The ToadStool Table

[wtnhighlander]

OK, I promised to do a journal on this, after "teasing" it in another thread.  I finally got started, and am now proceeding along at my typically glacial pace.

First, material acquisition. I tried a new supplier, as they are open Saturdays, which let me avoid missing work.  The prices were decent, but there are a couple of drawbacks.

• The place is NOT a sawmill, but a "Value Added Reseller". They buy wood from guys like @Spanky and do some sort of processing to it. All their stock was S3S. I prefer rough 4/4, because my work pace means the wood has time to move between milling and assembly. If I start with rough, I have more materials to play with in case a second milling becomes necessary. Also, I had to plane it all anyway, because the thickness was not consistent.
• Ownership of the place in in transition. As a result, no replenishment of stock has been done for a little while. I had to scrape the bottom of the proverbial barrel to find enough cherry with color. At least there was plenty of oak. 

 

 

The design of the table top calls for two layers, the upper of red oak, and the lower of cherry. To account for contrary wood movement, the disks will be attached only with screws in elongated holes. The grain will be aligned so that expansion and contraction occurs in the same direction, which should minimize the seasonal differences in disk size and shape. The cherry disk is slightly larger in diameter to create a contrasting rim for the oak.

As experiment, I tried two methods for cutting the disk. On the oak, I used a jigsaw to rough out the circle, following up with spokeshave and block plane to reach the line. (ignore the background clutter. I'm STILL transitioning into the new space!)

This went pretty well.  But since I just HAD to try a different technique, I went with a trammel-type circle cutting jig an a router on the cherry disk:

 

 

I think I'll go back to my spokeshave. Aside from being annoyingly loud, and incredibly messy, the router setup was no faster, filled the room with smoke of scorched cherry each time I paused to reposition myself, and had a far greater potential to go sideways if the jig happened to slip.

My router has no dust collection port, obviously:

Now I have two concentric disks, still a little larger than intended, just in case. If smoothing and edge profiles go without a hitch, I doubt the client will argue about getting an extra inch of diameter.  Next step is to smooth the disks and create the support structure underneath.

 

[Chet]

How about a third and untried option of wasting away just shy of your line with the saw and then using the router and trammel to get to your line.  might have created less smoking on the cherry.   Kind of an in between the two techniques you used.

[wtnhighlander]

1 minute ago, Chet said:

How about a third and untried option of wasting away just shy of your line with the saw and then using the router and trammel to get to your line.  might have created less smoking on the cherry.   Kind of an in between the two techniques you used.

That method is likely to come up during the edge treatment. But maybe not, as the profile is simple enough to make with spokeshave and block plane. That router mess took longer to clean up than it did to make...

[Chet]

2 hours ago, wtnhighlander said:

That router mess took longer to clean up than it did to make...

Messes are like that.

[Chestnut]

It is odd to me to have the cherry be on the bottom but it's what the client wants. Someone is going to find that in 100 years and be confused as heck.

[wtnhighlander]

Agreed, but this is an oak-loving client. Cherry is just for contrast, and will receive the lye treatment that I demonstrated in a previous journal.

[wtnhighlander]

Quick update:  over the past several days, I have had a few minutes here and there to work on this project. Progress so far includes roughing out the tabletop support braces:

 

... and calculating the cut angles for the base staves:

 

I am currently in the process of cutting 24 stave blanks to uniform dimensions, so I can use a pair of jigs (sleds, really) to form the tapered, angled cuts.  Doing this with machines, rather than the old-fashioned, hand tool way, means that starting with completely uniform parts is critical.  Transferring the angle is critical, too. Any error will be multiplied 24 times, so pucker factor is high....

In the image above, the circles represent the ID + wall thickness of the large and small ends of the cone. The angle remains the same along the edge of each stave, but the width changes. Using a drawing like this makes it simple to transfer the angles and dimensions using gauges and dividers, much more accurate than reading lines on a ruler.

 

 

[Chet]

3 hours ago, wtnhighlander said:

Any error will be multiplied 24 times, so pucker factor is high..

I watched a video on this and he talked about how you fix or make adjustments for errors that you may have made during the process.  It was about a year ago but I can't think if it was Fine Woodworking or something on youtube.  I wish I could remember because it might be of help to you.

[wtnhighlander]

Finished a nice stack of blanks, squared and cut to length. Unfortunately, the S3S stock is not all the same thickness, so a trip through the planer is in order before I cut the angles.

[Coop]

I’m glad your geometry is better than mine. Looking darn good so far. This is going to be fun to watch. Glad it’s on your work bench and not mine! 

[Mark J]

20 hours ago, wtnhighlander said:

Progress so far includes roughing out the tabletop support braces:

How are you managing the intersection of the tabletop support braces?

[wtnhighlander]

3 hours ago, Mark J said:

How are you managing the intersection of the tabletop support braces?

They are lapped. A notch half-way across the width of one intersects an opposing notch across half the width of the other. Like how kumiko screens are made.

There is probably a technical name for that, but I don't know it.

[RichardA]

Ah so!

[wtnhighlander]

Boom.

All the major components roughed out. Now for the slow part...

[davewyo]

Coming along nicely, Ross.

It'll probably go quicker than you imagine.

[wtnhighlander]

Thanks, Dave. I'm just relieved to be through the making of the coopered staves. All that figuring to get the correct angle seems easy (and it really was), but when it comes to cutting away about 40% of the 2 dozen carefully-made blanks, the tension was pretty high. Fortunately, marking my "test blank" with blue tape, ala @derekcohen, made it simple to align the fence on the sled I built, and achieve consistent, repeatable cuts. I have some process photos, but will have to wait until I travel to civilization tomorrow to upload them. My home is in an internet / cell service phantom zone...

 

[Coop]

Looks great already, but the best part is yet to come! 

[treeslayer]

Well done Ross, i'm really liking this build, very unique and its going to look awesome when its done, any ideas on finish yet?

[wtnhighlander]

Thanks guys. I just stacked it all together for the pic, but I kind of like the braces on top of the cone. If it didn't change the height so much, I'd add a plug in the top of the cone for then to attach, rather than letting them in to the sides of the cone. Maybe next time.

Dave, the finish will be the same as the bar I made for this guy last summer. Cherry will be treated with lye to get that deep red color, and the oak will be grain filled with Plaster of Paris, dyed black, and a 50/50 mix of Minwax  Natural and Provincial (I think. There's a lot left from last time). Wipe on poly to top it off.

[Coop]

Without letting the cat out of the bag, I bet you have a plan for attaching the top to the base? I don’t dare to ask about the space between the coopered boards. Bondo would be my simple answer but probably not? 

[wtnhighlander]

Coop, the top of the pedestal will be notched to accept the cross-braces, and then pinned with a few screws, nothing too fancy.

The space you see between the staves is just wood being wood. It closes up nicely with a little pressure from a band clamp in the middle. I still have to make a base plate that goes into a dado around the inside of the large end of the pedestal. The plate will hold 3 leveling feet to deal with uneven floors, and possibly some ballast to conterbalance the top. At this point, I'm not sure the balast will be necessary, but I planned for it, anyway.

Before adding glue, I will tighten everything with band clamps, then wrap it in packing tape so the staves stay together like a tambour. Then I can cut the tape along one joint and unroll it to add the glue. The few strips of tape in the photo barely held it together enough for me to stand it up.

[RichardA]

Damn young'un, you're making @chestnut look like a turtle.  You've really knocked this out pretty quick.  Ya done good.

[pkinneb]

wtnhighlander I am trying to wrap my head around how you cut these at a taper...can you elaborate? Did you use the bandsaw?

[wtnhighlander]

6 hours ago, RichardA said:

Damn young'un, you're making @chestnut look like a turtle.  You've really knocked this out pretty quick.  Ya done good.

That's a stretch. All I had to do was cut a couple dozen sticks...

[wtnhighlander]

2 hours ago, pkinneb said:

wtnhighlander I am trying to wrap my head around how you cut these at a taper...can you elaborate? Did you use the bandsaw?

It is really much simpler than it seems, and I did it on the table saw.

After finding the proper angle with my circle layout, I transferred that angle to the ends of a stave, using blue tape, and setting the width of the cut from the center line, so as to keep the grain centered in the tapered stave. This photo shows the tape on the wide end of the stave:

 

The angle & width of the narrow end were transferred in the same manner, again from the center line.  Once both ends of the first stave were marked, I transferred the same cut angle to my table saw blade. I just used a bevel gauge, but if you do the math on 24 parts of a circle, it comes out to 7.5 degrees, I think.

Once the blade is at the correct angle, I made a plywood sled with a runner on it. Passing that through the blade put a duplicate angle on the sled base. All that remained was to align the blue tape with the edge of the sled, and set a fence against the opposite side of the stave.

Aligned like so (sorry for the blur):

and repeated at the opposite end. I screwed on a fence behind the stave, added a stop block at the trailing end, and a couple of toggle clamps to hold the stave in place. Looks like this before adding the clamps:

 

 

Then it was a matter of running 24 "left" edges through the saw, moving the fence to align with the "right" edge, and repeat. The combination of angled blade and angled sled fence produces the tapered stick with beveled edges. To be truly complete, I should have cut bevels at each end to counter the "lean" of each stave toward the center of the cone. But that bevel is so small, I just skipped it.

With all the sticks cut, I lined them up with the narrow (inward) side down. Running some tape along the top and bottom, I could (sort of) roll the cone up into shape.

 

Doing this alone proved to be a challenge, so I switch to drawing it together with band clamps. Before I unroll it to add glue, I will essentially cover the entire outside surface with packing tape.

 

This may not answer your question clearly enough, but I did shoot some video, so maybe at the end I will compile a video "how-to" that does a better job of explanation.