Cherry plywood table top?

[gerti]

I will be renovating my home office, and in the progress get frames for height adjustable tables. Due to the somewhat odd dimensions I need I'll have to build the tabletops myself.

I have my heart set on Cherry, but due to time, space and shop restrictions a solid glue up is sadly out of the question (maybe later). So I am thinking of picture-framing cherry plywood with 1 2/2 x 1 1/2 solid cherry (or whatever dimension I can find) so I can build it up a bit and machine a generous round-over onto the edge. Most work has to be done in-place (speak in the house).

Amateur questions (sorry, there are many):

- Is that going to work, or will the solid border expand and contract too much over time and kill the joins? Longest solid edge will be 60".

- Can I get away just butting the edge onto the ply with glue, or am I better off cutting a rabbit into the edging for more glue surface? Do I use biscuits (I'd prefer not so there is no danger of exposing them when applying the round-over)?

- Because parts will be permanently covered, I can't let it light-age. So I am thinking of using a gel stain to bring out the cherry tones right away. Any recommendations?

- I plan on using gel PU finish, because It'll maintain a bit of the wood texture, dries quick and is dead-easy to work with. Or am I better off using wipe-on?

- It would safe a lot of time if I would not need to finish the underside. Bad idea because of the way humidity will affect top and bottom different, or not a big deal because it is plywood?

Sorry, I know those are many questions... But I'd appreciate any tips. Will have to work at those desks for many years (unless I decide to replace the surfaces eventually), so I'd prefer not to hate them! The last ones ("just temporary until we have time and money to look for something better") ended up being in use for 20+ years!

Thanks

Gerd

[JR]

- Is that going to work, or will the solid border expand and contract too much over time and kill the joins? Longest solid edge will be 60".

This will not be problem at all.

- Can I get away just butting the edge onto the ply with glue, or am I better off cutting a rabbit into the edging for more glue surface? Do I use biscuits (I'd prefer not so there is no danger of exposing them when applying the round-over)?

You'll want to do something to beef up this joint. The plywood edge will act like end grain, making it difficult for the glue to hold. You could think about shaping the edge before assembly in order to mitigate any risk of exposing the joint when you round it over. Feeling around under my store-bought desk I see they added an extra layer of plywood underneath the top layer, offering more surface for the edging - the edging appears to have been nailed in place. This second layer is about 4" wide and also includes 1" versions where the tabletop rests on the drawer boxes. Think of it a sort of lattice work under the table top.

- Because parts will be permanently covered, I can't let it light-age. So I am thinking of using a gel stain to bring out the cherry tones right away. Any recommendations?

Hey, whatever floats your boat!

- I plan on using gel PU finish, because It'll maintain a bit of the wood texture, dries quick and is dead-easy to work with. Or am I better off using wipe-on?

Once again, if you like it, go for it.

- It would safe a lot of time if I would not need to finish the underside. Bad idea because of the way humidity will affect top and bottom different, or not a big deal because it is plywood?

You'll want to finish the underside, especially if the tabletop is going to float free. If it's screwed into the base in a lot of locations there would be less risk. It doesn't have to be pretty and you could do it before final assembly. You might even think of it as a place to test the stain to see if you like it.

HTH

[gerti]

Good idea using the bottom for stain testing, thanks!

[poolhound]

I have used this General Finishes stain for cherry and like how it looks. I used it for the built-in below that was solid cherry but it should look just the same with a ply.

- Because parts will be permanently covered, I can't let it light-age. So I am thinking of using a gel stain to bring out the cherry tones right away. Any recommendations?

[Cochese]

I built both the kitchen table and the sideboard in that manner, and I have had no issues. The sideboard made use of the Domino, but I used a T&G joint for the kitchen table. Our house can see some wild humidity swings, but no apparent issues right now.

[atgcpaul]

Are you all happy with the durability of a plywood top, though? I have never found plywood to hold up to dents and dings like solid stock.

[Ken Weaver]

Where do you get your cherry ply?

[capncarl]

Some like the gel stain, obviously because it is still on the market, but the only thing I can say for it is I was glad to be able to salvage the project and get that gooey mess off my wood. Liquid stains for me from now on.
capncarl

[Cochese]

Are you all happy with the durability of a plywood top, though? I have never found plywood to hold up to dents and dings like solid stock.

The relative cheapness of it lets me swap it out in a few years or so if needed. Depends on how heavily the surface is used and abused. No real dings or anything in our kitchen table, just shoddy construction on my part.

[poolhound]

Agreed, I have never really seen the benefit of the gel stains. Possibly of minor help with minimizing runs on vertical surfaces but you can still make plenty of mess with gels if you don't take care what you are doing.

Some like the gel stain, obviously because it is still on the market, but the only thing I can say for it is I was glad to be able to salvage the project and get that gooey mess off my wood. Liquid stains for me from now on.
capncarl

[JR]

It's my understanding that gel stain is more of a coating than a stain that embeds itself in the fibers of wood. This is viewed by finishing professionals as an advantage because it minimizes the difference in the rate of "set" between the plywood surface and the solid wood.

Which reminds me: use sanding sealer before staining.

[Ken Massingale]

Where do you get your cherry ply?

Tidewater in Greenville has it, also The Lumber Yard in Mauldin has had it in the past.

[JimD]

I would use biscuits. Even the largest, #20, are less than an inch wide. They thus only go into the wood 1/2 inch (on each side). With 1 1/2 inch edging you should be well away from the biscuit with the roundover. Biscuits will add some glueing area but will also align the solid wood edging with the plywood. You need to be VERY careful sanding the plywood to flush up this joint - so aligning it at glueup is important. The risk is sanding through the veneer. You could also use a spline.

The type of the wood used in the inner plys of the plywood will help to determine its durability. The softer they are, the more easily damaged the top will be. If you can find plywood with birch inner plys, it will be better. Poplar I would rate better than softwood.

[gerti]

Which reminds me: use sanding sealer before staining.

Even on cherry? I know it's advised for pine, didn't know I'd need it for cherry though. Would a thin coat of shellac work?

[JR]

Even on cherry?

Yep. I made an alder table using similar construction to what you are planning. There is a noticeable difference between the solid wood and the plywood. The local finishing expert uses sanding sealer on every project. He says it provides a base that results in a more consistent finish.

Yes, shellac can be used as a sealer. I haven't done it, so I don't have specific advice. It will obviously cast a yellow tint to the work. Although shellac sets up quickly I 'd wonder if you have to let it "cure" before top coating.