# Gluing plywood



## dfox52 (Oct 6, 2013)

It is a well known fact that gluing of end grain does not produce a strong joint. With that in mind, is the edge of 3/4 inch plywood considered end grain? When gluing nosing or an edge strip to plywood, is it advisable to strengthen the joint with nails or biscuits? Or will the glue alone make a strong enough joint? Thanks in advance for your input!


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## waho6o9 (May 6, 2011)

The "sizing" of end grain comes to mind;

Joint Sizing

Glue will soak more into the end grain of wood and can potentially result in starved glue joints. To help prevent this, you can "size" any end grain to be glued with a mixture of glue diluted with water. Dilute just so that when it is applied, glue drops don't form at the lower edges of the wood. Another method, somewhat less effective, is to coat the end grain with full-strength glue, allow it to dry 5 to 10 minutes, then re-coat with glue and assemble.

From: http://www.renovateyourworld.com/HowTo_Library/Joint_Sizing--T259.html ^^


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## waho6o9 (May 6, 2011)

Depending on the application biscuits would look cleaner than nails and glue alone should be strong enough.


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## OCristo (Nov 15, 2016)

I do not like biscuit joint but it is one of the few cases *I think biscuit joints is very welcome: to join plywood*.

I have no dedicated tools for biscuits, I use my router with a channel bit and put biscuits side by side to make stronger the joint. It has worked for me.

All the best.


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## Redoak49 (Dec 15, 2012)

When I glue just a 1/4" or 1/2" strip to the plywood, I do not use anything but glue. I will use tape to hold it in place and a few brands. I never have had a failure with this.

If I am going to use a wider wood piece, I use tong and groove.


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## JBrow (Nov 18, 2015)

dfox52,

I think of the edge of plywood to be a hybrid of end grain and long grain would. The plys are glued to one another with the grain running perpendicular to one another in typical plywood. Therefore the long or short edges of plywood will offer some long grain that would bond well. The end grain plys will not bond quite as well. I have found that a simple but joint on ¾" plywood holds pretty well but stronger joints are available.

waho6o9's joints would do a good job of strengthening the edge banding or splicing. Biscuits are similar to the spline joint shown but offers less strength. Nails could also work but may not have the bite to hold well and nails leave blemishes that then may have to be addressed. When joining plywood perpendicular, my preference is a tongue formed on one edge that slips into a dado in the mating piece, similar to the second joint shown by waho6o9.


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## dfox52 (Oct 6, 2013)

JBrow, Yes… I started thinking about this after I posted the question. Plywood does alternate grain so it would have some amount of long grain for gluing. So unless there will be stress on the edge material, a glue bond should hold fine.


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## TheFridge (May 1, 2014)

I've tried it on a bench with success.


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## jerryminer (Jun 15, 2014)

I glue solid wood edging to 3/4 plywood all the time. Glue only. Works fine. Been doing it for 40 years, no failures


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## bondogaposis (Dec 18, 2011)

I glue solid wood edging to 3/4 plywood all the time.

Yah, me too. Never had a problem, the long grain ply's provide adequate adhesion to hold edging in my experience.


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## rwe2156 (May 7, 2014)

> It is a well known fact that gluing of end grain does not produce a strong joint. With that in mind, is the edge of 3/4 inch plywood considered end grain? When gluing nosing or an edge strip to plywood, is it advisable to strengthen the joint with nails or biscuits? Or will the glue alone make a strong enough joint? Thanks in advance for your input!
> 
> - dfox52


Actually depends on the # of layers. Every other layer will be endgrain.

For attaching edge strip, it depends on application. For shelves, I think you can get away with just glue. I like to make a rabbet in the bullnose to catch part of the surface of the ply.

If there will be stress on the edge then I think you need more than glue. Many ways: splines, dowels, biscuits, pocket screws, screws and plugs, etc. .

and never had a failure.


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## a1Jim (Aug 9, 2008)

I agree with Jerry and Bondo an edge strip (banding) will be fine, if you want to take the extra step that's in the (better) photo of Wahoo's #2 post all the better but unless you have an unusual stress situation just glue and sizing the ply should work fine.


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## wormil (Nov 19, 2011)

> I glue solid wood edging to 3/4 plywood all the time.
> 
> Yah, me too. Never had a problem, the long grain ply s provide adequate adhesion to hold edging in my experience.
> 
> - bondogaposis


 +4

Glue is very strong. Once I made a refrigerator cabinet that we ended up not using so I decided to knock the joints apart. It was built with glue and pocket screws, after removing the screws I couldn't get the butt joints apart without splintering the plywood so I had to cut them.


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