Morticing table saw

Jim Hiltz, Jim MacLean, Shawn, Keenan, Arno, Miles, Rick, John, Lawrence, Paul

Leo demonstrated finishing a piece of Mahogany using the Spray -on vs Paint- on Shellac technique
Half the board was done with each technique.

Spray on a thin 4:1 dilution of Blond shellac
Alternatively paint on the shellac. Use a dry brush method. i.e Apply a layer of shellac and keep brushing the surface until it becomes almost dry

Let it dry

Then apply a small amount of Methyl Hydrate (Methanol best but hard to get) and sand the surface to produce a beading or peeling as it melts the shellac and then add a little paint thinner and sand this shellac peeling into the grain
Build up 3-4 layers or more
Do this in a low humidity room . If it is humid , water will bead on the surface. (This also applies to Lacquer)

Once the grain is filled (after a few coats) , then start sanding to produce a finished surface
Start with 280 grit and sand using paint thinner  (not water)
Go up to 2500 gradually:  wipe off each time with paper towel before going to the next grit
Then use a rubbing compound (car waxing rubbing compound)
Then use Cesium Oxide (this will still cut the surface)
Then use Carnuba wax-small amount (this does not cut)  and again paint thinner to rub it on
The result is identical whether you spray or brush on the shellac. Spraying has the advantage of allowing you to do irregular surfaces better, but the disadvantage of having to clean the spray equipment thoroughly.


We then went to the Table project. This is a long-term learning project.

Some people had drawings prepared, John and Arno in particular
Arno brought a good supply of Maple and Birch boards for everyone.

Step 1: The top:determine the thickness and dimensions

If you want a thickness of 3/4 inches, the boards have to be dressed to 13/16 to glue up
They will then be planed to 3/4

Assess the rough boards for suitability.
Choosing wisely, Cross cut the long board into shorter pieces that will be sufficiently long to make the top dimensions that you have drafted

Then one rips these pieces into narrower boards
It is usually necessary to rip off various widths so as to avoid defects and knots.
The result is an assembly of narrow boards to glue up. One can use shorter segments of the "bad" pieces for the drawers, runners etc.

In glue-up, Pay attention to end grain orientation. The end grain of each board should be in opposite directions so as to avoid "cupping". Nonetheless, one has to sacrifice this "ideal" approach so as to get the best match for the top surface of the finished glue up. One has to play around with the boards to get the best result.
•••Remember that the surface grain should go in the same direction as well so as when planing, tear out is minimal. That means that you need to know how to figure out the grain direction of a board !

Tips:

Use chalk -not pencil-to rough mark boards for initial cutting
If you need to get three boards from a piece that is pretty narrow ( eg for the legs), mark out the leg tapers on a cardboard template and then apply this to the stock piece and cut it with a band saw. This can optimize the use of your stock.

Keenan and John..letting on that they know what they're doing

Arno's design in the rough

John's design-clearly the best in the drafting phase (so far!)

John, Paul, Jim Hiltz, Jim MacLean, Shawn, Keenan, Arno (Rick was ill tonight)

Paul had a long 1.5  x 1.5 inch bed support and asked how to match up a series of 26 drilled holes from the original (broken) piece, to the new piece

Leo suggested using dowel pins. This worked well.

Shawn brought a turned oak bowl-wood salvaged from a Louisbourg cannon mount. Leo showed how to use a wire cord to burn a decorative line near the top of the bowl, which highlights the turning

We discussed the wisdom of doing a Table project and everyone was interested in this. This involves making a small end table. The whole process brings many woodwork skills into play.

1 Decide on the dimensions: height, length and width  of the top , drawer opening
2 Make a drawing -three projections of the project (Orthographic drawing)
3 Select the wood and make a material list eg 4 legs of 30 inches  each would need 120 inches of that wood dimension (finished length )


Leo discussed the Golden Ratio  (10/6) and Fibonacci number series: 1,2,3,5,8,13,21,34 etc ( the previous two numbers are added to get the next number). The Golden ration and Fibonacci series are seen in nature eg. length of the leaves on a fern, length of the bones in a man. The 10/6 dimensions seem to be most pleasing to the eye :eg the typical picture frames, desk and table tops  use this ratio

Leo discussed filling wood
Cherry, Maple,Beech need no filling
Most other woods need filling as the grain pores are open

Shellac can be used to fill--(epoxy is good as well)
Sanding blocks made from layers of ceiling tile glued together work well
Apply a thin coat of shellac to the wood
(Use shellac flakes dissolved in Methyl hydrate in a 4:1 ratio -4 volumes  of the methyl hydrate to 1 volume of the flakes)
Once dry, dab on methyl hydrate and sand the shellac layer until it begins to peel-roll
Then  dab on Paint thinner and sand the rollings back into the wood to fill the grain
Do this repeatedly until the grain is filled

***Minutes from 2012-The Table Project

We began work on the table project.

Step 1 Sketch a design
Eg top 18x16,, drawer, leg shape

Step 2 Material list

Choose stock for top: 6-8% moisture content is best

Leo chose a large board of cherry and cut it into 18 inch pieces--three for the top
Flatten one side on the jointer, choosing grain direction to minimize tear out
Flatten the second side on the thickness planer again being careful with grain direction

Leo demonstrated a jig to use the jointer as a thicknesser..see photos:

When one side is flattened, run the board along the table saw to make a cut along the top and bottom edges; there will be a rough section left in the center; run the board along the sled jig to remove this section until that side is flat and it should be parrallel with the opposite face now.




Next joint the edges of the boards.
Place the first board “marked side” in to the fence and the next board “marked side” out so that any discrepency in the jointer fence is cancelled out as the boards meet.

When boards are planed, align them with the end grain patterns alternating up and down if possible but the main thing is to get the top surface matching for pattern and grain direction.
Line them up and draw a reference mark along the top so that they can be reassembled correctly.

Glue up the panel , making sure the edges are flat and the joints flush.
Pinch together one end of the panel with a clamp. If the opposite end separates, the joints are not good.
Leo demonstrated his new jig for bowl turning.
He went over carbide blades, describing microcrystalline manufacturing.

Leo described how a thickneser works.
There are rollers that drag the wood through and the cutter rotates on top of the board.
The rollers tend to tip the board as it enters and leaves, leaving snipe at both ends.
The best machines have four rollers..two at each end so that the board is kept level as it rides along two rollers on entry and again on exit. Click the picture below to see a sketch of what this means!

From Table project

We need to make the panel and turn four legs by next session.

Table project