Sawing Spruce Boards Into Spars

 I've finally started sawing spars from my stack of spruce.  I started by inspecting all the boards and picking out the shortest ones with good sections long enough for the 2 wing spars.

The first step was to saw 2 boards to 4" wide.  The spars are 3 5/16" tall.

The boards are 17 feet long and I was able to saw them by myself with 2 sets of rollers on each side of the saw.

The next step was to re-saw them with the bandsaw.  Shopsmith makes a 5/8" blade specifically for re-sawing boards.

I split the board to have a 1 1/4" wide Aft Wing Spar and a 1/2" wide Forward Aileron Spar, plus an extra 1/8" available to plane off each.

I made a fence for the bandsaw with a piece of 3" angle iron clamped to the table.  

I used the featherboard to hold the wood tight at the bottom.  Shopsmith makes a feather board that you can stack up to 4 high just for this type work ($90).

The instructions for the 5/8" blade were to run it at 500 RPM to prevent overheating.

When sawing long boards a wedge can be useful to keep the saw cut from closing and binding the blade.  It wasn't needed with the bandsaw.

The kerf is very clean and narrow.

It measured 0.030" wide, about 1/3 the width of the 10" circular Rip blade I used for the first cut.

I went real slow and the first board came out perfect, straight down the board, and straight and square top to bottom.

The second board I must have pushed too hard and the blade curved into the wing spar, leaving extra wood to plane off the aileron spar.  In the end the wing spar would be less than 1 1/4" after planing in order to clean both sides.  

I'll plane it down for another project.  I bought enough wood to rebuild the monoplane wings for our Fly Baby.  The old ones were lost in a hangar fire.  It's licensed to use either the monoplane or biplane wings.  The monoplane wings work better for trailering to events because they fold in about 10 minutes.  This board will make a nice rear spar.

On the 3rd board I decided to try a different approach.  I've never had luck lining up 2 deep table saw cuts to meet in the middle of the board, so I tried a 3 cut approach.  I made a 1 1/2" deep cut, took the board outside and flipped it end for end, then made a second cut on the other edge.

I used the bandsaw to connect the two assuming the blade wouldn't wander so far off the cut line.

It worked perfect, 2 nice boards ready to plane down.

You can see below how the blade wandered but never cut into either spar.  They'll both plane down perfect.

I had bought a couple 10' boards to use for the aileron Aft Spars.  The rings were at slightly more of an angle than I wanted.  I got the idea to cut the board in half at about the angle of the rings.  Then I used this surface to re-saw the boards.  My first cut was along the line running almost corner to corner of the original board.

It worked perfect.  I used the wedges to cut, quarter sawn, 1 1/8" x 3/16" laminations for the wing tip bows.  I ended up with only a small bundle of tiny wedges for scrap.  I needed 8 laminations and ended up with 9.

Time to do some thickness planing.