What is "AC fir plywood"?

[PC Gameplayer]

Happy holidays to all...

I was looking through American Woodworker #105 (Jan. issue) last night and I've pretty much decided to build their "Dream Bench". One stupid question has me stumped, though...

The plans specify 4 sheets of "AC fir plywood" and 1 sheet of birch plywood. The thing is, I don't know what AC fir plywood is. They unfortunately don't give the dimensions of the uncut sheets, but they do show a cut diagram. The fir plywood looks smaller than the birch ply sheet, but I don't know the dimensions...I just kind of assumed all plywood came in 48X96 sheets.

If they don't know what AC fir plywood is at Menards/HD/somewhere else, what should I be looking (or asking) for? Any ideas on the dimensions of said sheet of mystery ply? (C:

Thanks...

Jim

[George]

[Roy Smith]

In article ,

Softwood plywood comes graded A through D on each side, based on the number and severity of knots, splits, and other defects. Grade A is the best, and means no knots. Grade D is the worst. Each side is graded by itself, so AC mean grade A on one side, grade C on the other.

AC is a pretty common grade. Another common grade is "CDX", which is really ugly looking stuff used for sheathing in house construction (the X at the end means its made with waterproof glue for eXternal use).

You can find more details at

They unfortunately don't give the dimensions of the uncut sheets, but

Hmmmm. Don't know what to make of that. Plywood does come in other sizes, but 48 x 96 (commonly called "4 x 8", as in feet) is by far the most common size for both fir and birch plywood.

It's hard to imagine one of these places that didn't stock AC fir plywood in several thicknesses (3/4" being the most common). Just tell the guy, "I want 3/4 AC fir plywood". That's about as straight-forward as it gets.

[Upscale]

That leads me to ask. Do most/many wood dealers in the US stock actual 3/4" plywood or have you been inundated with metric sizes like we have been up here in Canada? 17 mm, 18 mm, 19 mm, 19.5 mm are all sizes I've come across. It's a pain in the butt and meant having to purchase a whole new group of router bits, rulers and having to be extra careful with calculations and measuring.

[Roy Smith]

You're right, it's not really 3/4". It's generally marked with some sort of whacko size like 23/32nds, which is a couple of smooches plus an RCH shy of 3/4". Does it work out to something exact in metric like

18mm? Maybe. Beats me.

[Lew Hodgett]

It depends.

If you are buying commercial products from yards that serve the construction industry, will be metric.

If you go to a plywood distributor who specializes in serving the cabinet and furniture market, they will typically have BOTH metric and US based on surface material.

HTH

[Plabovitz]

think it means one grade A side and one grade C side (one nice face) and the fir is probably a regional reference to the species used for the plywood..any A/C plywood should work fine....find a lumber grader at a sawmill and ask them for the specifics, maybe you wpould get a better and more accurate answer

Plywood is all 4X8 sheets standard with larger sizes uncommon but they exist

[nospam]

some other posters have answered the question of what fir plywood gradings and sizes are all about.

the birch ply may be birch veneer over a fir core- that stuff is also

4' x 8'. however, it may be the baltic birch ply, which has birch for it's internal plies and comes in 5' x 5' sheets.

Bridger

[B a r r y B u r k e J r .]

AC fir plywood is standard BORG variety ply, with on "A" graded face and one "C" graded face.

The only other piece of information you'll need is the thickness.

Barry