Flattening a table top

[Bill Brush]

I'm still pretty much a woodworking newbie, at least when it comes to building furniture, but I'm working on a coffee table for my wife. I'm hoping it can be a Mother's day present.

So last weekend I glued up the top (24x45 rough dimensions). I had intended to take it to a cabinet shop for a trip through their wide belt sander to flatten it, but after last night I'm not so sure. See last night I thought I'll just knock down some of the ridges along the glue lines (edge glued, no biscuits or anything like that, so the edges weren't perfectly aligned along their whole length).

Fast forward a couple hours later and the top is almost entirely flat. The jack plane and the smoothing plane (and I) got a real workout. Any part of the workbench that wasn't covered by tabletop was covered in shavings about 1" deep.

Now I figure at this point I've taken care of the "easy stuff" getting it to about 85% flat. It's been kind of fun too. But to get the table top the last 15% is going to be the most challenging. So I'm looking for a reality check on whether I should continue or just take it in and get it sanded.

Tools I have:

#8C Stanley jointer plane (this hasn't been used on the top yet)
#5 Jack plane (Milers Falls)
#4 Smoother (Hercules)
Stanley block plane
Card scraper (I think I've finally got the hang of this one)
Palm sander (I would prefer to avoid power sanders because I don't have good dust collection for them)
Belt sander

The wood has some fun spots where the grain reverses and a few knots, just to make things interesting.

So realistically can I get the table top all the way to "flat" in a reasonable time frame with only the tools I have? I'm very impressed with what I accomplished last night, but I don't want to be foolishly optimistic.

[David Posey]

A table top doesn't have to be flat, it just has to look flat. It does need to look smooth. Keep this in mind and you may save yourself a great deal of work.

I'm a bit confused as to why you've used the smoother already, as the normal order of planes in this case would be jack then jointer then smoother, then the card scraper if you need to fix tearout. Do this and you shouldn't have to sand.

Does it look flat to your eye now? If so I wouldn't worry about anything other than smoothing out the rough spots. You may be able to do all of that with your No. 4 once you figure out where you need to change direction.

If it doesn't look flat, make a few passes with the jointer, first diagonally in both directions and then with the grain, and then use the smoother to fix tearout and remove any jointer tracks. Unless you have really wonky wood, you should be able to finish in about 20 minutes.

[Sam Murdoch]

Sounds like you are ready for a good scraper session. Most of the flattening was accomplished with your # 5 and # 4 smoother. Now if you want dead nuts - store bought type flat you might be better off to go find a wide belt. Stay away from using a hand held belt sander - way too much an element of risk tool. Another option is to break down and buy a Festool in line sander with their vac system :D.

HOWEVER - a table this size with so much of your heart and sweat into it is most worthy of a good hand scraping. This may leave the top a little "hand worked" but that is the lovely of it. Have fun.

Sam

[Charlie Stanford]

I'm still pretty much a woodworking newbie, at least when it comes to building furniture, but I'm working on a coffee table for my wife. I'm hoping it can be a Mother's day present.

So last weekend I glued up the top (24x45 rough dimensions). I had intended to take it to a cabinet shop for a trip through their wide belt sander to flatten it, but after last night I'm not so sure. See last night I thought I'll just knock down some of the ridges along the glue lines (edge glued, no biscuits or anything like that, so the edges weren't perfectly aligned along their whole length).

Fast forward a couple hours later and the top is almost entirely flat. The jack plane and the smoothing plane (and I) got a real workout. Any part of the workbench that wasn't covered by tabletop was covered in shavings about 1" deep.

Now I figure at this point I've taken care of the "easy stuff" getting it to about 85% flat. It's been kind of fun too. But to get the table top the last 15% is going to be the most challenging. So I'm looking for a reality check on whether I should continue or just take it in and get it sanded.

Tools I have:

#8C Stanley jointer plane (this hasn't been used on the top yet)
#5 Jack plane (Milers Falls)
#4 Smoother (Hercules)
Stanley block plane
Card scraper (I think I've finally got the hang of this one)
Palm sander (I would prefer to avoid power sanders because I don't have good dust collection for them)
Belt sander

The wood has some fun spots where the grain reverses and a few knots, just to make things interesting.

So realistically can I get the table top all the way to "flat" in a reasonable time frame with only the tools I have? I'm very impressed with what I accomplished last night, but I don't want to be foolishly optimistic.

If this hasn't already been said in previous replies: your plane inventory is more than adequate. What you need is a straightedge - bought or shop made in order to gauge flat. It's the most important tool to have for a task like this and I don't believe you mentioned having one.

Willy-Nilly planing without constant gauging (especially since you appear to be close to finished thickness for the top) is apt to produce disappointment if not rage.

Every plane pass you make at this point matters. You'd better be taking all of them in the right places.

Also, please note: the most important side to get geometrically flat (smooth is a surface attribute, flat is a geometrical attribute) is not the show side but the side which will register to the aprons. If you try to sock down a twisted top you'll pull the undercarriage into twist, drawers won't close properly (if it has drawers) and you'll have to trim at least one leg to make the table sit flat on a flat floor.

You also need to check that the undercarriage, sans top, has absolutely no twist. You need long winking sticks for this.

You need to lay an untwisted top onto an untwisted undercarriage for this project to be a success.

Sounds like you've figured out how to push a plane, unfortunately that's the easy part. Better check out the geometry of all the subassemblies before you remove another scintilla of wood. It's easy to get carried away making pretty shavings that appear to be coming off in the right places but that's not woodworking, or only an infinitesimally small part of it.

[Bill Brush]

A table top doesn't have to be flat, it just has to look flat. It does need to look smooth. Keep this in mind and you may save yourself a great deal of work.

I'm a bit confused as to why you've used the smoother already, as the normal order of planes in this case would be jack then jointer then smoother, then the card scraper if you need to fix tearout. Do this and you shouldn't have to sand.

Does it look flat to your eye now? If so I wouldn't worry about anything other than smoothing out the rough spots. You may be able to do all of that with your No. 4 once you figure out where you need to change direction.

If it doesn't look flat, make a few passes with the jointer, first diagonally in both directions and then with the grain, and then use the smoother to fix tearout and remove any jointer tracks. Unless you have really wonky wood, you should be able to finish in about 20 minutes.

Chalk your confusion up to me being a newbie with hand planes. The jointer is a wonking huge plane and it didn't seem appropriate for this job, so I didn't use it on the top (it did a dandy job getting the edges ready for glue.) When I started this I was just planning on getting it ready for the industrial sander, not actually flatten it. There is also the one knot almost perfectly in the center of the top which has already shown me that I need to respect it. My jointer plane is easily the best one I have, but I'm not sure who would win between the the two of them.

Anyway my forays into using the smoother (and the scraper) were more experiments into flattening than actually trying to flatten it.

[David Weaver]

Keep the belt sander on the rack. I don't know anything about a hercules, but it can probably be made to smooth anything.

Like charles says, it all counts. If it's not flat because you've worked an area over hard, when you put finish on it, it'll like the surface of a pond in a light breeze.

[Joe Bailey]

That Charlie Stanford post contains a great deal of wisdom.

[Bill Brush]

If this hasn't already been said in previous replies: your plane inventory is more than adequate. What you need is a straightedge - bought or shop made in order to gauge flat. It's the most important tool to have for a task like this and I don't believe you mentioned having one.

Willy-Nilly planing without constant gauging (especially since you appear to be close to finished thickness for the top) is apt to produce disappointment if not rage.

Every plane pass you make at this point matters. You'd better be taking all of them in the right places.

Also, please note: the most important side to get geometrically flat (smooth is a surface attribute, flat is a geometrical attribute) is not the show side but the side which will register to the aprons. If you try to sock down a twisted top you'll pull the undercarriage into twist, drawers won't close properly (if it has drawers) and you'll have to trim at least one leg to make the table sit flat on a flat floor.

You also need to check that the undercarriage, sans top, has absolutely no twist. You need long winking sticks for this.

You need to lay an untwisted top onto an untwisted undercarriage for this project to be a success.

Sounds like you've figured out how to push a plane, unfortunately that's the easy part. Better check out the geometry of all the subassemblies before you remove another scintilla of wood. It's easy to get carried away making pretty shavings that appear to be coming off in the right places but that's not woodworking, or only an infinitesimally small part of it.

Thanks Charlie.

I have done both sides to about the same level of planing, although I wouldn't put any money on the thickness being consistent. I have some aluminum stock I typically use as a straight edge, but maybe I'll pick up something a little more rigid. Or I might try the framing square.

The aprons and legs haven't even been touched yet (effectively). It's a good point though that trying to pull a twist straight with the aprons will put tension on the frame (which is bad). Would a cleat (batten) be the best way to flatten a twist that isn't feasible to plane out? I don't know if there is twist, I'm just asking. This wood is from a tree that was growing wild and a hobbyist milled it back in the early 70's, so it's not flat and uniform like you get from a specialty store. (Obviously I would need to allow for wood movement with a cleat.)

What's a reasonable tolerance for variance on a table? 1/16", 1/32", 1/64", .010, 001" "Whatever can be seen or felt"?

Thanks for the feedback guys. I suddenly realize I've only got 2 weeks to pull this off, so I can't afford to be learning by trial and error too much.

[Jeff Heath]

To add to what Charles, and others, have already stated, you need to take a step back away from the project and come up with a sequence of events that each should be completed before moving on to the next step.

Before gluing up your top, you should have thicknessed your boards. This means getting one side flat, and using a gauge to create a marking line all around the perimeter of each board to get them to uniform thickness. Then, joint an edge, rip to width, and joint all edges for glue-up.

Now that you already have your top glued up, you should be concentrating on FIRST getting one side flat. As Mr. Stanford already stated, planing away and creating shavings all over the place does nothing except get you a nice big pile of shavings, and a table top that is ever growing thinner. Get your winding sticks out, and get one side of the top flat. No need to smooth it yet, just get it dimensionally flat.

Now, using the flat side of your table as your reference, gauge a line of THICKNESS with your marking gauge as thick as you want the top to be, or as thick as your current glue-up will allow. Turn the table flat-side-down on your bench, and plane it to your gauge line.

You now will have a table top that is nice and flat, and also is of parallel thickness throughout. Without achieving a properly flattened and thicknessed top, you will have extreme difficulty getting aprons, legs, joinery, etc.....to work for you on the remainder of the project.

Get in the habit of "thicknessing" all your timbers for a project first. Depending on the stability of the stock I'm working with, I will do this 2 to 3 weeks ahead of starting a project. I will re-sticker all the freshly thicknessed boards in my shop, and let them re-acclimate and move again, if they will. Then, when I start building, I will, once again, re-thickness everything before moving on to glue-ups, joinery, etc.......

If your top is not thicknessed properly, you're never going to get the aprons to fit snugly to the bottom.

Jeff

PS Nice to see you 'round again, Chuckie.

[Jim Matthews]

If you don't have a dedicated straightedge that's long enough to span the width of your top, a new four foot level will be close.

Set up a single light, on one side of the table.
Set the straightedge between you, and the light.

Where you cannot see light coming under the straightedge, you have a high spot.
Mark those with pencil. The aim is to set the straightedge on your top, and have no light coming under.

It is possible to drive yourself over the bend with this process.

Your jointer is a good choice for flattening - I prefer to flatten tops with a plane around 10 inches long. A full size jointer is hard for me to handle with my arms at full reach.

Your real test is to put a wine glass on your top. You should be able to slide it across the width, without it rocking/catching/tipping over.

[Charlie Stanford]

Thanks Charlie.

I have done both sides to about the same level of planing, although I wouldn't put any money on the thickness being consistent. I have some aluminum stock I typically use as a straight edge, but maybe I'll pick up something a little more rigid. Or I might try the framing square.

The aprons and legs haven't even been touched yet (effectively). It's a good point though that trying to pull a twist straight with the aprons will put tension on the frame (which is bad). Would a cleat (batten) be the best way to flatten a twist that isn't feasible to plane out? I don't know if there is twist, I'm just asking. This wood is from a tree that was growing wild and a hobbyist milled it back in the early 70's, so it's not flat and uniform like you get from a specialty store. (Obviously I would need to allow for wood movement with a cleat.)

What's a reasonable tolerance for variance on a table? 1/16", 1/32", 1/64", .010, 001" "Whatever can be seen or felt"?

Thanks for the feedback guys. I suddenly realize I've only got 2 weeks to pull this off, so I can't afford to be learning by trial and error too much.

Forget the top for a moment, if the table base is made the first thing you need to do is check it for twist. This should have been sweated out during glue up. Maybe you got lucky. I hope you did. Let us know the verdict on the base. Don't put plane to top until you've assessed where you with flat and square on the base.

[Bill Brush]

Forget the top for a moment, if the table base is made the first thing you need to do is check it for twist. This should have been sweated out during glue up. Maybe you got lucky. I hope you did. Let us know the verdict on the base. Don't put plane to top until you've assessed where you with flat and square on the base.

I was actually planning on starting the base tonight, so that works out. I did check the top tonight and it appears to have a slight twist from one end to the other, something in the order of 1/4". I ran the calipers around the edge and everything is within 1/32" for thickness so I guess I did ok there.

At least with the next step there is almost no gluing to be done. :)

[Bill Brush]

I thought I'd take some pictures for posterity. Here's the patient with the motley collection of planes. (And a few shavings.)

231123231124

Here's a shot of my nemesis.

231125

This is the only bad knot I could not avoid. I haven't decided his fate yet. I might just fill it, or I might fill in around it.

[Jessica Pierce-LaRose]

I'd be tempted to put a dutchman there, but maybe that's just me. I like the look of 'em.

[Bill Brush]

Forget the top for a moment, if the table base is made the first thing you need to do is check it for twist. This should have been sweated out during glue up. Maybe you got lucky. I hope you did. Let us know the verdict on the base. Don't put plane to top until you've assessed where you with flat and square on the base.

I'm back, with a nearly complete table base. It's dry fit together, waiting on some smoothing with the scraper or sand paper before it gets glued up.

You can see it here. http://www.sawmillcreek.org/showthread.php?186175-Cofee-table-finally-started-WIP

So now sitting the top on the aprons it's got a noticeable gap on diagonally opposing corners. If I pull 3 corners tight it measures 3/16".

You can sort of see it here: 231617

I'm planning on planing the 2 corners that are currently in contact down so that the other 2 can touch. I'll be using my various and sundry straight edges to identify the target areas, but ultimately how it sits on the base is the key measure, right?