How would I cut this wood perfectly straight?

[Chris142]

Wife wants a fence put up but it needs to be moveable plus I hate digging holes.

I'm no carpenter.

I put wood on the bottom but did not take into account that it's too tall if not partially buried. So I need to cut off about 12 inches of the bottom,maybe a little more.

I need to cut it straight so the poles don't lean all wrong and look trashy.

How do I go about marking it to cut straight?

 

[IndyIan]

10 or 12" Mitre saw. Gets most of the way through and flip it to finish. Make an extended table with some scraps. I have couple 12' 2x12's that I put on some saw horses and then screw down a "fence extender" at the end, line up the fence on the mitre saw with the extender, screw it down, add a stop block, and then I can cut up to 10' long boards all the same length exactly.

 

[Leo99]

Each post would need to be custom cut to account for the unevenness of your land.

 

[Rand]

you are in the middle of nowhere?
what is the purpose of the fence?

A 3ft high dog fence? otherwise I'm not sure how those are too tall.

 

[Chris142]

Each post would need to be custom cut to account for the unevenness of your land.

It will be on a cement slab

 

[Chris142]

you are in the middle of nowhere?
what is the purpose of the fence?

A 3ft high dog fence? otherwise I'm not sure how those are too tall.

It's to go around a picnic area..... She gets ideas.

 

[Tdbo]

She gets ideas.

Don't they all!

 

[Pew]

Not anywhere near a professional or amateur here but why not lop 12 of the top instead of the bottom? It looks like you already have them on a base and they look fairly straight at this angle.

 

[doitmyself]

It's to go around a picnic area..... She gets ideas.

Don't judge your spouse's choices...............she married you.

 

[doitmyself]

Not anywhere near a professional or amateur here but why not lop 12 of the top instead of the bottom? It looks like you already have them on a base and they look fairly straight at this angle.

Can't do that due to the hole placement for the cross members.

I cannot tell from the pictures if those have some taper - might make the miter saw solution a challenge.

If you are pleased with the current bottom squareness, I would measure up from the bottom in about 10 places, putting a mark at the 1 foot measurement. Connect the marks around the post. Use whatever saw of choice to stay on the line. Sawzall with 8 inch wood blade, chainsaw, hand saw. A similar idea: https://www.finehomebuilding.com/1998/07/01/marking-a-square-cut-on-a-round-column

Maybe cut a quarter of the way in, staying on the line, turn the post and cut another quarter way in, repeat all the way around. This helps to stay on the pencil line and not go crooked. The outside perimeter will be square. Depending on skill level, you might have to trim a bit off inside the circle a bit - wood rasp, chisel, sawzall, etc..

If not perfect, shim your "legs" as needed. Shims are the carpenter's solution to an imperfect world.

 

[tnt_motorsports]

FWIW, here is my method I would use.

Measure the width at the top of the post and divide by 2, let's call this "M1". This will give you the center of the post at the top. Identify how far from the bottom up you want to cut. Measure the width at this point and divide by 2, let's call this "M2". Take M1 and subtract M2, this will be the thickness of the "shim" required to hold the post square to the top. Cut the excess off with a hand saw or miter saw as you see fit.

 

[IndyIan]

Can't do that due to the hole placement for the cross members.

I cannot tell from the pictures if those have some taper - might make the miter saw solution a challenge.

If you are pleased with the current bottom squareness, I would measure up from the bottom in about 10 places, putting a mark at the 1 foot measurement. Connect the marks around the post. Use whatever saw of choice to stay on the line. Sawzall with 8 inch wood blade, chainsaw, hand saw. A similar idea: https://www.finehomebuilding.com/1998/07/01/marking-a-square-cut-on-a-round-column

Maybe cut a quarter of the way in, staying on the line, turn the post and cut another quarter way in, repeat all the way around. This helps to stay on the pencil line and not go crooked. The outside perimeter will be square. Depending on skill level, you might have to trim a bit off inside the circle a bit - wood rasp, chisel, sawzall, etc..

If not perfect, shim your "legs" as needed. Shims are the carpenter's solution to an imperfect world.

Good point with dealing with taper, but I would do the shimming on the mitre saw table to get the cut square and flat to the post centre line. Then he can just put in a large lag bolt from the bottom of the cross pieces into the post, and it will pull everything flat/plumb and strong.
Probably a good idea to predrill the hole for the lag bolt to avoid any chance of splitting.

 

[doitmyself]

I might be inclined to put together some permanent sections square and plumb, then insert the cross members between two or more of these permanent sections to make it longer. Deck screws are wonderful things.

 

[Chris142]

I might be inclined to put together some permanent sections square and plumb, then insert the cross members between two or more of these permanent sections to make it longer. Deck screws are wonderful things.
View attachment 276714

That's a great idea! Thx.

 

[Chris142]

Don't judge your spouse's choices...............she married you.

Not one of her better life decisions...

 

[zzyzzx]

She gets ideas.

Bad ones, apparently.

 

[spasm3]

I think this entire idea is bad. If anyone leans on it it will fall, someone could get hurt

A stacked fence would be safer, but would need to be a zig zag design.

 

[burbguy82]

It's to go around a picnic area..... She gets ideas.

 

[RhondaHonda]

Do you have a laser? Set them all on the concrete pad and mark your line using a laser level.

 

[Chris142]

Not anywhere near a professional or amateur here but why not lop 12 of the top instead of the bottom? It looks like you already have them on a base and they look fairly straight at this angle.

There are holes on the top for the other pieces to fit into