Glued up Bartop Slab Attachment... Help?

[Erich Weidner]

Hello,

I'm an amateur woodworker and small business owner (not related). I own a bar/coffee house and we are moving into a new bigger space.
In the new location, I've hired an experienced trim carpenter to build the bartop. It has a fairly deep overhang customer side (15"). Resultingly, for substrate, he has used a 1/4" steel plate topped with two layers of 3/4in plywood (seams overlapped). Plywood is screwed to the steel plate from below, and the two sheets of ply are glued and screwed together.

I've specified an edge glued up red oak slab countertop (He will be biscuting/dominoing them as well). He has built several bars and indicated he has always used troweled on glue to glue down the slab to the plywood and has never had a problem with separation or seasonal wood movement. However he normally builds it more like a floor and doens't edge glue he indicated.

Now, I'm an amateur, but I've read dozens of books and Fine Woodworking/etc. for the last decade of my woodworking hobby. Everything I think I know is that a glued up slab should NOT be screwed or glued to plywood. That with a table for example, we use some sort of attachment to the aprons that let the seasonal wood movement happen.

The big question: How should a glued up slab such as this (32" wide all said and done) be anchored to the plywood substrate? I'll take some pics when I'm at the jobsite later today. Being a $15,000 bar project, I want it to last for at least 10 years and not be pulling open at the seams or failing otherwise.

Any advice?

[Brian Holcombe]

That is not the right way to support a slab, it will have issues.

[Andrew Hughes]

You mention he builds it like a floor and doesn’t edge glue. What does that mean.
I have my ideas that could be the reason your carpenter isn’t worried about cupping or cracking.
Its always good practice to account for wood movement.
Good Luck

[Peter Christensen]

Here is a link to the Shrinkulator (http://www.woodbin.com/calcs/shrinkulator/). It will show you how much the slab could move over the plywood that won't. I don't think much of his proposed method, I'm an amateur too though. I would consult some other shops to see how they would propose doing it and what they would charge. Lowest bidder isn't always the best.

[Lee Schierer]

Your choice of wood could be better. Red Oak is open pored and you will have to work really hard t get it completely sealed so it won't suck in spills. White Oak, Maple, Walnut or Cherry would be better. You can actually blow bubbles in a glass of water through a short piece of red oak.

I wouldn't want a floor type construction on a table or bar. The wood will expand and contract seasonally and there will be gaps just like there is on a floor. Dirt and crud will get in them. I would insist on and 32" edge glued top and then allow for seasonal movement by anchoring the edge behind the bar so it can't move and then the screws up through the substrate should be in slotted holes so the wood can move. the fact that the over hang will move a little doesn't matter. Your customers will never notice it.

[Jim Becker]

I think I would bolt the slab directly to the steel plate from below with elongated holes across the grain to support seasonal wood movement. While I would certainly use Dominos/Dowels/splines/T&G during the slab assembly, I'd also edge glue it so it becomes a single surface, especially for this application. I agree about not using red oak...white oak is a better choice for moisture resistance if you want the look of oak.

[Phillip Mitchell]

Slotted / elongated holes from underneath is the proper way to attach something like this to allow for seasonal wood movement. You can go with one fixed point of non slotted screws, but all other areas should be slotted to allow the wood to move. It will move, no doubt. Maybe your trim carpenter has somehow never been called back about a glued down counter / bar top moving seasonally, buckling, or gapping but that's definitely not the right way to attach a wide, solid wood slab like this.

When you say floor construction, do you mean tongue and groove along the edges? As pointed out above, the wood will still move seasonally and gaps will open up at the edge seams in the drier months creating a nasty place for crumbs and detritus to gather in, which is a bit of a food safety hazard at a restaurant. It should be edge glued 100%, then the grain sealed, then some type of protective, film forming finish (waterlox, spar varnish, poly, epoxy, etc)

I also agree that there are many more appropriate choices than Red Oak. If you're spending $15k for the bar, you might as well make it something that's well suited for the application. White oak would be a better choice and most would say that it would be more aesthetically pleasing as well.

[Erich Weidner]

Thanks All,

Question on the slot: If a screw is tight with the steel plate at the bottom will it really be able to move in an elongated slot to allow for movement?

In answer to above, when I say built like a floor, I mean he was describing a sort of rebate/overlap with each board glued and nailed to the substrate.

As for finding another contractor, probably not enough time. My GC trusts this gentleman's work. I think I'm just going to insist on a method of attachment that will let me sleep at night RE: wood movement.

PS. I'll see if we can switch to white oak. I was wanting red because originally I wasn't planning on staining, and the slight pink of the red oak just looks better to my eye. Now I've got a bunch of stains to sample on scrap this week. I may well be going that route, so less concerned about white.

[johnny means]

I build a lot of butcherblock and slab type bars. We never use a substrate. Your 15" overhang should easily be self supporting. To be honest, your guy sounds like a hack. Flooring nailed to a substrate seems like DIY junk to me. For that type of money you should be getting a solid wood bar that should easily outlive your grandchildren.

[Erich Weidner]

I build a lot of butcherblock and slab type bars. We never use a substrate. Your 15" overhang should easily be self supporting. To be honest, your guy sounds like a hack. Flooring nailed to a substrate seems like DIY junk to me. For that type of money you should be getting a solid wood bar that should easily outlive your grandchildren.

The plan is to edge glue up a slab probably also with biscuits/dominos. I insisted on edge gluing. We have a 1/4" steel plate supporting most of the 15" overhang, and two 3/4" plywood glued together on top of that (seams overlapping). I thought it was overkill, but I've never built a bar and this is a pretty long run (~28' of the 15" overhang). At any rate it is already there. So forward I march.

The slab is to be built in place on top of the substrate. At this point I just want to focus on the attachment so we don't have problems in the future and staining/sealing/grain filling (I have another thread going in the finishing section on that).

[Jim Becker]

Question on the slot: If a screw is tight with the steel plate at the bottom will it really be able to move in an elongated slot to allow for movement?
The fasteners are tightened enough to hold things flat and a washer is used, too. Believe me, the lag bolt will move in the slot. A piece of oak like that can move an impressive amount seasonally. Doing it like a floor like you describe is asking for trouble, IMHO.

[Erich Weidner]

Using the Shrinkulator, given a 32" wide slab. I'm only seeing about 5/16" of tangential movement across the slab. Shouldn't need to do too much slotting then, if I'm reading that right.

[Jim Becker]

As long as the slots are longer than the maximum extend of movement and are placed such that they take into account a edge that might be constrained...such as by a wall or post, you'll be fine. Too long is better than too short... ;)

[Erich Weidner]

As long as the slots are longer than the maximum extend of movement and are placed such that they take into account a edge that might be constrained...such as by a wall or post, you'll be fine. Too long is better than too short... ;)

The screw holes in the steel plate were already drilled and countersunk. I may look to see if we can use an undersized flathead screw with a washer so as to allow for movement. But again, if it is screwed up tight will the wood movement really be able to drag the screw in the slot as it moves? Or will the screw be too friction tight to allow for movement?

[Jim Becker]

The screw doesn't need to be and shouldn't be "super tight" for this application. Snug so it holds things down, but not so tight that it totally constrains movement. You don't want the top to crack from that! 5/16" might seam like a small amount, but consider just how much stress/pressure that can create. Slots for movement are better since for that kind of weight AND application (a bar) you want to use fasteners that are strong. Downsizing to small screws might not be the best idea.

[Bill Space]

Just a couple questions/observations. Sorry if I missed the answers but I did look back...

How thick is the slap that will rest on the plywood/steel base?

Is there a chance the adhesive this guy is using would be flexible enough to accommodate the maximum wood dimensional change?

Slots to accommodate wood dimensional change will need to be in both the steel and the layers of plywood on top of it.

Not it sure I am adding anything but I am curious. 😀

[Erich Weidner]

I think the top will be built up from 1" thick boards. (Might end up 3/4" after milling/sanding).
Well, the guy claims the adhesive he uses has enough flex. But I've just never come across any book mentioning such a technique as valid.

Yes, the problem with slots is the steel plate. It is already installed and I can't exactly route a slot through it.

I have to admit dealing with this is stressing me out (and why I am up at 5AM on the forum). Might have been better if I was completely ignorant of wood working. Ignorance is bliss. At this point I just want to do what I can to ensure the top doesn't have problems in the future. Unlike with building tables, or chairs or book cases, I wasn't able to locate books on building a bar/bar top. (So many different DIY articles out there, none of which really I felt were solid).

I'll also admit, though researching and building this myself might have been a fun project, I don't have any prior experience with a giant slab, and I work full time in a different carrer than owning this business, so I just don't have time. Hence I let the GC hire someone he trusted.

At this point, I just want to step in enough to insist on whatever I still can to get a good result.
They carpenter warrants his work, but then people go out of business all the time.

[Erich Weidner]

OK, so now that I'm starting to second guess everything:
How should a corner of the bar be handled?

Meaning for the "L" / 90 degree turn at the end of the bar. Should this be a 45 degree miter of the two slabs? Or should it be "butted" together edge grain to end grain? I need to call today and see what the plan of record is.

Illustrations on this website: As usual my googling doesn't come up with anything I feel I can definitively point to as the "right way" to do it. And to attach it.
http://www.devoswoodworking.com/designing-wood-countertops/joints.html

I feel like, if it were me, I'd mitre and glue/domino it together. But as I said previously. I'm out of league here.

[Richard Coers]

I think the top will be built up from 1" thick boards. (Might end up 3/4" after milling/sanding).
Well, the guy claims the adhesive he uses has enough flex. But I've just never come across any book mentioning such a technique as valid.

Yes, the problem with slots is the steel plate. It is already installed and I can't exactly route a slot through it.

I have to admit dealing with this is stressing me out (and why I am up at 5AM on the forum). Might have been better if I was completely ignorant of wood working. Ignorance is bliss. At this point I just want to do what I can to ensure the top doesn't have problems in the future. Unlike with building tables, or chairs or book cases, I wasn't able to locate books on building a bar/bar top. (So many different DIY articles out there, none of which really I felt were solid).

I'll also admit, though researching and building this myself might have been a fun project, I don't have any prior experience with a giant slab, and I work full time in a different carrer than owning this business, so I just don't have time. Hence I let the GC hire someone he trusted.

At this point, I just want to step in enough to insist on whatever I still can to get a good result.
They carpenter warrants his work, but then people go out of business all the time.

Slots in steel can be cut in with a scroll saw with a metal blade, a rat tail file, or just a large round hole with a fender washer under the head of the screw. One of the basic issues you have here is most trim carpenters think they can also be furniture makers, I mean heck it's all just wood right? Norm Abrams went from a carpenter to furniture maker with just a few air nailers and a TV show after all!

[Brian Tymchak]

OK, so now that I'm starting to second guess everything:
How should a corner of the bar be handled?

Meaning for the "L" / 90 degree turn at the end of the bar. Should this be a 45 degree miter of the two slabs? Or should it be "butted" together edge grain to end grain? I need to call today and see what the plan of record is.

Illustrations on this website: As usual my googling doesn't come up with anything I feel I can definitively point to as the "right way" to do it. And to attach it.
http://www.devoswoodworking.com/designing-wood-countertops/joints.html

I feel like, if it were me, I'd mitre and glue/domino it together. But as I said previously. I'm out of league here.

I guess it's personal preference, but I can't imagine a bar top that is NOT mitered at the corners. As you mention I would definitely use a loose tenon of some sort (dominos, biscuits, spline, etc) in that joint.

Glad to hear that your carpenter warrants his work. there is no way I anchor a slab to plywood.

[Ron Citerone]

I sense you are not comfortable with this whole plan, and many here feel the same including me. I would get another quote from another contractor or two.

[J.R. Rutter]

Well, the guy claims the adhesive he uses has enough flex. But I've just never come across any book mentioning such a technique as valid.

Yes, the problem with slots is the steel plate. It is already installed and I can't exactly route a slot through it.


I've put down stair treads with silicone dots to allow some movement, but for a wide countertop like you are describing, I would stick with screws and washers through oversized holes.

For enlarging the holes after the fact, why not just drill through the steel and plywood with a larger diameter bit and use a bigger washer?

[Tim Bueler]

I sense you are not comfortable with this whole plan, and many here feel the same including me. I would get another quote from another contractor or two.

+1 on that!

[Erich Weidner]

I would stick with screws and washers through oversized holes. For enlarging the holes after the fact, why not just drill through the steel and plywood with a larger diameter bit and use a bigger washer?

I think that is an excellent suggestion (as are others above). Now I just have to insist he does it my way or fire him. (I don't like conflict, and already had a long conversation with him yesterday. He wouldn't budge from his opinion/method and frankly gave me several bits of data which are just plain wrong.) Sigh... I'm going to met with the GC in about an hour to discuss where to go from here with said carpenter. But I'm not going to be intimidated into accepting junk science from the "pro".

I frankly wish I had the confidence in my own wood working skills (and the time) to have just done this myself. Kind of feels like my garage full of tools have been betrayed by me hiring this out. :)

[Gary Ragatz]

Are you wedded to the edge-glued top? Seems like you could put a thick (say, 1/8") veneer on that substrate, add some edge-banding, and you'd have an attractive, solid bar top. Maybe the veneer doesn't even need to be that thick.

[Pat Barry]

The way I understand the top as being plywood I see no issue with using a flexible adhesive to attach it. There will be plenty of surface area to bo d it securely and permanently. Miter the top L section for best appearance.

[J.R. Rutter]

The way I understand the top as being plywood I see no issue with using a flexible adhesive to attach it. There will be plenty of surface area to bo d it securely and permanently. Miter the top L section for best appearance.

32" wide solid wood glued to plywood substrate is what the carpenter proposed.

[Brian Holcombe]

Long miters gap with seasonal change in relative humidity.

Im with Gary, a veneer with edge of your want would be much better given the bar. I did similar for a job that originally spec’d 3.5” solid slab top 53” wide. After discussing the limits of solid wood the clients agreed with my suggestion.

Solid wood is something I enjoy but it doesn’t work in every instance, I think it’s being used here outside of its best use.

Consider using a cabinet shop that specializes in veneer work for this kind of job. Considering the budget you should be getting something exceptional. You’re not far from Phillip Morley, he does very nice work and I do believe he works with shop sawn veneers.

[Malcolm McLeod]

Maybe a bit late to this party ...??... but on the matter of slotting the 1/4" plate and ply above it:

I'll assume you could/can/will use a 'fixed' row of holes on 'your' side of the bar top. Then to get a row of slotted holes on the patron's side, you could rent a (small) magnetic base drill press. It would probably take two people to position it on the steel from below, then drill 1-2 more holes adjacent to and properly aligned with any existing holes - - then use a grinder to smooth the edges into the desired slot shape.

It is possible you could get the mag-base drill to grab to the steel from the top. This makes positioning and operating MUCH easier, but I wouldn't count on it. Another option might be to borrow a 36"x24" piece of 1/2" plate, clamp it to the ply/steel substrate, then magnetically attach the drill from the top..?

And if push comes to shove, just use an offset grinder on edge thru the 1/4" steel, then match that slot with a mortice in the plywood, cut with a router.

Hope it helps, and good luck!

[Erich Weidner]

Well. I've parted ways amicably with the trim carpenter. However it now looks like I'm taking on the task of finishing the bartop.
There is already a plywood substrate. I don't want to start over, I just want to build a glued up slab on top of it.

Now, the question is... what is the best way to glue up said slab when it is longer than the length of a single board. That is, the longest section is about 20' long. If I'm using boards which are less than that.. do I stagger them? It is late, and I'm out of town until Friday so don't have access to my wood working books. Though I don't recall this coming up in them.

My coffee table was purchased and is glued up of finger jointed short pieces to create "long" boards. which are edge glued. That is not the look I'm going for. I'm fine if the boards are staggered, but should the ends of the boards be dominoed as well as the edge joints? (I know the dominoes/biscuits are strictly necessary for edge gluing. Not sure if I'm going to bother with that or not.)

Here is the current state of the bar w/substrate of metal and plywood.

409954409955409956409957

[Brian Holcombe]

Buy 20’ boards.

[Jim Becker]

While I agree with Brian that in the ideal world "really long boards" would be nice, they might not be all that available in the quality required and machining them might also be a challenge. If that is the case where you are, specific to your question, yes, if you need to extend length, I'd stagger the joints and personally, I'd use a Dominos, dowels or biscuits to help with alignment. You also need to absolutely be certain that the two boards being joined end-to-end are exactly the same width. Based on the photos, I see no issue to fastening your glued up surface to the existing substrate from the bottom with screws/bolts as previously discussed. You'll want to make the surfaces a hair wider than the substrate so that expansion across the grain will not cause a problem because you'll also likely want to have a thicker edge on the bar top to hide the substrate below it.

[Joe Chritz]

While I agree with Brian that in the ideal world "really long boards" would be nice, they might not be all that available in the quality required and machining them might also be a challenge. If that is the case where you are, specific to your question, yes, if you need to extend length, I'd stagger the joints and personally, I'd use a Dominos, dowels or biscuits to help with alignment. You also need to absolutely be certain that the two boards being joined end-to-end are exactly the same width. Based on the photos, I see no issue to fastening your glued up surface to the existing substrate from the bottom with screws/bolts as previously discussed. You'll want to make the surfaces a hair wider than the substrate so that expansion across the grain will not cause a problem because you'll also likely want to have a thicker edge on the bar top to hide the substrate below it.

This.

Only I would almost certainly build this in place. Secure a board from below, clamp the next one end to end with domino and clamp from below. You may have to make 2 really long bar clamps but pipe clamps are excellent at this. Temp screws can be used to hold everything solid until the boards are ready for finish. The next board in width gets clamped down and clamped to the long grain joint with traditional woodworking clamps. Wash rinse repeat. Either wax paper below and lift the bar periodically to remove or I would shellac the plywood and wax it really well before glue up and leave it. Any glue squeeze that hits ply from below should (great word isn't it?) not stick enough limit the boards.

For a 15K bartop I would drive and buy a Festool Rotex and dust extractor right meow. With that, good practice in milling and gluing and its a couple hours to prep for finish once everything is glued up and the final slotted attachments are in.

Also I am with a few others. Scrap the red oak and get something dense. Rift/1/4 sawn white with grain pore filler would be good and is a personal favorite. Maple would be another excellent choice.

P.S. I did this with an open stairwell top before I learned a few things and the end joints absolutely need something to hold them together on plane. Mine has separated on the surface because of little twists and the like. Now I would add a couple small dominoes and it would stay flat.

Do some research of commercial finishes. You will have to redo it often compared to a home bar. I would probably use Behlen's Rockhard and plan on a refinish every few years or so. Spray is my choice but that will be much more effort 3 years from now when the shop is in service. A brush on varnish should be able to be sanded smooth with sterated sandpaper and recoated. Advantage is you KNOW what the finish is so there is less guess work. Worst case is you do a complete mechanical stripping and refinish.

P.S.S. Honestly I hate hand finishing so much I would probably use Target Conversion varnish and mask and plastic everything next time.

Sounds like a cool project, cant wait to see it.

Joe

[Patrick Varley]

My amateur opinion would be to create boards of equal length using half lap or scarf joints. Then mill as one board for final glueup. That's from prior experience of trying to create a staggered glueup and having issues getting perfect end to end joinery. That could certainly just be deficiencies in my skill.

I'd anchor it to the substrates by routing slots in the plywood and attaching with washers as described elsewhere in this thread.

[Brian Holcombe]

Give these guys a call: https://www.horizonwood.com

Horizon are very reasonably priced for a premium product (super premium in my experience) and specialize in this kind of thing. I'd see if they have long lengths, or can make long lengths. Otherwise I'd want to see a unique way of joining two identical slabs. Don't need to deal with a local supplier, shipping is super easy for wood, you just pay money.

If you can't make the length, buy a boule (the entire log) so that you can flip two boards and match them end to end and join in a fashion which looks intentional.

IMO, I would move on from the idea of a glue up, you're making a huge amount of work for yourself and the finish product will be much worse for it if I'm being completely frank. Find someone local with big enough equipment. Flatten the slabs, sand the slabs, install the slabs, then finish sand the slabs and finish. If you intend to use a commercial finish, spray the bottom, install, finish top, spray the top in short order (not days, hours).

Don't finish yourself, bring in a professional that knows his stuff. Sand if you have the equipment, otherwise hire someone with the right equipment to do it for you.

If you can't find someone local, send them to someone such as Darcy Warner who flattens giant slabs regularly.

[mreza Salav]

What I propose might seem radically different but:

- I'd use 1/8"-3/16" (max) thick shop sawn boards and glue them (as veneer) to plywood
- Regarding the issue of length, I'd put all those veneers at 45 degree side by side, and that way you only need about 50" or so long boards.
- That would easily take care of that miter corner as the boards don't need to rotate, it just continues in the same 45 degree diretion.
- I'd cover the edges with a thick board as edge banding.

[Pat Barry]

What I propose might seem radically different but:

- I'd use 1/8"-3/16" (max) thick shop sawn boards and glue them (as veneer) to plywood
- Regarding the issue of length, I'd put all those veneers at 45 degree side by side, and that way you only need about 50" or so long boards.
- That would easily take care of that miter corner as the boards don't need to rotate, it just continues in the same 45 degree diretion.
- I'd cover the edges with a thick board as edge banding.

Great idea!

[mreza Salav]

Great idea!

Thanks. Forgot to add that it'll likely a lot less $$ and no back breaking job to handle super large boards (planing/joining/sanding etc).

[Ted Reischl]

I have nothing to add as to technique for construction.

But I do have a suggestion for dealing with the players. The sub contractor was hired by the GC. You hired the GC, your conversations should be with him not the sub. The reason for this is that the GC is the guy you pay, he understands that your unhappiness can cause him issues getting paid. The sub recognizes that you are not a professional and therefore feels that he can disregard what you think. He could care less about what a bunch of guys on some forum think or what you read in a magazine somewhere. If'n it were me I would ask the GC to show me some bars this guy built a few years ago to see how they have stood up. Sub contractors generally would rather poke their own eyes out than deal directly with the owner. Well, most of the ones I have known anyhow.

[johnny means]

What I propose might seem radically different but:

- I'd use 1/8"-3/16" (max) thick shop sawn boards and glue them (as veneer) to plywood
- Regarding the issue of length, I'd put all those veneers at 45 degree side by side, and that way you only need about 50" or so long boards.
- That would easily take care of that miter corner as the boards don't need to rotate, it just continues in the same 45 degree diretion.
- I'd cover the edges with a thick board as edge banding.
You'd be surprised how much force that veneer would exert on the plywood when it starts moving. Something's going to give, eventually. Most likely splitting of the veneer, all over.

[Pat Barry]

You'd be surprised how much force that veneer would exert on the plywood when it starts moving. Something's going to give, eventually. Most likely splitting of the veneer, all over.

Obviously for a bartop moisture is the biggest concern so it would need to be sealed very well. Doing that effectively will reduce the moisture caused expansion. The plywood is very stable as a base and when the veneers are laminated to the plywood the whole assembly should be very stable. It would seem this should work very well.

[mreza Salav]

You'd be surprised how much force that veneer would exert on the plywood when it starts moving. Something's going to give, eventually. Most likely splitting of the veneer, all over.

Isn't that how plywood is actually made? I've laminated 1/8" thick solid wood to plywood and it is still as solid as day 1, after years.
You need to have moisture control for sure and if that is maintained to a reasonable range I don't see why it wouldn't work.

[Erich Weidner]

I have a good source here in Austin for 3/4" 4S boards. (Which is what I was planning on using). Can get lengths up to 16 - 20 feet. But of course are not joint worthy straight. (Some crook typically).
I was planning to build on site (I can't handle long boards in my garage workshop and certainly can't transport the finished slab if I built it in my garage).

I'm not sure why a glued up slab would be a problem Brian? The top will have to be flattened in place of course. (Sanding and/or planing). Obviously, I'd need to get good edges for jointing. Might be time to break in my jack and jointer planes? :)

Assuming I'm moving forward with the glue-up in place... any thoughts on how to deal with the fact that I won't be able to use a single board that is long enough to span the whole distance?

Staggered looks better to my eye, but maybe not. (Two quick illustrations, not intended to be the whole bar, just an example of glue up options)

410141

[Brian Holcombe]

I like to work things in my favor, so I tend to plan my projects around that whenever possible, I do this because experience has taught me to do this. As example; I took on a large project requiring 16" wide quarter sawn solid wood panels, the only thing I could get locally was 3-4" wide quarter sawn boards. It took me on average 4-5 boards per panel. For the project that was quite a huge number of glue-ups. With a little more effort put in to finding a supplier I would have managed that in one glue up per panel, cutting the task down significantly and rather than do 3-4x the work for a lesser result.

So if I can buy material wide enough to make a single glue up, or no glue up at all, I do that. With every glue up comes the opportunity to have that glue up not align perfectly or not close at some spot and when it's 20' long with staggered lengths there much opportunity for disaster.

Long glue ups are not an easy task. If I want a glue up to go well I want to prep the stock from rough wood to finished product after it lands in my shop and acclimatizes for some time. I have the ability to face joint via machinery and then edge joint, straight line and thickness. If you are working with S4S then more trouble will certainly come your way.

Add a live edge and you have more trouble yet because the clamps can't grip the full thickness of the edge and will apply uneven pressure, so now you need to have a series of cauls made up for every joint.

This is how I would do this from ideal to less ideal:

Ideal: 20', full width slabs - Best result, requiring more work to prep but much much easier to install. No glue needed, easy living. Most certainly the best looking result at the end also.

Acceptable: 20' wide boards, 1-2 glue ups per. This will be more stressful than the above, but it's workable If you do something like tongue and groove or floating tenons to ensure that the glue up aligns properly.

Last Choice: Staggered short pre-prepped boards - requiring not only the sides to line up perfectly but the end butt joints as well. This is very impractical for someone without a shop that does this sort of glue up routinely. The end butts must be cut perfectly square and every part of the assembly much be cut tongue and groove to avoid misalignments. If you were my customer I would request you to chose from the above two options and I would refuse this last option.

Couple of notes

- Personally I like to apply pressure to a long glue up at about every foot (less if possible), so that would require 20-30 clamps in this case. I use bessey clamps, so that is $1200 in clamps required for this task.

- If you dont have a way to create floating tenons, then you can buy a domino, that adds another $1100 to the task.

So unless you want $2300 in equipment and a result that looks like a bowling lane in the best of cases, then consider adding money that to your material budget and get a good thing up front. Let people who have the machinery prep it for you, get a good slab, lag it down and move on to finish sanding and finishing.

[Erich Weidner]

Thanks Brian. I appreciate the advice.

FWIW, I do already possess a Festool Domino (I use it a lot. Love it!). I have only half the above number of Bessy and Jorgensen bar clamps. But I could probably borrow a few more and purchase the balance (can you really ever have too many clamps? :) )

I'm pretty comfortable with the idea of gluing up at the job site with Dominoes and clamps. This won't be the first slab glue up I've done, but certainly the longest!

I started out as a neanderthal and have slowly acquired supplemental power tools. I've always hand planed/jointed boards as I love using my planes. But I've never attempted to do a board so long as 20'.
I don't really have any desire to own an electric jointer (no space, and I just like using my planes, normally). Jointing is probably the thing I worry most about doing myself without taking forever. (That and how do I clamp it? My home shop workbench is too small). I'd have to rig something up at the job site... I had considered finding someone with a big jointer to assist in the board prep. I just don't personally know anyone locally).

Oh, and I have no issue with buying rough lumber and going from there either if that is a better way to approach vs 4S stock. (Same source in Austin carries rough cut material).
On that note: What about working from rough is superior in this application to purchasing 4s stock?

I'm going to go by Austin Fine Lumber later this week and see what width and length options I can source.

Cheers!

[Brian Holcombe]

I flattened a 48" wide by 72" long slab two-three weeks ago with hand planes (I'm the only professional in my area that does this as far as I'm aware). It was a 5 hour job. I

You'll have to joint by hand for the finished edges. What I would do is to buy rough lumber, have it machine jointed on one face and two edges. Hand plane, glue up into wide sections (16") have someone with a wide machine joint and plane those sections, then glue those two sections in place and hand plane the result.

OK, good luck.

[Erich Weidner]

Any reason not to do the above with 4S stock? (vs rough cut). Since the substrate and bar height were built assuming a 3/4" slab going on top, height is fine. (Another inch won't matter if it is taller). I'm just curious.

[Brian Holcombe]

I like some margin, so I don’t use S4S. It’s produced with a molder, so I don’t think it’s going to be perfectly straight over 20’. I’d rather have something jointed by hand fed machine and checked/paired with another board to ensure that the two edged match.

[Erich Weidner]

I've put down stair treads with silicone dots to allow some movement, but for a wide countertop like you are describing, I would stick with screws and washers through oversized holes.

For enlarging the holes after the fact, why not just drill through the steel and plywood with a larger diameter bit and use a bigger washer?

So, late reply.... but I tried this with my Milwalkee Heavy Duty corded drill and it just jerks my arms and binds up. Short of loading my drill press into my truck and taking to the job site, not sure what to do to widen the holes...

[Erich Weidner]

Well... two months later, and we are almost to deadlines with construction. I've stepped in to be the bar builder....

I already have the red oak for the bar. (too late, the guy I fired had already bought it, and it is what I originally speced).
The boards are S4S 1x6 red oak. I now need to flatten and square up for glue up. I built a bit of a work bench on top of the espresso bar... plan on attacking this tomorrow with my hand planes. (I don't own a power jointer).412229

[Erich Weidner]

Sorry for the rotated image. The software here doesn't auto-rotate stuff I guess. Unlike on my PC. :)

[Bill Space]

Not sure what size holes you are trying to make, but you might try a hole saw rather than a drill bit...hole saws can grab too, but I personally find them easier to handle for larger holes in steel.

[Don Stephan]

My understanding is that mitered corners open seasonally when surrounding a solid interior field. An L shape will not be surrounding a solid interior.

My understanding of solid wood flooring is that the individual boards (6" wide? 8" wide?) might be glued to the subfloor but not to each other, so individual boards can expand and contract in width seasonally but the annual movement over 6 or 8" is easily hidden by the chamfered edges.

Put down a temporary bar top, explain the situation to customers, and find a qualified person to make the permanent top without an impossible time constraint.

The concerns about red oak are confusing. Yes, the pores are open, but it's hard to imagine a permanent bar top that is not covered on all surfaces with a durable film finish. If enough moisture reaches the open wood pores to cause issues, it will have already caused damage to the film finish, won't it?

[Erich Weidner]

Well, we are now two years into using this bartop. I'll need to take some pics. The Red Oak has held up fine so far. It was finished with about 6 coats of GF Arm-R-Seal. I should probably clean it and add another two coats to keep it performing great.

Now, the back bartop which is under the taps has not fared terribly well. It was made of plywood, with same finish and coats. After constant exposure to moisture from drying glassware and the condensation dripping off of the draft tower, it was looking rough. I cleaned and dried it and applied an epoxy coat. But it looks like there must have been some places at the base of the draft towers for water to get under the epoxy. Not good. Now that I have some experience, for this back bar, if I had it to do again, I'd have done the epoxy on day one, and much thicker. At this point, I'd have to have the draft towers removed to redo the top. That is an expensive proposition, so I'm just going to have to let it go until it gets really bad.