Message Thread:
Modular table
8/25/21
I have a client who is asking me to build a 12 foot table, single board top. Base will have 6 legs- four will go across the back incorporating a lower shelf in the middle and 2 in the corners on the front/back as per a regular table. There is a thin front rail that I plan to re inforce on the inside with angle iron or "u" channel steel to reduce any flex. The issue though is the client wants it to be modular to get it on his condo or apartment. I build with traditional mortise and tenon. The ends can be glued as well as the middle back legs. The rest need to be able to be broken down. Im thinking bed bolts for this. Ive done a few beds where I put the nut in the post or leg for this job and the route in a slot for the bolt on the inside of the rail. The bolt is tightened with a standard wrench. Anyone have any ideas besides the bed bolts? Im in the process of pricing/figuring it out now.
8/25/21 #2: Modular table ...
The two traditional solutions for this were worked out many years ago, before Ikea.
Dovetail tenons that slide into the posts from the top. A slight taper will make them go together well and be snug when driven home with a mallet.
Tusk tenons may work if you can offset tenons at the corners. We just did a large table with tusk tenons. While it took longer to make and get clean mortises, the ability to knock it all down was very appealing.
The photos below show the table. You can make out a few of the tusk tenons. By the way, this table is inches over 20' long, and it is 2-1/2" thick with no more support than usual. Wood is better at spanning gaps than you think. I'd forego the steel and just add another stretcher, back a bit from the front, and then you make it deeper since no one will ever see it at that angle.
View higher quality, full size image (4160 X 1920)
View higher quality, full size image (4160 X 1920)
8/25/21 #3: Modular table ...
Keep in mind no matter what knock down system you use, steel mechanical, tusked/wedged tenons, dovetails,.. on larger members they will loosen over time as wood comes and goes, wood fibers compress around the tensioning element. Its inevitable. Its why draw bolted (metal) furniture inevitably loosens over time, wedged elements (even a hammer head) loosen over time. The bigger the member the more/quicker.
Eliminating the wood from the connection all together in some way is the only option for a completely one and done solution.
8/26/21 #4: Modular table ...
All it takes is a tap on the wedge if the joint loosens.
8/27/21 #5: Modular table ...
No disagreement but the bulk of my customers dont want to have to do any tapping and they dont care for loosening up over time. Tons of ways to minimize it for sure but none the less a knock down situation if its expected to be dead tight in perpetuity its something to consider.
8/27/21 #6: Modular table ...
CBWW:
From your description, it sounds as though there will be some kind of top and bottom stretcher between the legs all around three perimeter sides.
I don't know what your legs will look like; if they are turnings like in David Sochar's photo, then this idea would not work. But if they are somewhat rectangular in section, you might consider splitting the legs in half lengthwise, mortise and tenon the top and bottom stretchers to the leg sections, and then connect the half section legs together with whatever method is workable and attractive to your design. You could make the seam on the legs a part of the design, if it is a contemporary looking table. Sort of like connecting sections of a fence. Bolt it all to the tabletop when connected.
There used to be forged steel bedhook hardware made in Germany that could be mortised into the faces of two mating pieces, those were quite strong and held up well over time. I think Highland Woodworking has some; see the link.
Curious about having the base needing to be a knock down design, but no concerns about getting a single board twelve foot tabletop into the condo.
Hope this helps, but probably just adds to the confusion.
TonyF
Bedrail Hooks
8/27/21 #7: Modular table ...
Metal fasteners will loosen up in time due to the movement of wood and the metal does not move. Even a nail can be worked loose in time.
Study your craft.
8/27/21 #8: Modular table ...
David Sochar:
Wooden knock-down joints will loosen up in time due to the movement of wood and the differences in wood expansion. Even a glued joint can be worked loose in time. Pick your poison.
I've studied my craft, and use the best method available for the particular situation and price point, even if it is not all wood.
Differences of opinion abound on this forum, that is the whole idea. No need to be arrogant.
TonyF
8/27/21 #9: Modular table ...
The legs are tapered, no stretchers, and paint grade. I priced it with reversed bed bolts and mortise and tenons(as usual).
Thanks for the responses.
8/27/21 #10: Modular table ...
Tony F
Since no one ever yields from their position of expertise, no matter how many years of experience anyone has, it's just the way the world and internet goes. Everyone is an expert and 100% of these experts never agree with anyone with a dissimilar opinion. No need to comment on anyone's attitude, it's universal. David and I have over 100 years or woodworking experience combined, we might just know what we are talking about.
8/27/21 #11: Modular table ...
David- The rails on your table- Its hard to see in the pic but guessing they are around 1 1/2" thick by 3" wide? Did you join those to the leg with twin dovetails or a tapered dovetail? Ive repaired a fair amount sliding dovetails that have failed.
The thru wedge tenons on the base- How do you avoid finish damage on install when you put the wedge in?
8/28/21 #12: Modular table ...
“Study your craft” is a phrase, a bit of really good advice from our moderator Gary Katz. I do not mean to imply that your craft was not informed. I asked that you expand your thinking to include wooden solutions. They were the First solutions in our craft. Metal solutions are sometimes considered quick and dirty by those of us with a historical perspective.
The upper rails each had a large dovetail fit in from above, driven in place at install. The lower tusk tenons went together like butter, and the tusks did not mar the surface. It was a “fast” angle, so it did not travel too far before tightening up.
8/28/21 #13: Modular table ...
A mechanical fastener, screw, lag, structural connection, does not work loose in wood. Through bolted, all thread, etc.. of course, wood on wood compression, its going to loosen.
I respect everyones experience and everyone has to make their own decisions but digging your heels in the sand for the sake of nostalgia and tradition is unfortunately more often than not a time tested recipe for an ever shrinking customer base. No one is saying make crap, no one is saying compromise your integrity, but the simple fact of the matter is if you were to build a door exactly as they were built in the middle ages you would have to be able to build them as a homeless person living under a bridge because you would have no customers.
I didnt build homes the same way I did 10 years ago (even though many builders mantra was "thats just the way weve always done it". We dont use finishes of old, weather sealing of old, thresholds of old, adhesives of old.. Things change. And while we all never want to cave on quality, the simple fact of the matter is there are innovations available now that simply never existed. They werent on the radar. And to arbitrarily "pooh pooh" them by default under the auspices of tradition is, in my opinion, bad business practice.
Heck, even the structural timber frame industry is starting to embrace manufacturing advancements https://timberframehq.com/shop/uv-t-concealed-hook-connector-timber-timber/
Its all down to the customers. If they are willing to have a table they have to tighten up occasionally and want traditional craftsmanship and will pay so be it. If the design criteria is otherwise, digging your heels in the sand is a perfect recipe for "we will keep looking". If thats fine with you... have at it.
8/29/21 #14: Modular table ...
Quality is a variable term. What is good quality to me may not measure up to you. Or it may be well above what another maker produces. My level of comfort may be different that yours. Not necessarily better, not worse, but different.
My customers may have variable definitions of quality, different from yours. And that is ok.
I look at this work historically. As a trajectory that originates centuries ago, and runs thru to today, and well out into the future. The use of materials and tools may change over time, but the woodworker must evaluate where he is on the spectrum at any moment. Is what we do day to day preserving, enhancing or disrespecting the craft? Do we care? Should we care?
I find it most comfortable when I know for sure that I am enhancing my craft. Everyday, I hope to enhance. Or at least, stay even.
Houses today are built quite differently from my 100+ yr old house. Better? Well, yes, there is a good deal of engineering behind the mechanicals than in my farmer plumbed and heated house. But the ‘better’ house has fake chimneys framed in wood, no masonry. And MDF trim. And MDF cabinets. No wasted materials. And this is better than plaster and lath, heartpine flooring, repairable windows, and native balloon framing? I know where I make my choice. You may choose elsewhere. And that is ok. It just is not what I choose.
Tradition? Is something better because it is traditional? Well, yes, the perception is that the older ways are better. This does not mean I work towards a completely medieval form of work, unless that is what I agree to with a customer. It does mean that traditional solutions are just that - solutions. Solutions that work, that are proven over time. MDF for cabinets - a terrible idea, and one that will soon pass. Replaced by something that will touted as quality sine it is replacing the cabinets that look terrible after just a few years service. And that replacement? Solid wood or future-goo goo - which is better?
Choose your path and follow it closely. Think about if you are enhancing or threatening the history of quality.
8/29/21 #15: Modular table ...
Website: http://cherrybrookwoodworks.com
With a public forum like this, you have no idea about the person asking the question. The skill set, work history, training etc..I probably should have posted my website link initially. All the ideas presented were all valid and appreciated. Thanks
8/30/21 #16: Modular table ...
Dont mean to be divergent to a modular table but but cross-trade speaks exactly to my point. Balloon framing, houses that burned in minutes, fell down, ridiculous quantities of wasted materials and resources, flawed reliance on fastener capacity, and the list goes on. Fire being the biggest single motivator. Entire cities burned to the ground uncontrollably due in large part to balloon framing even given the woeful capacity of bucket brigades. So what did we do? We advanced. Which is what we all do with finishes, fasteners, glues, adhesives, joinery, et al. We pick and choose. While your customer doesn't spec' the details of the entire process are unfortunately wrapped up in a gooey sticky bubble of a budget/profitability ratio. How you balance that out in your accounting software is up to you.
8/31/21 #17: Modular table ...
The problems associated with ballon framing were known - the wall cavities became chimneys in a fire. It was also known that the addition of a horizontal block could prevent the rapid spread of a fire. It was when people did not care/understand the importance of fire-stops that something like the Chicago Fire could happen.
But a new paradigm was sought and found in the development of Chicago Platform framing that more effectively slowed fires.
Of course, the real problem remained: the buildings were made of wood and wood will burn.
9/7/21 #18: Modular table ...
It wasnt just fire, it was sheer and utter waste of resources needing long members, precariously stood up multi story, interior platforms attached to vertical members with only fasteners, then later let-in when the shortcomings were obvious, the list goes on and on. It was a terrible building practice but held onto through decades because of "tradition" and "well.. thats just the way Ive always done it" coupled with a complete and utter resistance to change.
David, with all due respect, I have sat on my 150 acre piece of property and enjoyingly watched old timers that grew up cutting hay with a scythe, then a mule drawn sickle bar mower, then a tractor driven sickle, argue tooth_and_nail with "young whipper snappers" running disc mowers beside a 4wd tractor, and round bailers, that there were a million things wrong, cut the grass too short, didnt lay it over right, wouldnt windrow, left too much grass on the ground, over and over. Soon? That old man bought a disc mower, and a 4wd tractor to go with it, and was then tractor mowing places he use to cut by hand or leave because he couldnt cut it at all. Im a young man and Ive sat and witnessed these exchanges with my own eyes on my own property over and over and over as well as in business.
The smart whipper snapper (Ive not been all that effective) rolls all the past, into all of the now, and is always looking to all of the future, but doesnt drive a stake in the ground or dig his heels into any one of those three but weaves them all into forward momentum. Youve done the same. Your not using cut nails, slotted wood screws, hinges, latches, weatherstripping, finishes, etc.. Heck wood glue... caulking, IGU's? Where do you draw the line?
Balloon framing was wrong from the start. Its just what people did at the time. Shorter members, more efficient use of the tree, less reliance on fasteners they just didnt see platform framing out of tradition. Run down the list... being able to eliminate diagonal sheathing/wind bracing with ply sheathing (balked at), eliminating heat loss with window weight pockets (balked at),... all advancements that the old timers likely balked and balked but then slinked over and enjoyed the spoils.
Great to appreciate the old and honor the craft.
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