain of the edging won't. Something has to give. That is what breadboard ends prevent. The "good" or "better" methods will work just fine on a plywood panel.


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## LesB (Dec 21, 2008)

One solution would be to make the end pieces thinner and just use but joints. Instead of 3/4" just make them 1/4" thick (by 1" wide). It is enough to cover the plywood and stand up to minor abuse but not thick enough for significant movement of the wood. If the plywood is sanded smooth the glue surface will be stronger than the wood…Tightbond III. I usually make mine slightly wider than the 3/4 ply (1") and sand or plane it down after the glue has set up. That way it is easier to glue and clamp and you know you have the plywood fully covered.


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## PPK (Mar 8, 2016)

> One solution would be to make the end pieces thinner and just use but joints. Instead of 3/4" just make them 1/4" thick (by 1" wide). It is enough to cover the plywood and stand up to minor abuse but not thick enough for significant movement of the wood. If the plywood is sanded smooth the glue surface will be stronger than the wood…Tightbond III. I usually make mine slightly wider than the 3/4 ply (1") and sand or plane it down after the glue has set up. That way it is easier to glue and clamp and you know you have the plywood fully covered.
> 
> - LesB


+1. Edging doesn't need fancy joinery. Butt joint is just fine for plywood. I use a flush trim router bit, and then sand. Never had edging come loose. Use TB III.


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## PPK (Mar 8, 2016)

One further thought. There's several things to consider when deciding what joint to use… Time, looks, strength. Lets face it. Plywood is going to de-laminate far before a butt glue joint fails. If it's not an aesthetic adder, then why use it? And try to beat the time of a butt joint… Those are all things that go through my mind anyway.

I guess on the other hand if you really enjoy the process, then go for that "fancy" joinery!


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## WalkerR (Feb 8, 2017)

The plan is to use the 3/4×3/4" edging to match the rest of the project. Ok, so butt joint is fine for the edging to plywood joint. Or T&G if I'm feeling fancy. My concern really is the mitered corners pulling apart. Do I use glue in the miters? Splines in the miters? Nothing in the miters?


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## PPK (Mar 8, 2016)

For a long time, I've used only glue on 3/4" edging with miters. Never had a problem with them opening up. You're using plywood, which doesn't have any significant movement, so you're fine with nothing. Again, a spline or other joint looks fancy, but not necessary in this case.


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## Bill_Steele (Aug 29, 2013)

If the edging is 3/4×3/4 there does not seem to be much room for reinforcement (e.g. a biscuit). I suppose a spline may add some reinforcement but probably not necessary. I would say just make sure you get plenty of glue on the end-grain of the miter joint and it should be fine.


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## ChefHDAN (Aug 7, 2010)

There are some nice bits to do this with your router table, take a look at these bits I have a larger 1/2" shank version that I will use when a straight glue up won't work. Do the two short sides and glue them in place, then use a backer block and cut the profile on the other sides all the way through he applied hardwood. It will lock it all together and give much more glue surface for your miters.


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## JackDuren (Oct 10, 2015)

> For a long time, I ve used only glue on 3/4" edging with miters. Never had a problem with them opening up. You re using plywood, which doesn t have any significant movement, so you re fine with nothing. Again, a spline or other joint looks fancy, but not necessary in this case.
> 
> - PPK


Agree. ......


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## Jimothy (Oct 29, 2015)

Yeah, I'm not surprised the miters came apart when it was hardwood to hardwood. The edging on the ends of the hardwood are cross grain and couldn't handle the movement of the middle/main section. With plywood though, considering the movement is very minimal, just using glue is fine. I've done it many times without problems! But yes, if you were to use hardwood on hardwood again I would definitely use miters, dowels or some other reinforcement on the miters.


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## Underdog (Oct 29, 2012)

> Yeah, I m not surprised the miters came apart when it was hardwood to hardwood. The edging on the ends of the hardwood are cross grain and couldn t handle the movement of the middle/main section. With plywood though, considering the movement is very minimal, just using glue is fine. I ve done it many times without problems! But yes, if you were to use hardwood on hardwood again I would definitely use miters, dowels or some other reinforcement on the miters.
> 
> - Jimothy


Actually on hardwood to hardwood you should accommodate the wood movement, and not use miters. You should make a sliding joint on the end grain. Otherwise you'll be disappointed every time, because the wood IS going to move… Especially on a piece of any size. For small boxes you might get away with it. But on a table size object? You're just asking for joint failure.


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## Redoak49 (Dec 15, 2012)

I just use glue on a butt joint. I clamp with blue masking tape and some times some brads to hold in place.


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## Bill_Steele (Aug 29, 2013)

I would say use a T&G approach to provide more glue area and make it self aligning-meaning apt to stay where needed during glue-up and clamping.

Definitely use glue on the miter. Consider glue sizing the miters with a watered down mixture of glue prior to final glue up. This will pre-fill the pores of the joint and reduce the potential for starvation due to absorption of glue.

Definitely consider using a biscuit, spline, dowel, or whatever you see fit to help reinforce the miter. This will provide additional support and maybe add visual appeal.

I don't know of a way to guarantee that the miters will not open up. Wood moves. The thicker and wider the wood-the more chance it will move enough to notice. If the wood needs to move and the glue joint holds strong, the wood will likely split somewhere else. There's a lot of force in the expansion/contraction. I understand ancient stone workers used wood wedges to split large stones-by wetting the wedges.


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## Foghorn (Jan 30, 2020)

These bits always looked interesting to me. Pretty pricey though. https://www.leevalley.com/en-ca/shop/tools/power-tool-accessories/router-bits/50698-plywood-edging-bits


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## pintodeluxe (Sep 12, 2010)

You should never "Picture Frame" hardwood. Ever. 
That's why you had problems in the past.
It's the classic Ana White blunder. Someone drew a pretty picture of a solid wood tabletop, with picture frame trim around the perimeter. Then they sold it as a plan. However, nobody in the process had the first clue about making furniture.

Trimming plywood with tongue and groove hardwood will work fine. I have used T&G or biscuits with equal success. If the sheet good piece is large, I use biscuits, because it would be too difficult to cut a tongue on a big piece of plywood.

Good luck with it.


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## Jimothy (Oct 29, 2015)

Ah yes, I actually mean't to write splines, not miters. But now that I think about it, you're right. 


> Yeah, I m not surprised the miters came apart when it was hardwood to hardwood. The edging on the ends of the hardwood are cross grain and couldn t handle the movement of the middle/main section. With plywood though, considering the movement is very minimal, just using glue is fine. I ve done it many times without problems! But yes, if you were to use hardwood on hardwood again I would definitely use miters, dowels or some other reinforcement on the miters.
> 
> - Jimothy
> 
> ...


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## bandit571 (Jan 20, 2011)

Hmmm..









Middle shelf. Ash edging glued to 3/4" Pine plywood…









Since the shelf wrapped around the legs….Didn't have to worry about the corners









Seemed to work just fine….


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