Technique for getting legs to be level?

[Anna]

Hi, everyone,

I need some advice and insight for a little problem I encountered. The answer is probably obvious, but I can't really see it right now.

I'm building my first bench, and it's been quite a learning experience so far. I'm using a very simple design with 4x4 legs and top and bottom spreaders all around using 2x6 and 2x4 Douglas fir. The top spreaders, made of 2x4's, are flush with the top ends of the legs.

The problem is that after glue up, my bench legs are not perfectly flat on the floor. Two legs that are diagonal to each other are "longer" than the other two, so the thing wobbles. They did start out to be exactly the same length, which means that some of the legs are probably not plumb.

I thought I should use the belt sander to trim the legs down a little bit, but when I turn it over, the table top is not level either. So it's kind of hard to find a good reference point.

My husband suggests trial and error - that is, shave the legs off a little bit, turn it over to check, turn it over again to shave off, and so on. This is a VERY heavy base, and I don't really like the idea of having to wrestle with this thing multiple times. Besides, I have a feeling that it'll probably make things worse.

What I think I should do is try to level out the top first by either shaving it or putting on a flat top (like plywood) and shimming it. Then turn it over, and use that as a reference. But that sounds pretty complicated. So the question is: Is there a simple way to do this?

Thanks for any help,
Anna

[Thom2]

one of the ways that I recall, don't know if it'll work for this application tho', is to get the legs on a flat surface shim one of them to keep it from wobbling. Take a pencil and lay it flat on the surface and scribe a line all the way around each leg. Saw off at the line on each leg ... this should get it REALLY close.

option # 2 that I recall .... screw in leg levelers

I'm sure other ideas will show up shortly

[Anna]

Thanks for the idea, Thom

I actually started by measuring how much the "short legs" are short by, and tried to transfer that to the "long legs," but that didn't seem to come out right. I like the idea of just cutting a bit off all the legs, though (I didn't think of that at all). I already trimmed it by 1/4" from the originally planned length because I was trying to get them all to the same length. I guess another 1/4" or so shouldn't be too bad. I'll just use an extra 1/2" sheet of plywood on the tabletop. So, unless someone else comes up with a better suggestion, I'll get on it tomorrow.

I'm refusing to use levelers (for now) since, as a learning woodworker, I should be able to come up with a way to get my projects leveled out "properly." Of course, as a last resort....

[LCHIEN]

Thanks for the idea, Thom

I actually started by measuring how much the "short legs" are short by, and tried to transfer that to the "long legs," but that didn't seem to come out right. I like the idea of just cutting a bit off all the legs, though (I didn't think of that at all). I already trimmed it by 1/4" from the originally planned length because I was trying to get them all to the same length. I guess another 1/4" or so shouldn't be too bad. I'll just use an extra 1/2" sheet of plywood on the tabletop. So, unless someone else comes up with a better suggestion, I'll get on it tomorrow.

I'm refusing to use levelers (for now) since, as a learning woodworker, I should be able to come up with a way to get my projects leveled out "properly." Of course, as a last resort....

The first problem is, is the floor level? Almost never will you find a perfectly level floor in a home or residence. It'll be off a noticable amount. You don't notice on carpet but on hard floors/concrete floors/tile you do and that's why even perfectly level tables have leveler feet on them.

The second problem is making the legs the same length, this is accomplished with a crosscut saw or table saw with stops so that you cut each to the same length, regardless of what the actual length is. I.e. if you wanted 30" legs, if you actually cut 30-1/4" it would not really be a big deal if they were all the same length. So use stops or at least lay one on top of the other to make the the same length.

The final problem is, you have to have a square reference to build you r table. When you build the apron or stretchers they all need to be in the same plane, not looking like a kite. To do this you have to build it on a flat surface, like a good workbench. That of course is hard to do when you're building said bench.

If you set all the legs on the floor and build it you will liekly make it uneven/twisted because the floor is not flat. The solution is to build a flat top and put the legs below, or
build it from the ground up and attache the stretchers at a specific height, like 12". Then lay a level across it and shim each leg until that end it level, then move the level to the other end and do the same. Then swicth the level 90 degrees and do the sme to both ends the other way. Use only one screw at this point.
If the stretchers are in the same plane and the legs are the same length then the top will be in the same plane too. Then and only then glue it and use multiple screws.

hate to say it but trimming legs after it's built is for cartoons.

[Anna]

I initially cut the legs using my CMS. I don't have a miter saw station, so I can't use stops to make sure the legs are exactly the same length. I then came up with the bright idea of using the SMT on the BT3100 on the right side of the blade and used the fence, also on the right side of the blade, to set the length. I trimmed the four legs in turn, while I moved the fence a bit at a time. That's how I got them really close to having the exact length.

You're right about not having a bench to build a bench. What I did was I laid a 3/4" plywood sheet on the floor and used that as my assembly "table." I should have built the sawhorses first, but I wasn't smart enough to realize that I really need those. Anyway, I did the assembly on top of the plywood on the floor. I didn't check for level, but everything was supposed to have been referenced to the plywood.

I had problems with the glue up, though. I glued the short sides together first using biscuits. They were pretty tight, and I had to use a mallet to get them together. I didn't think that was right. After thinking about it, I realized that the 4x4's, which are Douglas fir, probably expanded/swelled up since it's been days since I initially cut the biscuit slots. I was being deliberate and didn't want to hurry things up. Serves me right.

Anyway, I figured this out after gluing up the short sides, so that probably contributed to the problem. I re-cut the slots for the remaining sides, and the biscuits were okay. But damage has been done.

It's my first time to put together something like this, and I didn't exactly have someone to instruct me while I'm doing it. It's definitely a learning experience. Don't even get me started on how I went about figuring out drilling for 3/8" lag bolts through the 4x4 and into the stretchers (which bits, how to drill for countersink, how you can't use a spade bit AFTER you've already drilled the smaller hole first...).

Anyway, I don't mind trimming the legs even after it's all put together. At worst, I can always use levelers.

Now, to accomplish this, do I use a planer, a belt sander, or a hand saw?

The first problem is, is the floor level? Almost never will you find a perfectly level floor in a home or residence. It'll be off a noticable amount. You don't notice on carpet but on hard floors/concrete floors/tile you do and that's why even perfectly level tables have leveler feet on them.

The second problem is making the legs the same length, this is accomplished with a crosscut saw or table saw with stops so that you cut each to the same length, regardless of what the actual length is. I.e. if you wanted 30" legs, if you actually cut 30-1/4" it would not really be a big deal if they were all the same length. So use stops or at least lay one on top of the other to make the the same length.

The final problem is, you have to have a square reference to build you r table. When you build the apron or stretchers they all need to be in the same plane, not looking like a kite. To do this you have to build it on a flat surface, like a good workbench. That of course is hard to do when you're building said bench.

If you set all the legs on the floor and build it you will liekly make it uneven/twisted because the floor is not flat. The solution is to build a flat top and put the legs below, or
build it from the ground up and attache the stretchers at a specific height, like 12". Then lay a level across it and shim each leg until that end it level, then move the level to the other end and do the same. Then swicth the level 90 degrees and do the sme to both ends the other way. Use only one screw at this point.
If the stretchers are in the same plane and the legs are the same length then the top will be in the same plane too. Then and only then glue it and use multiple screws.

hate to say it but trimming legs after it's built is for cartoons.

[Stytooner]

I actually designed a built a leg leveling table in a furniure factory I helped setup once. It was basically a torsion box table top covered with plastic laminate. There was a cutout in the right rear corner that contained a motor with a 7 1/4" blade mounted on it so that the blade was in the same plane as the table. Of course it had a blade guard and no it wasn't polycarbonate. The longest leg was trimmed by the blade to be flush with the other three. Some chairs need no cutting, some needed one leg cut and a few needed 2 legs cut to get the chairs to sit good on the table.
The furniture being leveled was cheap 2 by pine dining chairs. Formal dining sets in Alabama.
Even though all the parts were basically identical and the chairs were screwed together on jigs, they still had to be leveled. There isn't anything wrong with having to cut off a leg after the project is bult. Especially so when the legs are square. As with the chairs, its part of the production and perfectly acceptable as a solution.
Where it's not as desireable is when the legs are turned. Even these get leveled in a factory setting, but as a hobbiest, I would want to take the time to get these just right.
They way I do things like this is to use cauls on a good workbench. If the bench has a true flat surface, chances are your project will be flat too.

[Tom Miller]

Good advice so far, but the question you need to answer for yourself before proceeding is:

Is the surface that the tabletop will sit on (stretchers/leg tops) in-plane now?

If not, then shortening legs will only make matters worse.

There's a good chance that the legs that seem too long at the bottom, are going to seem too short at the top.

One way to check this is to pull a string from the top of one leg, across to the top of the diagonally opposite leg. Then, pull a second string across the tops of the two other diagonally opposed legs. Do the strings just touch in the middle?

Regards,
Tom

[Anna]

Hmm. Good idea. I only checked the top for level, and it's certainly not. I didn't think about it in terms of being "in plane."

(5 minutes later....)

I just checked it. They're off by 3/32", which is exactly what the "short" legs are off by!

Edit: I forgot to ask: So how do I fix this?

Good advice so far, but the question you need to answer for yourself before proceeding is:

Is the surface that the tabletop will sit on (stretchers/leg tops) in-plane now?

If not, then shortening legs will only make matters worse.

There's a good chance that the legs that seem too long at the bottom, are going to seem too short at the top.

One way to check this is to pull a string from the top of one leg, across to the top of the diagonally opposite leg. Then, pull a second string across the tops of the two other diagonally opposed legs. Do the strings just touch in the middle?

Regards,
Tom

[Anna]

Hi, Lee!

I tried looking it up, but... what are cauls?

I'm in the interesting quandary of needing a nice, flat, level bench to build a nice, flat, level bench. It did make me feel better when you said that this happens pretty commonly. I was really disgusted with myself yesterday when the problem became evident and started referring to the bench as "that stupid bench."

Being new to all this, I tend to gravitate towards the more complicated solutions. Right now, I'm leaning towards using a router-planing setup to level the top (after shimming and leveling the legs), then turn it over and use the same thing to level the bottom. I'm just hoping that an easier, more effective solution shows itself before I start building the jig.

I actually designed a built a leg leveling table in a furniure factory I helped setup once. It was basically a torsion box table top covered with plastic laminate. There was a cutout in the right rear corner that contained a motor with a 7 1/4" blade mounted on it so that the blade was in the same plane as the table. Of course it had a blade guard and no it wasn't polycarbonate. The longest leg was trimmed by the blade to be flush with the other three. Some chairs need no cutting, some needed one leg cut and a few needed 2 legs cut to get the chairs to sit good on the table.
The furniture being leveled was cheap 2 by pine dining chairs. Formal dining sets in Alabama.
Even though all the parts were basically identical and the chairs were screwed together on jigs, they still had to be leveled. There isn't anything wrong with having to cut off a leg after the project is bult. Especially so when the legs are square. As with the chairs, its part of the production and perfectly acceptable as a solution.
Where it's not as desireable is when the legs are turned. Even these get leveled in a factory setting, but as a hobbiest, I would want to take the time to get these just right.
They way I do things like this is to use cauls on a good workbench. If the bench has a true flat surface, chances are your project will be flat too.

[Tom Miller]

Hmm. Good idea. I only checked the top for level, and it's certainly not. I didn't think about it in terms of being "in plane."

(5 minutes later....)

I just checked it. They're off by 3/32", which is exactly what the "short" legs are off by!

Edit: I forgot to ask: So how do I fix this?

First, you should determine if it needs fixing. The point being that with a little weight on top, the high legs may very well just settle into place. So, have hubby sit on one high leg (if we men can't be used for our intelligence, we can at least be used as dead weight ), and you push down on the other one. How much push does it take to straighten? How does that compare to how the table will be loaded?

BTW, what's the intended tabletop material?

Regards,
Tom

[onedash]

Do you have supports underneath? I built a bench and the legs were not actually legs but a wide board with and arch cut on the bottom of each to give it 4 feet?? Anyhow once it was done and you sat in the middle it bowed. So I took a couple strips about 1 1/2 wide and screwed and glued them underneath like a joist and it is Very stiff now. The same thing might work to straighten the top out. As long as you are using some square stock and its sturdy enough when you attach it underneath like braces it should pull it flat...

[DaveStL]

Years ago I built my first bench w/ a 2x4 frame. It was for the basement, so it needed levelling legs. I drilled holes up through the bottom for hex bolts (I think 3/4" dia holes for 5/8" dia bolts), with a concentric, slightly larger diameter hole just deep enough to recess a nut-- the diameter was equal to the flat-to-flat dimension of the nut. Then I used chisels to make the recesses tightly fit the hex pattern, and tapped in the nuts. Installed each bolt with another nut on the shaft, and a rubber furniture leg tip on the head so it wouldn't skid.

I leveled the bench to the floor, and cinched the nuts that were loose on the shaft up to the recessed nuts to lock the levellers in place. It was cheap, easy, and I've never had a problem with it. The bench is very solid.

[Anna]

I'm attaching a picture of the part I've put together so far. It's very solid. I doubt my husband (who weighs less than 160 lbs) and I (who weigh less than 110 lbs) would be able to twist this thing into shape just by sitting on it.

It's totally overengineered, I think. There are two rows of biscuits on each leg - making that 2 biscuits for the 2x4's and 4 biscuits each side for the 2x6's. Then I hit on the bright idea of using lag bolts to make it REALLY solid, for a total of 16 3/8" lag bolts on the legs so far. Of course the problem is that now, I can't twist or re-adjust the darned thing if my life depends on it.

The options are reduced to these two, as far as I can figure it: 1. Use levelers like Dave and Thom suggested, and 2. Do some shaving on both top and bottom. If I use levelers, then I'll have to use shims on top to make sure the bench top is level.

The bench top is going to be laminated MDF - 2 sheets of 3/4" MDF glued together - plus a 1/2" birch plywood on top to make it easy to replace. I wanted a butcher block top, but I figured I can always replace the top later.

[RodKirby]

Hi Anna,

Lookin' good so far. How does this sound (it's how I built mine):

"Find" a flat area to lay the top face down, upend the base and attach it to the top, drill and insert a 3/8" (dia. bolt) leveller in each leg. (With a friend), turn it the right way up. Level it.

I have a concrete floor that's anything but level. My bench and all my floor standing "cabinets" (DP router tables etc), all use levellers.

Not as well built as yours, but it is flat and LEVEL:

[mschrank]

I think levelers are perfectly acceptable and maybe even desireable for this application. Don't think of it as cheating.

As mentioned, your floor is probably not perfectly level. Even if you get the legs trimmed/sanded to prevent the rocking, you might decide to move the workbench to a different spot someday (I've change the position of mine 3 times in the past year), and you'll have to start all over again because the floor will be different in the new place.

Also, if you decide to trim the "long" legs, you might find that after enough tweaking, your bench will end up being only 1' tall!