How to Mount Silvretta 404 Series
Backcountry Skiing Bindings
Disclaimer:
By using these mounting instructions and templates, you agree
to not hold Wildsnow.com, its owners or associates liable
for anything. There is no warranty for these instructions, and
no support. You are on your own. These are instructions for
mounting an antique binding for display, this binding is
NOT RECOMMENDED for skiing or field use as it does not have
the safety release of modern ski bindings. If you choose
to ski on this binding, you do so at your own risk and agree
not to hold Wildsnow.com, its owners or associates liable
for anything.
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Silvretta 404
backcountry skiing binding. |
Backcountry skiing bindings based on
the "plate" design, such as the Silvretta 404 model
series, are easy to mount at home. Take care to locate the
binding in the correct for/aft position on the ski, be sure
the binding is centered left/right, position the heel unit
correctly -- and you're good to go.
To mount your Silvretta 404 backcountry skiing
bindings at home, follow the directions below and use our carefully
designed mounting template you can download
here.
(Warning: After downloading and printing
template, compare to screw hole patterns on actual binding, as
printing can sometimes distort the layout. If it doesn't match,
tweak printer settings such as scaling, which should be set to
100% or possibly "no scaling.")
The keys to success with home binding mounts
are careful measurement, going slow, and using the binding and
paper template as a substitute for the mechanical jig used by
a shop. Also, if you're new to ski work consider doing a dummy
mount on a pair of dumpster skis or a wood 2x4.
What I'm presenting here is one of many ways
a craftsman could achieve a good binding mount that's authentic
and will look good in a collection display. If you're comfortable
with tools and measurements, you'll probably figure out a few
variations along the way. Whatever you do, remember the idea
is to center the bindings left/right on the ski, and locate the
boot so it matches the boot location mark on the ski.
How to do the deed:
First, you need a good workbench or kitchen
counter. Cover your counter with something liked taped butcher
paper or cardboard. Tools
and materials needed:
- handheld screwdriver with pozi-drive bit
to fit screws that come with the binding (with care you can
use a jumbo philips bit, but pozi is much better, see note
at bottom of this page.)
- electric drill with sharp 5/32 inch bit
(see note at bottom of page)
- electrical tape and clear office tape, and of course some
duct tape
- sharp center-punch, with associated hammer
- long straight steel ruler (wooden yardstick
is not straight enough)
- tape measure
- fine point Sharpie type marker
- 1-hour epoxy
- paper templates
- scissors and paper punch
Step
1 Make sure you know where the mounting mark (aka "sole
midpoint") is on your boots. It's usually a small vertical
line, arrow, or triangle molded into the side of the sole
about midway
between heel and toe. If your boot doesn't have it: Most
of these marks are simply half the distance between toe and
heel, just locate it by measurement. Enhance the mark with
your Sharpie so you can't miss it.
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| Some skis may have such a useful
boot location mark such as this, if so, you won't need
to enhance it. ("3.5" indicates recommenced metric
drill size for this ski). |
Step
2 Find the boot mounting
mark on the skis; usually a small triangle, arrow or line
that's at the approximate midpoint of where you'd imagine
a boot would sit on the ski.
Be sure you get the right mark -- if
in doubt ask a shop rat, or call the seller. Grab your 24" framing square (now you're
a carpenter).
Using a straight edge, draw a set of
nice black lines across the boot mounting marks, so you have
a good visual reference. Line up the straight edge by eye so
it's as square to the long axis of the skis as possible. (If
your skis already have a good boot location mark, you may be
able to skip this step.)
Step 3 Continue doing layout
marks. This time, make a nice long tip/tail center mark on both
skis. THIS IS IMPORTANT, as our whole method of mounting depends
on these marks being accurate. Measure across
the ski and make left/right center marks a few inches ahead and
behind the actual binding location. Connect the marks with your
long steel ruler, then ink a nice long tip/tail center line
using a fine point Sharpie. You'll use this mark to align the
paper templates. Do it well!
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| Use your long steel ruler to mark a tip/tail center line
that extends well beyond front and back of binding. You'll
use this mark to align paper templates, so make it perfect! |
Step 4 Grab a Silvretta
404 backcountry skiing binding, adjust it for your boot, then
snap boot into binding.
Step 5 Set the binding/boot combo
on a ski, and align the mounting mark on the boot over that on
the ski. I usually eyeball this. If in doubt, make a small square
out of cardboard and use it to reach up from the ski to the mark
on the boot. Again, take care that you get this exact to the
nearest millimeter or so.
Step
5 On top of the ski, near the edge, carefully mark the for/aft
location of the binding's front screw holes. You'll use this
mark to line up the paper template.
Step 7 Using the same straight
edge technique you used to mark the boot location, make accurate
lines on your skis showing the for/aft location of the binding's
front screw holes.
Step 8 Cut out the toe portion
of the WildSnow paper template, leaving plenty of paper in front
and behind screw marks, so you can line up tip/tail center marks
accurately. Cut paper from either side of screw holes to make
template slightly narrower than ski. Place paper template on
ski with center marks aligned, and front screw mark aligned
with screw mark/line you drew on ski. Tape template to ski once
it's perfect.
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| Front portion of paper template on
ski (template shown is not for 404). Template has been cut
so it's slightly narrower than ski, but long enough to show
plenty of the left/right center location line. |
Step 9 Now the first moment of truth.
Grab your sharp center punch, and dimple the
exact center of the screw marks. Remove the paper template.
Step 10 Ahhhh, now, power tools! (But
remember: measure twice = drill once, so triple check that your
screw hole marks are spot on by setting the binding on the ski
and sighting down through the screw holes.)
Chuck that sharp
5/32 bit in your drill. (Using a sharp drill bit prevents the
bit from wandering sideways while you drill.) Place a screw
in the binding (with the plastic shoe that goes under the toe
unit) as if it were already in the ski, and use the protruding
screw as a gage to to figure how deep you will drill. Tape a
depth stop to the bit by wrapping tightly with electrical tape
to create the stop. Drill your center punch marks with minimal
pressure, so you don't mash the bit through a ski.
(If you do totally klutz it and drill through a ski, it's actually
not that big a deal (repair with epoxy and P-tex), but it's
considered poor style -- to say the least -- and is none too
good for your kitchen countertop. By the way, if you got the
brakes for the bindings, put them on after you've done the mount,
as they make it harder to work with the bindings.)
Step 11 Screw the binding to the ski
using the front screws. Torque with care as not to strip the
screw hole (don't use a power drill to torque screws unless you're
a tool ace). Start by gently tightening one screw, then check
how the rear of the plate lines up with your tip/tail centerline.
Continue to tighten screws will checking alignment. Sight down
through the screw holes in the binding and first place screws
in holes that align best with holes in ski. If you're confident
about your mount, place epoxy in the screw holes before inserting
screws. Otherwise, do a "dry
mount" first
and only gently tighten screws. Once you're sure you've got it
right, pull the screws, then re-insert with epoxy.
Step 12 With the 404 plate/frame mounted
on the ski, centered and in correct for/aft location, it's now
time to mount the binding heel unit. Go slow, locating this
properly is critical. Cut out the heel section from a paper template,
leaving plenty of the tip/tail center line. Lift the plate, place
the paper template under the rear of the plate, then lower the
plate. Move the paper template to align the indicated mark with
the rear of the plate. Center the template using the tip/tail
line, then tape it to the ski.
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| Locate rear template by lining up with
rear of binding frame/plate as shown here. To do so, use
a corner of a square piece of paper or cardboard, set edge
of this on on template and use as square to get the line
in the exact spot. |
Step 13 Check location of heel unit
by lifting the plate, placing the heel unit on the ski with latch
in open position, then drop the plate so it sets down in the
heel latch. Be sure the resulting configuration matches that
of the photos. If so, check that the paper template didn't get
moved as you worked, then follow drilling and fastening instructions
in steps 9 to 12 above. Done!
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With correctly mounted rear unit, front
edge of latch will be located just forward of the center
of the frame's rear crossbar. This allows space behind the
crossbar for it to move during ski flex. If latch is mounted
too far rearward the platebar can pull out of the catch if
the ski is heavily de-cambered. If it's mounted too far forward
the ski will have a stiff spot while flexing because the
platebar will hit the rear unit.
Note the small concave metal disk visible on the pink
plastic of the touring latch. This covers a screw hole,
and when pushed down with a ski pole tip the binding easily
snaps up and unlatches. If this part is missing you won't
be able to unlatch with a pole tip, and you'll get quite
a bit of snow or water down in the hole, which can corrode
the screw or cause the binding to ice up. If you don't
have the metal disc, at least cover this hole with some
duct tape.
The disk easily pops out of the hole when levered up with
a small pointed object such as an awl. |
*(Drill bits: Ski shops use
special drill bits for drilling skis, usually 4.1 mm for skis
with metal layers, and 3.9 mm for skis without metal. If you
mount a lot of skis, it's a good idea to buy some special drill
bits from an outfit such as slidewright.com,
but it's okay to use the slightly larger 5/32 inch drill bit
as suggested above. If you do so, especially with non-metal skis,
just be careful as you twist the screws in so you don't over-tighten
them and strip the holes, and always use epoxy in the holes.
Pozi screw driver bits are also available from Tognar, and highly
recommended, as are special drill bits for binding screws.)
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