Router Plane

Monday, December 26, 2016

Dining/Game Table - #18 Flattening & Sizing the Leaves, Making the Pegs

I could now start running the pieces through the thickness sander to clean up any slight misalignments of the joints and flatten.  I can’t use the planer because it can only do 12 ½” wide pieces and the panel is 16”.

Because I am pushing the maximum size of the sander it creates some problems.  First, it is rated for a 16” sanding pass, but that’s nominal.  Effective width is around 15 ½” so it leaves a little ridge on each side that has to be frequently removed.
Ridge to be Removed from Thickness Sander
Second, because I am at the width limit I can’t shift the piece from side to side which means the glue joints hit the same exact place on every pass and builds up on the sandpaper as in the photo below. 
Glue Build-up on Sanding Abrasive

If very much builds up it causes a nice burn mark the full length of the piece along the glue joint.  The fix is to frequently stop and scrape the glue residue off the sandpaper.  Unfortunately, that is a fix with a decreasing return.  Each time I do clean it up the time before I need to do it again is less.
Temporary Cleanup of Glue

Third, because of the piece width I can remove only about 1/32” per pass which does not sound like much but in one pass that means it is converting over 26 cubic inches of red oak into sawdust.

All in all, it took me the better part of two days to take the 44 square feet of surface area on both sides clean up slight misalignments of the joints and flatten, then rip to final width.   There is still a lot of work to do but this is what it looks like.

Flattened Table Leaves Cut to Width but Not Length

My next step is to cut the four top sections to length.  First choice for cutting a long heavy piece to length would be my chop saw but that won’t work because it cannot cut a piece this wide.  I do have a crosscut sled that makes cutting large pieces work pretty well on the table saw.
Crosscut Sled on Table Saw

I started by squaring up one edge then making a second skim cut.
First Edge to be Square Cut

The cut on the other end to finish length is done in a two-step process.  First is to make a cut about a 32nd of an inch long using a stop block set up on the sled. 
Cutting Leaf Slightly Long

The second cut is to finished length.  I don’t want to move the stop block so use a spacer 1/32” thick to make that last skim cut.  This way all the pieces will be cut the same length.
Stop Block with Shim Ready to Make 2nd Skim Cut to Final Length

I thought about the next steps and decided rather than continue on with finish sanding, routing the edges of the top then end up installing the pegs that will align the leaves I would start with the pegs.  Once they are all in place I will move on to finish sanding and routing the top edges.  I plan on taking this route in case there is some slight misalignment when laying out and installing the pegs that requires some work on the leaves.  No sense in doing the finish work twice.

Before I actually started drilling holes in the leaves for the alignment pegs I did some testing.  I sure don’t want to make any irreparable mistakes on one of them.  That would mess up more than my whole day.  Starting with some scraps from the leaves I laid out three peg locations then using a self-centering doweling jig drilled 1” deep by 3/8” diameter holes in both pieces.

Next came the pegs.  I had some 3/8” fluted dowels that I thought might work out.  Some five tries later I had developed a shape I was happy with.  I was not happy in how they looked or the material hardness so decided to try a different wood.  Since the table is out of red oak and I have a lot of scraps to work with I tried that.  It worked out better but oak is an opened grained wood and after turning it on the lathe I decided I wanted a close grain wood.  Both maple and cherry came to mind but because the maple is soft maple I opted to go with cherry.

Peg Tests

Last test is using the final peg design install them in the leaf scraps and check to see how they come together.   Here is a pair of photos, the top one has the pegs installed in one piece.  The other has the holes that will go on the pegs.  The bottom photo shows what the two leaves when almost pushed together.  Sizing the tapered end of the pegs is like Goldilocks and the three bears.  You want the pegs to fit just right.  Too loose and the leaf will be free to move around and not be aligned.  Too tight and while it will align it will take a gorilla to put leaf in place or remove it.  It’s a balance that is measured in a few thousand’s of an inch.  Throw in the humidity change between New Mexico and Arkansas and it becomes even more interesting.  Actually I am going to leave them unfinished and removable so if needed they can be easily modified.

Testing the Pegs and Alignment Process

With the testing done I started on making the 18 pegs needed.  They start with a cherry blank 7/16” square.  That gets inserted through the 4-jaw chuck on the lathe.  The green tape on the tool rest has my reference measurements laid out on it.  Since so many pegs need to be made this will help speed things up by not having to measure each one.
Square Peg Blank Ready to Turn

The square blank is turned round and to a rough size.  Here I am using a 3/8” wrench to check the size of the turning.  It works really well; I don’t even have to turn the lathe off to check the size.  When it just slips over like this I quit turning.  The wrench may say 3/8” but it is .007” over. 
Using Wrench to Check Peg Diameter

I transfer the measurements from the green tape by eye then turn the tapered end.
Peg Ready to be Parted Off

The rough peg is cut off and driven through a die exactly 3/8” in diameter.  This is where the 3/8” wrench being slightly oversize is a good thing.  As much as I try it’s really hard to hit an exact size so being a smidge over gives me a little leeway. 
Die for Sizing Peg

The peg is then put back in the lathe for sanding which removes just enough material for a snug fit into the drilled 3/8” holes.  Three pegs down and 15 to go plus a couple extras.  Turning the cone shaped end of the pegs for a final fit will come after I drill the holes in the leaves and do finishing alignment.


Next Up – Drilling Peg Holes & Routing Top Edges

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