Sources of Materials
Steel building board
 The
board on the left is 24" x 60". It is nice having extra room to
place
fixtures and on-the-fly magnetic jigs.
The
Great Planes board to the right in this photo is 18" x 48"
— large enough for most aircraft fuselages up to
.46 size. Theirs is the first magnetic system I used and immediately I
could see the potential if done properly.
I don't like the Great Planes system. It is over-priced, comes with
way too few magnets and the plastic accessories are junk. Make your
own system instead.
I went to a local metals supplier and asked them to cut 3 pieces of 22 gauge
stainless steel. The largest piece was 24" x 72". The other
two were 12" x 36". I wanted a small board so I could work
on tail feathers while building a wing or fuselage on the large board. The
second small board hangs on my shop wall to
store magnets and fixtures.
Unfortunately, I found out that magnets don't stick to stainless steel.
The dealer swapped the boards for the same number and sizes of plain steel
that is coated to receive paint. The coating seals the boards from the
environment so that they won't rust. After a full season mine is
showing a small amount of tarnish which is good because tarnish is not a
problem and it's not rust.
I don't know this for a fact, but the surface pattern of galvanized steel
looked like it would be distracting while building over it. I didn't
feel it was a good choice.
No matter what type of steel board you buy, make sure that magnets will
stick and that it will conform to the workbench top which should be dead flat.
My workbench is already flat so I didn't need to buy a sheet of armor.
I'm very pleased with the thickness of my board because it conforms well and
I can move it easily.
I clamp the board to the table top when I'm doing something that causes the
board to move such as sanding a structure trapped inside fixtures.
If the steel board you buy can rust, then I suggest you protect it with a couple
coats of good car wax or a coat of Rustoleum paint.
Moving the magnets over the board will scratch the wax or paint off
— another reason to use an inexpensive pre-coated board.
I draw lines on the board with a Sharpie marker. Wipe it up with
alcohol. The longer the lines are down, the harder they are to get up
or a stronger solvent is necessary.
Magnets
 The
magnet that I have found most useful is a latch magnet. These can
usually be found anywhere cabinetry supplies are sold, but will be expensive
if you buy them that way.
I
purchase part number CA41LWH from
The Magnet Source. Each of these magnets is advertised to have 12 lbs of
holding power with the metal plates attached. I didn't measure the
actual pull, but they stay in place - even when bending 3/8" square spruce.
The magnets are much less powerful without the plates, but are very useful
in lighter duty applications.
40 magnets will not get you very far when you get deeper into using the
system.
If you're serious about building then I suggest you order 200 magnets to
start. A set of 20 fixtures uses 80 magnets. Once you start
building a wing using 4 or more magnets to properly align each rib plus
magnets to hold the spars, leading and trailing edges you'll understand why
you need a lot of magnets.
Fixtures
I make fixtures from aircraft plywood. They will last forever and can
be passed to somebody else in the event you aren't immortal like I am. You can use any material you want though; masonite, cheaper plywood, plastic sheet, etc.
The vertical presses are made from hardwood but would be fine from aircraft
plywood.
Hardware used for fixtures
You can get all the
hardware you need from Lowes or Home Depot with the exception of the #2 hardware used
to attach the vertical presses. Pick these up at your local hobby
shop or from
Micro Fasteners.
You'll need (2 ea) 10-24 x 1" bolts and nuts to attach magnets to the
fixtures. You don't need washers.
The vertical presses are held in place with a 2-56 bolt, washer and lock
nut.
The press part of the vertical press is a 10-24 x 2" thumbscrew (or whatever
bolt head shape you feel most comfortable turning by hand).
In this series
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