All bent out of shape: seeking square advice

[JPG]

My verification of alignment consists of using and observing the results.

If it ain't square, it becomes very obvious(assuming close inspection) and does not require measuring down to 0.001 resolution.

Now one must be choosey about how one uses it in order to be picky regarding the results.

If the workpiece drags on the blade as it moves past the back side the miter slot ain't parallel to the blade.

Ditto when ripping the fence is not parallel.

For miter gauge square, a single cut will reveal. If the just cut ends set on the table top do not yield parallel vertical edges, it ain't square.

The five cut is effective for sled "0" calibration, but not necessary for a miter gauge or adjustable sled.

For the bandsaw however, there is no blade backside to tell the tale.

[wa2crk]

Use the miter gauge and a small extension. Use a piece of scrap with a straight edge against the table and cut a small kerf in the stock. Mark the stock for right and left next to the kerf. Then rotate the stock to the rear of the blade with the kerf facing the front and now the R will be on the left and L on the right. The spine of the blade will slide into the kerf if the table is square to the blade. If not adjust the table as necessary and try again. You only have to move the adjustment by half of the distance of the difference.
Bill V

[reubenjames]

Got the bandsaw aligned tonight "good enough for government work.". I think it will be fine.

On to the more important work tomorrow of checking all my other alignments. I did a bit today, but need to go through the whole process.

I ended up buying a Starrett 12" combination square, and finding that my speed square wasn't as square as I had thought. I also tried the center punch trick on the carpenters square and, lo and behold, it worked! I'm still not sure how that wizardry works, so I'm reserving it for construction-level work, but it has been spared the scrap metal recycling pile for now. Machinists square and Starrett agree, dead on, as I expected.

[BuckeyeDennis]

It hasn't come up in this thread, so I thought this might be worth posting.

You don't actually need a "reference" square to check the accuracy of a square. All you need is one nice straight edge, and a pen, pencil, knife, or scribe.

Paul Sellars explains how to do it here.

The first part of Sellar's blog is about how to get a nice straight edge if you don't already have one. And he's actually incorrect that it only takes two edges to prove that both are straight .. it takes three to prove it conclusively.

But regardless, once you have a known straight edge, checking the square is super-easy.

[reubenjames]

Thanks. This is how I verified my Starrett. A good reminder though.

[JPG]

It hasn't come up in this thread, so I thought this might be worth posting.

You don't actually need a "reference" square to check the accuracy of a square. All you need is one nice straight edge, and a pen, pencil, knife, or scribe.

Paul Sellars explains how to do it here.

The first part of Sellar's blog is about how to get a nice straight edge if you don't already have one. And he's actually incorrect that it only takes two edges to prove that both are straight .. it takes three to prove it conclusively.

But regardless, once you have a known straight edge, checking the square is super-easy.

Three boards = A,B,C

A || B
A || C
B || C

All three must be true!!! || means parallel.

A key point to his two boards is the common stroke of the plane end to end.

[BuckeyeDennis]

It hasn't come up in this thread, so I thought this might be worth posting.

You don't actually need a "reference" square to check the accuracy of a square. All you need is one nice straight edge, and a pen, pencil, knife, or scribe.

Paul Sellars explains how to do it here.

The first part of Sellar's blog is about how to get a nice straight edge if you don't already have one. And he's actually incorrect that it only takes two edges to prove that both are straight .. it takes three to prove it conclusively.

But regardless, once you have a known straight edge, checking the square is super-easy.

Three boards = A,B,C

A || B
A || C
B || C

All three must be true!!! || means parallel.

A key point to his two boards is the common stroke of the plane end to end.

Yes, I missed that in Seller's blog ... I had only skimmed the planing part.

If both edges are planed together, it's impossible for one to be convex and the other concave. So prepared in that way, only two edges are necessary to prove the edges straight. I should have known better than to dispute Paul Sellers!

[lyall]

the easiest way the level a band saw table to the blade is one way I saw on youtube.
you can use a 4x4 or larger and make a short cut into the board. turn on the SS and turn the board over and see if the cut aligns up on the back of the blade. Keep adjusting the table until the cut matches. Then set the leveling screw and the auto-stop.

[dusty]

the easiest way the level a band saw table to the blade is one way I saw on youtube.
you can use a 4x4 or larger and make a short cut into the board. turn on the SS and turn the board over and see if the cut aligns up on the back of the blade. Keep adjusting the table until the cut matches. Then set the leveling screw and the auto-stop.

I think you mean 'turn off' the SS.

[lyall]

Yes dusty you are right

https://www.youtube.com/watch?v=DmtkafjkHuw

found this on youtube - Scroll saw blade alignment

it should also work for aligning the band saw