I see this term 8/4 a lot when people talk about wood. Can someone explain it in plain English?

It’s a way to talk about the thickness of the board. 8/4 means it’s 2 inches thick. They measure wood in quarter inches. But once it’s surfaced, it’ll probably be around 1-3/4 inches.

Shannon said:

It’s a way to talk about the thickness of the board. 8/4 means it’s 2 inches thick. They measure wood in quarter inches. But once it’s surfaced, it’ll probably be around 1-3/4 inches.

Got it, so does that mean 4/4 is just 1 inch thick?

@Sam

Yep! And 5/4 would be 1-1/4 inch. But remember, it’s the nominal thickness. After planing, it’ll be a little thinner.

Shannon said:

@Sam

Yep! And 5/4 would be 1-1/4 inch. But remember, it’s the nominal thickness. After planing, it’ll be a little thinner.

I always hear people say ‘five quarter’ like it’s a thing!

Ali said:

@Indra

Haha, sounds like something Norm would say.

Totally, ‘Nahm’ vibes.

Memories… the flashbacks…

Ali said:

@Indra

Haha, sounds like something Norm would say.

Totally, ‘Nahm’ vibes.

“Normie, what do you say to a beer?”

“Daddy wuvs you.”

Shannon said:

@Sam

Yep! And 5/4 would be 1-1/4 inch. But remember, it’s the nominal thickness. After planing, it’ll be a little thinner.

Just to jump in here – ‘nominal’ means in name only. Like how a 2x4 isn’t really 2x4, but that’s what it’s called. Same with 8/4 – it’s close to 2 inches, but it’ll be surfaced down to a bit less.

Shannon said:

@Sam

Yep! And 5/4 would be 1-1/4 inch. But remember, it’s the nominal thickness. After planing, it’ll be a little thinner.

Americans and their measurements. Fascinating stuff.

@Griff

8/4 is about the size of an AA battery, or like two-thirds the height of a Big Mac if that helps.

Dale said:

@Griff

8/4 is about the size of an AA battery, or like two-thirds the height of a Big Mac if that helps.

Or 1/2160th the length of a football field.

Dale said:

@Griff

8/4 is about the size of an AA battery, or like two-thirds the height of a Big Mac if that helps.

Or 1/2160th the length of a football field.

Reminds me of that joke, ‘How many yards in a mile? No one knows.’ - Nate Bargatze

Remington said:

@Tan

George Washington definitely said that, right?

That guy was a great surveyor. No wonder he became president.

@Tan

Just divide everything by bananas. A yard is 5.143 bananas. A mile is like 9,090 bananas. Problem solved.