Need advice: Box does not sit flat on table (hand cut joints)

[Frederick Skelly]

Hi guys,
I hope you all had a good Labor Day weekend.

Im still practicing hand cut joinery by making box joints - 2" long rather than the usual small joints one would do with power tools. The joints fit pretty well (tight) and the inside corners glue up square. But the bottom does not sit level on my bench - one corner is raised about 1/8" off the bench. Looks like the box is slightly torqued even though its square in all 4 corners. All the corners meet correctly on the bottom - they are all flat individually - but one end is just torqued out of the horizontal plane. It was this way prior to applying glue and clamps, but I mistakenly thought that putting a weight on top while the glue was drying would solve that. (Nice try but no cigar, Mr. Skelly.) My camera is out of commision so I cant post a pic, but I hope you can visualize what has occurred without it.

All I can figure is that even though my joints fit tightly, one or more of the "tenons" (is that the right word?) was cut slightly canted (not parallel to the length of the bottom) and caused this effect.

Can anyone see where I went wrong?

Thanks in advance,
Fred

[Jim Koepke]

My recollection of who said, "box joints are just dovetails without the angles," is somewhat clouded. However like dovetails if everything isn't perfectly square during the layout, cutting, fitting and gluing they will be out of square after the gluing.

On a personal note, my dovetails have improved greatly since my paying more attention to making sure everything is square has improved.

My suggestion for your current situation would be to build a base for your box that compensates for the corner.

jtk

[Sean Hughto]

Do you own a table saw with a decent fence? If so, I think you can know where I am going ...

[Sean Hughto]

BTW, I made a box with hand cut joints this weekend too.

http://www.sawmillcreek.org/showthread.php?221309-Simple-pine-and-ply-box

The "trick" is to pay close attention when marking one board to the next. If you cut the grooves first, use a bit of the panel to match things up and then other boards to keep the ends and edges square as you mark.

[Stew Denton]

Hi Fred,

My solution would not be very high tech......but a sharp plane covers a multitude of sins.

Stew

[Pat Barry]

For the next one, clmaping the whole thing to a reference surface and then clamping the joints tight would be a good move. That will help prevent racking

[Jessica Pierce-LaRose]

Any time I've had something like this happen, it's simply been because the ends of my board weren't square, or the baselines of my joinery wasn't perpendicular to the bottom of the board. The larger the box gets, the larger the discrepancy becomes.

One way this can easily happen is if you square the ends of your boards referencing different long edges. Again, little differences accumulate.

If things aren't that bad, my solution would be like stew says, and plane it out. If things go together cockeyed, I haven't found that trying to force them square is incredibly effective.

[Don Slaughter]

Apparently the boxes were not were not cut square to the length. Impossible to guess without seeing the box but that would be my assumption from your description.
good luck

Don

[Frederick Skelly]

Thanks guys! Ill cut this one up and salvage the material, then try again, paying closer attention to the points you mention. All in the normal learning curve - frustrating, but it gets better each time.

Sean - nice box!

Have a good week!
Fred

[Jim Matthews]

Hi Fred,
My solution would not be very high tech......but a sharp plane covers a multitude of sins.
Stew

+1 on this.

Set your box on a known flat surface.
Use wedges, or folded sheets of paper to
get the top level to that known surface.

Hold a pencil flat to the reference surface
and scribe a line all the way around.

Plane to this line, or when the box stops rocking.

******

Alternately, use some spray adhesive to stick down some sandpaper
to cover an area larger than the box. Rub the box across this until
you have leveled the base.

******

If you've got tight joints, and a lid that fits - you're 80% finished.

[Mike Henderson]

I have several pieces of MDF, maybe 2 feet by 3 feet, that I've glued a large piece of sandpaper to - different grits on each one. I would take the box and place it bottom side against the sandpaper and just move it about. Unless the "outage" is really big, you'll sand the bottom flat.

Mike

[Tom Scott]

I've made quite a few boxes, and they seldom come out perfectly flat for whatever reason. A plane can quickly get it flat. I use a technique where you follow the sides all the way around using the previous side as a reference when you turn the corner. Harder toe describe than it is to do.

[Roy Lindberry]

Hi guys,
I hope you all had a good Labor Day weekend.

Im still practicing hand cut joinery by making box joints - 2" long rather than the usual small joints one would do with power tools. The joints fit pretty well (tight) and the inside corners glue up square. But the bottom does not sit level on my bench - one corner is raised about 1/8" off the bench. Looks like the box is slightly torqued even though its square in all 4 corners. All the corners meet correctly on the bottom - they are all flat individually - but one end is just torqued out of the horizontal plane. It was this way prior to applying glue and clamps, but I mistakenly thought that putting a weight on top while the glue was drying would solve that. (Nice try but no cigar, Mr. Skelly.) My camera is out of commision so I cant post a pic, but I hope you can visualize what has occurred without it.

All I can figure is that even though my joints fit tightly, one or more of the "tenons" (is that the right word?) was cut slightly canted (not parallel to the length of the bottom) and caused this effect.

Can anyone see where I went wrong?

Thanks in advance,
Fred


My thought is that perhaps one of the boards opposite the high corner has a bit of wind/twist. If the bottom of either of those is twisted inward, it could be causing your problem.

[Don Dorn]

You aren't the first and won't be the last. It happens to me once in a while too, and either you clamped a rack into it or there was a little twist in one or more boards. I'm sure it isn't too bad. I suggest setting it on a flat surface and holding it "level" and seeing which to ends and areas are high. Mark it with pencil and plane those areas down and try again. It won't take long and your box will set level.

[Jim Matthews]

http://www.hypersurf.com/~charlie2/DovetailDrawer/DovetailDrawer15.html

295953

[Sean Hughto]

Without a picture, I may be not understanding, but cutting it up and starting again seems pretty drastic. Just adjust the edges to make it sit flat. As noted, sandpaper, planes, or even tablesaws can make the slight adjustments.

BTW, similar adjustments are common in drawers and frame and panel doors. Warps can happen and need to be dealt with all the time. You can minimize the chances with certain practices, but they often creep in anyway.

[Jessica Pierce-LaRose]

My thought is that perhaps one of the boards opposite the high corner has a bit of wind/twist. If the bottom of either of those is twisted inward, it could be causing your problem.

This will certainly do it - I has what I thought was a flat board, and was surprised at how much just a little twist wonked out my drawer box.

[Prashun Patel]

I get the same problem. There are two causes: twist of individual boards or (more likely in my (in)experience) not cross-cutting the ends perfectly square to the long sides. BJ jigs usually reference off that end. So, the two ends will go together perfectly with no concern for how the sides line up. The bad thing is that the longer the side, the more the error is magnified.

[Frederick Skelly]

Thanks again guys. I appreciate the kind encouragement, pictures and advice. I think youre right - its also mportant to learn to correct my hand tool mistakes. So Ill try to correct it as you suggest.

As always, thank you!
Fred