Board 1, Me 0

[Phil Mueller]

Ever have the slightily out of flat board and just can’t find what’s causing it to wiggle? One of the three boards I’m preparing for a panel (about 4’ long, 6” wide each), just won’t go flat. I’ve checked side to side down the length with a straight edge, end to end across the width with a straight edge, checked twist with winding sticks, knocked down a few high spots, replaned the whole thing, and the board still wins.

There’s a high spot or twist or something secretly living somewhere on that surface that I just haven’t found yet.

I’d question my straight edges, bench top, technique, etc., if it wasn’t for the fact the other two boards came out well using the same tools and process.

Walked away twice now. Maybe the third time is a charm.

Just had to share a moment of challenge in the world of woodworking.

[David Eisenhauer]

How does it mate up with one/both of the other two boards for the panel makeup? Does it look like it will edge glue OK? Assuming you are checking that potential makeup with the boards on edge, how does it look for edge gap(s) and general plane alignment of either one or both of the other boards?

[Pat Barry]

Ever have the slightily out of flat board and just can’t find what’s causing it to wiggle? One of the three boards I’m preparing for a panel (about 4’ long, 6” wide each), just won’t go flat. I’ve checked side to side down the length with a straight edge, end to end across the width with a straight edge, checked twist with winding sticks, knocked down a few high spots, replaned the whole thing, and the board still wins.

There’s a high spot or twist or something secretly living somewhere on that surface that I just haven’t found yet.

I’d question my straight edges, bench top, technique, etc., if it wasn’t for the fact the other two boards came out well using the same tools and process.

Walked away twice now. Maybe the third time is a charm.

Just had to share a moment of challenge in the world of woodworking.

Is the board flexing while you work it? Maybe need to shim under the high spots then plane the top surface flat, then flip it to plane the other side??

[Carl Baker]

String lines are always straight and you can't "flex" the board to them like you can to a bench or a straight edge. I would get an extra set of hands and start stringing end to end, corner to corner, etc.
Do you use winding sticks? String will get you by for now, but if you don't have winding sticks, I would highly recommend.

[Phil Mueller]

Thanks all for the suggestions and reminders. David, there are no gaps on the edges (those came out well). It’s just the face sticks up above the adjoining board face slightly in a spot or two...likely twist somewhere. I’ll get after it again this evening. Double check with the winding sticks. Pat, I appreciate the reminder of flex...one of those things I “know”, but forgot to consider. Certainly explains why I go to plane what seems to be a high spot, but can’t get a shaving...duh! And Carl, the string technique isn’t something I considered either...nice tip.

[Tom Trees]

You need a flat surface to plane on, that wont warp, deflect or move.
If you had a perfectly flat bench you could grasp the timber lightly from an end, and see if it turns like a propellor or pivots from the other end.
If it us touching in the middle and turning like a propellor, its high in the middle.
I have used methods like what machinists use for testing a flat surface, the prussian blue lapping technique, but with
dark crayons.
I cant seem to be able to post photos anymore, I have a piccy I'd like to show
When I select image, it wont let me search for it in the computer files, and also I cant use commas anymore
Real annoying

FIXED crummy google chrome was at fault
Tom
witness marks.JPG

[James Waldron]

How about checking for a "double twist"? Check from one end to the middle for twist; then check from the other end to the middle for twisting back to match the other end. It could happen. Maybe. If you're really un-lucky.

Great fun. Keep posting.

[Jim Koepke]

I cant seem to be able to post photos anymore, I have a piccy I'd like to show
When I select image, it wont let me search for it in the computer files, and also I cant use commas anymore
Real annoying

Did you change or update your operating system recently?

Your apostrophes are also a bit strange:

a.png

Is it possible you have "Smart Quotes" in use.

Just now looked for ' on Google. Surprisingly the answer came back:

b.png

This was returned even though &#39: was typed into the search string.

jtk

[Tom Trees]

Thanks Jim
Im gonna try and get the old firefox browser back if I can
Tomas

[Phil Mueller]

Thanks again, all. Ok, so it was rocking left top to right bottom corner. At most 1/16”, but I’m in no hurry and just couldn’t let it go. When rocking, the opposite corners weren’t touching the bench top...so something “inside” seemed to be the culprit. It also wasn’t rocking side to side (across the width), so figured it wasn’t just high down the middle. Put a straight edge back on and wiggled from end to end every inch of the width from both ends (thanks James!). Ahh...one high spot (I’ve now come to learn the culprit can often occur in a cathedral or “near knot” area..and this was the case. The level read flat when wiggling from the right, but pivoted on a high spot when wiggling from the left. But alas, when planning that area, no shavings. Yep, flex. Put a few playing cards underneath and off came the high spot.

That side is flat to my satisfaction. A wee bit of bow on the opposite side to deal with (where it needed the playing card shims). Don’t know if I’ll win, but I am gaining on it.

Trust me Carl, if the straight edge had not found it, the string was coming out.

All the suggestions are greatly appreciated!

[David Eisenhauer]

Good catch on the cathedral grain or near knot being a possible source of a high spot. Thanks for passing that along.