Dinette Bench Plywood Thickness

[Scott]

On the maiden voyage with our new TT, I went to raise the dinette window blinds. I knelt on the bench seat and CRACK, the plywood failed. While I could stand to lose some weight, I'm not that heavy!

Upon removing the cushion, I found that the plywood is only 1/4" thick. I understand that they want to save weight, and the plywood is to be removable to get to the bench storage, but I didn't do anything I didn't do 100 times before in my popup.

So I'm going to have to replace it. But I have two questions:

1. What thickness plywood do I replace it with? 1/2", 5/8", 3/4", etc.
2. What type of plywood should I get? Sanded, hardwood, sheathing, etc.

I first did a search of the forum but that did not give me what I was looking for. Maybe I used the wrong search terms.

I understand the thicker I go the stronger it will be. But I don't want it to weigh a ton when I try to lift it up to access the storage underneath. So what's a good compromise? I'm thinking 1/2" sanded should be twice as strong as what was there but I don't know if that is the right call. Will that be strong enough if I kneel on it again?

Thanks everyone for your advice.

[freetime58]

Same thing happened to me last year. I replaced both with 3/8 sanded plywood. Used the old ones as a template................been good ever since!

[Scott]

Originally Posted by freetime58

Same thing happened to me last year. I replaced both with 3/8 sanded plywood. Used the old ones as a template................been good ever since!

Nice to know I'm in good company! Thanks.

[Randel J]

I agree with "freetime58", 3/8" sanded plywood is probably thick enough to prevent a reoccurrence. Although 1/2" plywood would practically guarantee your knee would never go through again. Anything thicker is unnecessary and too heavy. I've done the same thing and swore I wouldn't do it again, but as you can probably imagine, I've forgotten and almost broke the plywood with my knee again!

[Scott]

Originally Posted by Randel J

I agree with "freetime58", 3/8" sanded plywood is probably thick enough to prevent a reoccurrence. Although 1/2" plywood would practically guarantee your knee would never go through again. Anything thicker is unnecessary and too heavy. I've done the same thing and swore I wouldn't do it again, but as you can probably imagine, I've forgotten and almost broke the plywood with my knee again!

Thanks Randel. Those are my thoughts exactly. It’s not if I kneel on it again, but when.

[RetiredOne]

Originally Posted by freetime58

Same thing happened to me last year. I replaced both with 3/8 sanded plywood. Used the old ones as a template................been good ever since!

My rig came with 3/8, and I regularly kneel on it when moving the shades and so does wifey. So far no issues and no cracking.

[Tunce the traveler]

I think I went to 3/8” plywood with a hard wood facing. They sell them at Lowe’s in a 4x4 sheet. Put a poly finish on it and it looks much better than the original. NoW I did put a brace in the center for reinforcement.

[Rustynuts]

As a retired Cabinetmaker, I would suggest using a Baltic Birch plywood. It is much stronger than most plywood’s as it is made with more plys. A typical 1/2” plywood will have 3-5 plys where 1/2” Baltic Birch will have 7-9 plys. I would probably use 3/8” but definitely Baltic Birch, it also has a smooth sanded surface.

[Scott]

Thank you all for the advice. I'll post about the finished project. My benches came with a center support from the factory, so I don't need to add one, but it would be a good idea if one was not there.

[Scott]

I wanted to take a minute to follow up and thank everyone who helped me.

I bought some 1/2" sanded plywood and used the original as a template to trace the original on the new sheet. I then clamped down a straight edge to guide by saw to ensure a straight cut. I used a 1" spade bit to drill the finger hole after clamping a scrap piece of wood behind it to keep from blowing out the back side. I eased the edges with some sandpaper and the edges of the finger hole with the sanding bit on my Dremel. The replacements fit like a glove and a kneel tested and approved! Attached are pictures.