Radial arm saw setup for scarfing plywood. (Blade is removed and drill chuck is holding the drum) Scarfed plywood is on the table. A drum sander is the BEST way to scarf plywood and reduce your longeron thickness. (My opinion) I got this drum sander from Sears. The drum and paper were used on their oscillating sander. Make your own setup from plans and save yourself from buying a radial arm saw.
This is the point where your longeron goes from 3/4"x 3/4" to 3/4"x1/2". Make your longerons too long so that you can position this transition properly. This is also another example of why reading the plans well before jumping in can save you from fudging up your hard work.
I let one peice of wood slip by my inspection when I picked it up at Wick's. This piece had a wavy grain that was just in tolerances. (See book references above. I ended up using this piece for less critical members. Just to the right of my head are the spar caps for the main spar. (Standing vertically) These were purchased at Wick's along with the rest of the wood.
Just even with my hat are pre-molded spar caps from Wicks aircraft supply. Unfortunately Wicks no longer makes them. Please feel free to put your "two cents" in regarding how much you'd like to see them make them again when you place a wood order to them. I hear that they are a real pain to make from scratch.
The only part of the woodwork that proved challenging was the installation of the spars. It was a good idea to do one spar at a time as the glue had begun to congeal by the time I had the main spar coated and where I wanted it. Make sure that you have plenty of epoxy and everything that you need to do the job before proceeding. Getting the glue to completely fill the joints is interesting even if you do it the way the builder's manual says to!
Having the main spar installed makes aligning the rear spar much easier. It also allows you to get that two degrees on incidence the manual calls for.
Main spar prior to plywood skinning. The curved blocks require great attention to get a perfect fit.
WOOD CONSTRUCTION
HIGHLIGHTS OF WOOD CONSTRUCTION
Here's the spar ready to have it's plywood skin glued on. You have to scarf and join the plywood for it to cover the length of the spar.
Shown lower right is a router with a counter top bit trimming the excess plywood from the spar. It is also used to cut the lightening holes in the fuselage.
There are plans to build various scrafing tools. Here's a tool I made for fun just to see how well the idea worked. It was made from steel tube and used cheap bearings mounted in aluminum blocks. The drill was locked in the "on" position and it did alright. Note the slots used for mounting and adjustment.
Obviously one would need to practice on scrap before playing with expensive aircraft plywood.
There is no shortage of pictures of WAR fuselage boxes, spars and the like. What you don't see a lot of are the tools and setups for doing the wood work. I'll use this page to fill that gap. WAR plans are mostly full size and well detailed. Things like grain direction are shown on the plans so it's really a no-brainer.
There's no way I could fit everything you need to know in a few pages. There are plenty of guidelines in the books mentioned below. EAA publications such as Sport Aviation often have a tech page section covering the basics too.
The tools need for woodworking are listed in the builders manual. I'll add my opinion on tools I purchased and what I'd do differently. The following list is not all of the wood tools you'll need. The most important tools are...
BANDSAW. This is the primary tool you'll use for wood cutting. It offers excellent control and is used for fuselage upright, diagonals. ribs, etc. Just get a single speed wood cutting bandsaw with a decent throat depth (12" is nice) and a real electric motor. (Not some little toy motor) Expect to pay $100-$250. Make sure that there are many blade styles available for the saw you get. I got the top 'O the line Sears variable speed which could cut both metal and wood depending on the blade. What I should have gotten was a bandsaw that used a more common blade length. In the end, the weak little DC motor crapped out on me and I rigged a AC motor to fit. Although it did OK on wood it just couldn't cut metal that well. If you're on a budget, a jigsaw works fine on the metal anyway.
BELT SANDER. A vertical belt sander is one of the BEST tools for your shop you'll find. You'll use it for finishing to a line after rough cutting on many parts. (wood and metal) All you need is a cheapie 1" width sander with a platen. The type shown at right is best IMHO. Having the belt far away from the mast helps for certain things. Get one for your plane's wood and another for everything else to keep your wood clean. A little oil or grime on wood makes for substandard glue joints.
TABLE SAW OR RADIAL ARM SAW. You'll use either of these for cutting your aircraft ply sheets and for most of the jig work required. Some of the heavier materials such as spars will get cut/trimmed also. A radial arm saw is a bit of a luxury and really not required. A small, cheap table saw is all you really need. Be REALLY careful when using a table saw or arm saw. It is waaay to easy to have an accident and loose some fingers/flesh. Get a helper when cutting plywood or any large/long cut.
ROUTER. Used to cut lightening holes on fuselage. If your'e very careful and use a router mounted to a routing table you can use it to cut out the holes in your plywood ribs.
DIAL CALIPER Get a cheapie for measuring plywood, wood, etc. Enco sells them cheap for around $12-$20 for a value line 0-6" model. Saves time and possible screw-ups.
SCARFING TOOL. This is used for joining sheets of plywood. See pictures below. The belt sander style is best. You can make a scarfing tool fairly easily. For scarfing logerons (3/4"x3/4" spruce) You will cut the angle with a table or arm saw, use a plane then glass or razor scrape the joining surfaces prior to glueing.
This book, EAA Wood and CAM 18 are the two BEST buys you can make for the wood building aspect of WAR aircraft. Tony Bigelis' books are also excellent. The builders manual gives a little advice too. I don't like the scarfing jig in the WAR builders manual. It uses a table saw for making the scarf. A drum sander is the best way to go.
Flush trim bit for router. I've heard it also called a "countertop bit". Note the bearing at the bottom. You'll only need this style of bit for your WAR project.
Your builder's manual lists many of the tools needed But I'll list a few that seemed very helpful if not essential. Carbon paper is great for tracing ribs, etc onto the plywood. Get a hefty supply of 2" clamps, 4 to 6 4 " clamps and at least 6 to 8 6" clamps. Heavy weights such as concrete blocks come in handy as well as clean wood for backer boards. (Between blocks and A/C wood. A stapler that handles 1/2" T-51 staples is great and much faster than hammering brass tacks. Get a forked screwdriver for removing the staples. A 1"x2"x2' block of oak or other hardwood is nice for backing up wood when planing scarf joints. (Longerons) Glass plate or razors are used to scrape woodwork before joining.
Many WAR aircraft's woodwork are glued with T-88 epoxy. This works great where the mating surfaces are not exactly perfect. It's gap filling qualities are good. Resorcinol is an excellent glue for adhering ply skin to your outboard rear spar sections. It is also awesome for laminating. It seems to hold much better than epoxy in these applications. Clmaping/pressure is important with this glue as it's gap filling properties are poor.
One area of trouble you will encounter is locating outer spar material for the main spar. The plans state that only solid material not laminated is to be used. Aircraft Spruce will very reluctantly get this for you but there will be a wait and the cost will be high. The problem with using laminated material is that the bolt holes for the spar fittings go through or very close to the glue line,
