A Tea Table Post

[4DThinker]

Working on the legs for now.   One step at a time.   Here I've tapered the legs from top to bottom.  Starting at a little fatter than 7/8" and tapered down to a little fatter than 5/8".  Essentially a .125" taper depth. 

Without taper as they look now.

 

With taper:

 

Used the fluting toolpath and an array of lines 1/16" apart.  I'll have to figure out how to prop the leg up after tapering one side to do the other side.   Any opinons?

4D

[lew]

2 hours ago, 4DThinker said:

I'll have to figure out how to prop the leg up after tapering one side to do the other side.   Any opinons?

No experience with actual CNC work. I used to substitute in machine shop every now and then and watched the kids make CNC projects. Maybe anchor the thick end on the table and shim what will be the thinner end with a .125" shim. Then add a couple of supporting shims?

Edited May 18, 2023 by lew

[4DThinker]

Thanks Lew.  Any opinions about the taper vs non taper? 

4D

[lew]

1 minute ago, 4DThinker said:

Thanks Lew.  Any opinions about the taper vs non taper? 

4D

For me, I like the taper. Does your CNC have a Z axis?

[4DThinker]

X.Y, Z, and A (rotary). I can also clamp boards at any angle between horizontal and vertical.  For that matter I could use my adjustable angle clamping jig to do the taper cuts.  5 degrees for the taper on the first side, and 10 degrees for the second side.  Actual angle stated is just a guess until I check my CNC software. 

4D 

Edited May 18, 2023 by 4DThinker

[lew]

The reason I was thinking about the Z axis was along with the slight taper, maybe mimic the table top underside ellipse to soften the top edges of the leg at the same time you are doing the taper.  

[4DThinker]

Across the width of the legs the curve of the top underside would be so minimal that most wouldn't notice unless it was exaggerated. I had an earlier though about rounding the from end of the foot to match the curve of the top above it, but an 8" radius over 5/8" again is barely noticeable.  Exaggerating that curve to show up better just looks odd. 

 

I do agree that the leg design can still be improved.  Perhaps rather than a flat taper surface I do the ellipse curve on the sides from top to bottom where the ellipse peak would meet at the foot front vertical edge.   It would be more difficult to create a toolpath to do that, but I'm sure I can figure out a way. 

Very subtle, but does transition around the foot front. 

4D

[lew]

Now this is just me, but I think this edge/corner, on both sides would look better if they were softened/radiused 

[4DThinker]

Image of the table with round top.  No 3/16" roundover edges yet, but put together to compare against the 9 sided top images. 

Round top: 

 

With 9 sided top:

 

4D

[lew]

Seeing them side by side makes it even more difficult to pick!

[4DThinker]

The edge of the round top will eventually be 3/8"d bullnosed to relate better to the detail on the post.  Leg design is still up in the air, but should make a difference in the overall composition.    

When I taught furniture design the final project for the Workshop 1 class was to design and build a small table with emphasis on detail continuity between the top and the base.  Example projects I've posted on my blog.  1st example is a table I have next to my desk just large enough to keep my phone and smart watch on while I work at my desk. 

https://4dfurniture.blogspot.com/2022/04/woodworking-education-tiny-table-1.html

There are 3 other same tables linked to at the bottom of that post.  The first is the only one I actually built, although I've cut out the top for the other 3. 

4D

[lew]

All your tables are really neat. So many details I would have never thought of 

[4DThinker]

Thanks Lew.   A side effect from teaching furniture design for so many years.  In 2007 I was a judge at a national student furniture design competition. High School and College students projects among the entries.  What made the difference between category winners and runner ups was the level of detail continuity and thoughtfulness in the designs.  All projects looked great and had been pre-screened to get to the show.   Close examination was needed to spot where thoughtful and usually subtle detail choices were made to refine the design.    This is the curse I suffer that makes me know the legs on the pedestal table aren't finished yet.  Almost ready to start over with them to see if a new shape can better relate to the curvilinear post and top.  These initial legs were restricted in shape by the available wood I had to cut them out of.  Raw outlines that I hoped I could refine later to work with the post and top. 

4D   

Edited May 19, 2023 by 4DThinker

[Grandpadave52]

Like Lew, seeing both tops, makes it even more difficult. That said, I'm waffling back to the 9-sided. Personally I still like the leg design with the pedestal. Agree they need some finish touch, I'm just not the one with that vision to say what.

 

Enjoying this design, build process. Thanks for all the pictures. I'm a visual kind of learner.

[4DThinker]

Another leg version to go with the circular top.  Just a quick digital sketch.  Elliptical curve. Bowed top and bottom surfaces.

 

Slight variation:

 

Edited May 19, 2023 by 4DThinker

[4DThinker]

The groove on the leg sides can be cut from leg to leg around the base of the post where the legs connect.  A way to literally connect leg detail to post detail.  

The groove is done with a veining bit.  Back to back roundover cuts 3/16" deep of a 1/4"r bit.  Leaves an end on the arc just as the roundover top and bottom cuts on the legs do.

4D 

[lew]

I like that!

[4DThinker]

The only challenge with this last leg is cutting it out.  As the curve on the edges runs around all but the dovetail end I can't clamp it down anywhere on that edge.  It is a two sided cut and cutting one side is easy.  But as the curve cut on the edge runs to the center it means when cutting the curve from the other side it cuts all the way though the wood, meaning the piece would be loose other than on the dovetail end, assuming that end is not at the edge of the board the leg is cut from.  Scratching my head trying to shake out an idea to simplify cutting it out.  Almost sure I hear some loose change rattling around up there. 

4D

[lew]

Maybe screw a waste block onto the "bottom" of the foot- the face that will set on the floor. Use it to clamp that end of the leg.

[4DThinker]

36 minutes ago, lew said:

Maybe screw a waste block onto the "bottom" of the foot- the face that will set on the floor. Use it to clamp that end of the leg.

Currently the rounded over front and back of the leg also wraps around the bottom.  To declare "the leg ends here", rather than just let it look like it was chopped off at the floor.  A screw in the middle would be hit by the router bit.  Depending on the screw either the bit would break or the screw would be cut through.   As I've pondered the challenge the danger of the board being loose only happens at the very end of the 2nd side cut which is rounding over the edge with a ball end bit. The bit has to move past the centerline by 1/2 the diameter of the ball end.  The cut from the 1st side would have already removed 1/2 the edge plug another 1/2 of the bit diameter.  That mean the board would be "free" other than at the dovetail end when there is still 1/3 or so of the edge toolpath to do. 

 

I'm contemplating the best strategy to break up the toolpaths on the 2nd side. If I just cut one edge first I can put a clamp on from that edge to then run the other two edges.   Or do everything but the bottom edge, leaving it to keep the board attached.  Then put a clamp over the leg while the CNC cuts that bottom edge. Layout the cut so when the CNC approaches that bottom end it doesn't have to cross over any clamp I've put on. 

 

One thing most don't realize when considering to buy a CNC is that holding down parts is often the most challenging part of the job. Particularly when doing 2 sided cuts that include edge profile cuts. 

4D