squaring up 4 x 8's bought at box stores

[lshah72414]

There was a topic a couple of days ago similar to this about 4 x 8's not square from the box stores. I can't find the link. Someone had just switched from a table saw to a track saw and he couldnot get the pieces square with his track saw.
Someone else suggested(picturing a rectangle, sides a and c are the long sides, b and d are the short) straightening one long edge with track saw, run a perpendicular line off the straight edge, and straighten b. Do the same with c and d. Then measure diagonally.
I did this and I was less than 1/16 of an inch off. My question is, for cabinetry, is being less than  1/16" off within the tolerances one can work with or should you be dead on? Thanks

 

[lwoirhaye]

For most work you're okay.  Cutting a full sheet with 1/16" of square is actually pretty good.  Squareness tolerances vary with different types of casework.  For frameless work precision is more important.

 

[tjbnwi]

1/16 total on the tape is really 1/32 each direction. Not to shabby.

Tom

 

[Jozsef Kozma]

I normally cut all sides so it is not an issue , because it gets corrected
On a 4 by 8 sheet as mentioned that is passable , but (1/16”)
on a 14” X15”piece that could be a major issue

I start with cleaning ( rip 1/16 of longway)
Then rip to exact with
Then cut to length ( square)

 

[ear3]

<1/16" on the diagonal of a 4x8 sheet is perfectly acceptable.

I work with a woodpeckers 26" precision framing square to do my sheets.  Cut the long side first using the 3000m rail, then line up a shorter rail on the framing square referenced off that first cut edge to do one short side.  All the other cuts flow naturally after making that one square angle.

 

[Stone Message]

There was a topic a couple of days ago similar to this about 4 x 8's not square from the box stores. I can't find the link. Someone had just switched from a table saw to a track saw and he couldnot get the pieces square with his track saw.
Someone else suggested(picturing a rectangle, sides a and c are the long sides, b and d are the short) straightening one long edge with track saw, run a perpendicular line off the straight edge, and straighten b. Do the same with c and d. Then measure diagonally.
I did this and I was less than 1/16 of an inch off. My question is, for cabinetry, is being less than  1/16" off within the tolerances one can work with or should you be dead on? Thanks

I normally run the saw along a long edge and create a tidy 8 foot long face edge. I then do a parallel cut, depending on the job, and end up with one piece with perfect parallel edges and the second with a new face edge.

After that I use my tracksaw cutting station (created with the Parf Guide System) to produce perfect 90 degree cuts.

My method is as cheap as chips and works every time.

You asked what accuracy you need for your work - the more accurate the better as everything fits together so well and life is so much easier.

Peter

 

[jacko9]

There was a topic a couple of days ago similar to this about 4 x 8's not square from the box stores. I can't find the link. Someone had just switched from a table saw to a track saw and he couldnot get the pieces square with his track saw.
Someone else suggested(picturing a rectangle, sides a and c are the long sides, b and d are the short) straightening one long edge with track saw, run a perpendicular line off the straight edge, and straighten b. Do the same with c and d. Then measure diagonally.
I did this and I was less than 1/16 of an inch off. My question is, for cabinetry, is being less than  1/16" off within the tolerances one can work with or should you be dead on? Thanks

I normally run the saw along a long edge and create a tidy 8 foot long face edge. I then do a parallel cut, depending on the job, and end up with one piece with perfect parallel edges and the second with a new face edge.

After that I use my tracksaw cutting station (created with the Parf Guide System) to produce perfect 90 degree cuts.

My method is as cheap as chips and works every time.

You asked what accuracy you need for your work - the more accurate the better as everything fits together so well and life is so much easier.

Peter

I agree with Peter but, I don't know how cheap chips are ;-)  Yes the more accurate your pieces the easier your assembly will be!

Jack