How to build a perfectly square wooden form

CurrentWave · May 21, 2013 8:48 am

Hello,

I cut 4 pieces of 1x4 wood - 2 pieces 10' and 2 pieces 10'1.5" to account for the 3/4" of the other 2 boards.

After assembling with the 10' pieces across from each other and the two longer pieces on the opposite sides overhanging the 10' pieces I measured the diagonals - and guess what they are off by 2". So I remeasured and my boards are the sizes I planned for.

So how does one cut boards and assemble to make a perfect 10' square? Or any square for that matter....

Thank you, from a distressed clueless newbie

Mike8136 · May 21, 2013 6:50 pm

Easy. No saw cut will be square enough to assemble square over 10'. Your form needs to be levelled and staked into position before concrete is placed. Stake one side, push the frame until the diagonals are the same and put the other stakes into the ground.

bashworth · May 21, 2013 6:58 pm

You always need to adjust the angles based on checking the diagonals,
or
Set up a simple right angle as follows
Measure 4' from the corner along one piece of wood.
Measure 3' from the corner along the other piece of wood
Adjust the wood until the two marks are 5' apart and the angle will be 90 degrees

CurrentWave · May 22, 2013 2:24 am

Okay, so if I'm hearing right my cuts were ok but my square wood form is a bit tweaked, and I should be able to push it right.

I'll give it a try ~ Thank you

JohnLou · Jun 14, 2013 8:24 pm

As bashworth says 3,4,5 triangle with 5 being the diagonal