Seeking your ideas for: A) Slab desk and B) Small Night Table

[smorgasbord]

First stab at a base design.

So, I just finished building a prototype out of scrap wood (mostly pine I think).

It works and hold the weight just fine. Bridle joints are pretty cool.

However, the table isn't stable horizontally at the single leg end. I can try to get some video, but what's going on is that the bottom stretcher is being twisted by forces when you push away on the table to roll your chair back from it. It's not going to fall or break or anything, but it's a bit disconcerting and unacceptable. Even with the top not on, I can move the top of the angled leg horizontally and see the bottom stretcher twist.

Of course, now my question is whether making this out of solid cherry instead of slapped together pine (which is pretty badly laminated I have to admit) will improve things enough. I'm suspecting not.

There could be many fixes, here are some off the top of my head:
1) Convert the angled leg into a wider leg assembly. It doesn't have to be near as wide as the main slab leg, maybe 8" would do.
2) Attach a foot the the end of the bottom stretcher (or near where it attaches to the lef), perpendicular to it. The idea is that the foot width will prevent that part of the stretcher from twisting since doing so would have to lift the whole table. This would be the same effect as #1, but using less wood.

This would be very similar to:


Except instead of the angled leg at the end, this one has a vertical leg near the slab leg.
3) I could just have two legs at the end away from the slab leg, and even lose the bottom stretcher. But, that's a whole different design aesthetic.
4) I could put a drawer stack at the far end. Again, not he aesthetic I'm looking for, even if more practical.

Anyway, just talking out out here. Thanks for listening.

 

[rvieceli]

@smorgasbord is the prototype top securely fastened to the base? I'm thinking that when the base and the top are actually fastened together, it should be difficult for the end of that top and the leg supporting it to move at all. Eliminating the horizontal movement on the end.

Ron

 

[smorgasbord]

is the prototype top securely fastened to the base?

That was my first thought, too. And no, it's not firmly attached since it's just a prototype. But, it's definitely not sliding, so I didn't pursue that.

Maybe the slab leg is able to twist a bit, too? But, now that you mention it, I could trying using double stick tape or maybe some short screws up into the top to see if that improves things. Thanks!

 

[smorgasbord]

Showed my wife the mock-up base with the real top the other day.
Her first comment is that the top is too thick (it's 48mm). She pointed out that our actual Nakashima furniture have tops that are an inch thick. As I originally thought as well.

The problems are that taking it down to 1" risks potato chipping and instability at the knot holes and such. I'd probably patch with butterflies on top before taking the bottom down (up?). I'd have to take it to a place to do this as I don't really want to buy/build a router sled thing for this 42" x 60" slab.

So, I'm thinking:
• Install butterflies as desired/needed.
• Get it thinned from the bottom to about 35mm-40mm thick
• Under bevel the edges to make it look thinner

First two are straightforward enough. Ideas for the under-beveling? I don't own a power plane - yet.

 

[luvmytoolz]

First two are straightforward enough. Ideas for the under-beveling? I don't own a power plane - yet.

You could make a simple jig like the attached pic I found for the router with a long 2 flute straight cutter (or dovetail) to achieve a bevelled edge.

 

[luvmytoolz]

Or even use a smaller vee bit with a template that you move inwards as the cutter moves up, so you get a clean sweeping angle that looks like it was cut in one pass.

 

[smorgasbord]

You could make a simple jig like the attached pic I found for the router with a long 2 flute straight cutter (or dovetail) to achieve a bevelled edge.

I don't want to mess with the edge, which is the "live natural edge," I want to bevel the underside. If the table were square, it'd look like this:

 

[luvmytoolz]

I don't want to mess with the edge, which is the "live natural edge," I want to bevel the underside. If the table were square, it'd look like this:

View attachment 376620

Sorry I should have elaborated, you could do it from the top at an acute angle or from underneath depending on cutter size. What might be far simpler though is to flip it upside down on the bench, and create a ramp jig matching the angle you want with a slot big enough for a template guide, and use the bottom of a wide cutter to machine it in passes from the underneath sliding the ramp jig sideways to complete it. I'll see if I can find a pic that illustrates this.

Ok, found two pics that I hope get my meaning across!

 

[smorgasbord]

Yeah, I was thinking along those lines myself, but the live edge complicates things. The first photo's jig indexes against the edge of the table, which obviously wouldn't work. The second jig could work, but it would have to be over 5' long since that's the length of the table. And that means supports that won't bend when not supported over that whole length.

So yeah, doable, but somewhat involved.

 

[smorgasbord]

Just saw this sleek compact outlet, which comes in a few versions. This one has a cord so suitable for inlaying into a desk (fits in a 35mm hole):

unifit outlet | single

The minimalist outlet. Perfected. Now with an optional self-contained cap, making the back box optional. Installs from the front and removes just as easily - no tools required. Hardwired, self-contained, or corded? Install it your way. Unifit is ETL listed, UL compliant and approved by NYC DOB...

prado.com

 

[luvmytoolz]

Just saw this sleek compact outlet, which comes in a few versions. This one has a cord so suitable for inlaying into a desk (fits in a 35mm hole):

unifit outlet | single

The minimalist outlet. Perfected. Now with an optional self-contained cap, making the back box optional. Installs from the front and removes just as easily - no tools required. Hardwired, self-contained, or corded? Install it your way. Unifit is ETL listed, UL compliant and approved by NYC DOB...

prado.com

I love the mounting design, very nice!

 

[smorgasbord]

@smorgasbord is the prototype top securely fastened to the base? I'm thinking that when the base and the top are actually fastened together, it should be difficult for the end of that top and the leg supporting it to move at all. Eliminating the horizontal movement on the end.

OK, so side projects are done and I'm finally able to get back to this way more fun project.

Used some heavy duty double stick tape, and the base still twists. At the table front edge there's about +/- 1cm of travel, maybe a bit more. Looking closely, the bottom stretcher (100mm x 45mm cross-section) is twisting along its slightly more than 1 meter length. Now this is cheap softwood salvaged from pallets, probably pine, so the actual base made from cherry should be stronger. But, I don't know that it's still going to be strong enough.

What I'm trying now is that little cross leg, as shown in the Nakashima desk above. But, interestingly, on the desk whose design inspired mine, he doesn't have that cross-leg. Then again, his top isn't as wide as mine. I'm certain that the joints I've built in the prototype are solid and that there's no movement there - it really is a torsional twist in that bottom stretcher. I'm thinking/hoping the cross-member will plant the "far" end of the stretcher firmly on the floor and with the weight of the desk holding it down, that will prevent twisting.

If not, I'll have to judge how much it improves and decide whether the cherry will add enough rigidity. Or, go for a different design, which would probably be a smaller-scale slab leg at the far end instead of that angled upright. One issue I have is that I'm working with two slabs from the same cherry tree, one for the top and the other cut up for the base, so I don't want to mess the base up and then have to find other cherry boards that kinda match color and grain-wise. I suppose I could splurge on some other cherry and build a prototype from that....

 

[smorgasbord]

The little foot thing helped, but it also highlighted that my prototype isn't quite square, and that's probably causing of the issues. So I think I'm going to take a chance and build my original design. If I need to add the foot that's not so bad to do, and if I need a whole new design, well, that's life.

Separately, I talked about this before, but the slab is about 1&15/16" thick and we want it more like 1&⅛" thick. One my local hardwood suppliers has a one of those manual CNC things - basically a big router on a table gantry. They can take it down for me at $150/hour and think to do just one side will be under an hour. So, outside of the hassle of getting it down there and coming back to pick it up, I think that's going to be better than building a router sled and taking it down in my shop. But maybe someone could convince me otherwise?

 

[rvieceli]

@smorgasbord My sawyer has one of those and it does a good job of flattening slabs and reducing the thickness. An experienced operator should be able to give a smooth and decent result.

Ron