
There
are two types of p-tex used on skis and snowboards today...extruded and sintered. The addition of graphite has been shown in tests to reduce friction and increase glide on snow by 20% or more over clear (non-graphite) p-tex bases in cold dry snow (under -13°F or -25°C), and by 15 to 20% more in warmer snow (over 23°F or -5°C) when humidity is 40% or above.
The drawback of Electra bases,
however, is less water repellancy and both impact and abrasion resistance than
that offered by clear sintered p-tex.
Electra-spec, double-sint, and triple-sint bases are a blend of clear sintered,
colored sintered, and/or electra p-tex mixed together and reheated. While the
cosmetic impact of these exotic recipes may be impressive, there is no performance
advantage over standard sintered p-tex bases.
BASE REPAIR MATERIAL FACTS
All base repair materials (ribbon, string, sticks, and candles) are
made of extruded (not sintered) p-tex. Why? You can't heat sintered p-tex to
the melting point without changing it's molecular structure to an extruded form.
Also, black repair material does not contain graphite like a sintered (electra)
base...a dye is used to darken it. Although these materials don't hold wax as
well as sintered material, the amount of surface area they'll probably ever
cover on most bases is too small to matter.
Base repair materials vary in hardness, which affects their
durability when filling gouges on a ski or snowboard base. A soft repair material
wears faster than a hard one, which means that you'll have to refill gouges
more frequently if you use a drip candle instead of p-tex repair ribbon.
Generally it's best to use repair material similar in hardness to your original ski or snowboard base. As you can see on the chart below, the p-tex ribbon is similar in hardness to a sintered base...while the repair string is more similar in hardness to an extruded base.
There are, of course, exceptions
to the rule. When filling gouges alongside a steel edge, for example, we prefer
copolymer, because...unlike other materials...it can bond to steel. Softer repair
materials also bond more easily in shallow scratches on ski or snowboard bases...so
we prefer to melt in soft material with a repair iron for these, and then switch
to harder material for more durable repairs in medium and deep gouges.
A soft p-tex material, like a drip repair candle, is fast and easy to apply.
This can be handy for travel or ‘on-the-spot’ repairs, but it will wear much
quicker than surrounding base material. This might be okay for very shallow
scratches, but in deeper gouges can become an ongoing maintenance nightmare.
Harder p-tex material, such as our repair ribbon, string or techo stix, take a little more time to apply...but last much longer. They won’t wear or ‘dish-out’ in gouges as fast over time. Some folks have noted that these materials don’t ‘flow’ into gouges like drip repair candles do. This is because they are denser and more durable, so don’t be discouraged by appearances.
If the gouge exposes any steel edge material or fiberglass (as in a core shot), first melt in copolymer repair material (made of polyethylene and a rubber-like ingredient), since it will bond to these materials. Then melt p-tex repair material atop the copolymer to fill the gouge, since p-tex will bond to copolymer but not steel or fiberglass.
Base Repairs- Drip, Melt or Epoxy?
Base gouges are repaired using different techniques. These include dripping in soft molten repair material from a drip repair candle (good for small or surface scratches, or temporary repairs if you're on the road), melting in harder repair material using a base repair iron or pistol (good for deeper gouges), or gluing in a p-tex patch if the damaged area is even larger or more problematic.
DRIP REPAIR INFO &
TIPS
After initially lighting a drip candle with a match, lighter or candle, hold
it close to the base to avoid black carbon build-up...1/4" above the base with
the candle held at about a 30 degree angle to the base will result in a very
hot, low blue flame. This is hotter than a yellow flame and will more effectively
consume the carbon with its higher heat.
When using a short p-tex repair candle, blow out the flame before it gets short enough to burn your fingers and stick it to the end of another drip candle before it cools...it'll bond to it as it hardens.
I saw off the end of a busted
aluminum ski pole (about six inches in length), cut a few inch long slots in
the hollow end, and bend them in just slightly so it will grip a p-tex candle.
You can use this gizmo to save your fingers from burns when your p-tex sticks
start getting short.
-Michael Roca, Springerville, AZ
If you're filling a big deep gouge on your base using a drip candle, fill it
only partway initially. After this material has cooled, drip in more repair
material until it's a little higher than the rest of the base. When this cools,
work it down flush using a steel scraper.
-Casey Hennekens, Marlboro, NY
MELT-IN REPAIRS
Check out the video below to see how to use the base repair Iron with string and finish with the surform and steel scraper...
To apply harder (and more durable) repair materials...such as repair ribbon,
string or techo stix...use a base repair iron or pistol. Hold the repair material
over the gouge, and use the tip of the iron to press and melt it directly into
the gouge. With a repair pistol, gently squeeze the trigger to get therepair
material (techo stix) to flow out of the tip and directly into the gouge.
Gradually melt in repair material (in successive layers if necessary...especially for very deep or large gouges) until you’ve overfilled the gouge. Let the material cool a few minutes. To remove excess, a regular steel scraper will usually not be sharp enough...its dull edge will tend to grab and yank these harder repair materials out of the gouge. You need a sharper cutting tool for this operation. We recommend using the Versaplane to initially remove excess material...it is very sharp and cuts very cleanly.
Once you’ve shaved away most of the excess, you should then be able to use a steel scraper of base flattener tool to take off the remaining material until the repaired area is flush with the rest of the base. Then, to make new repairs visibly blend in better with the surrounding material, you can lightly restructure the base with a tool such as the brass riller bar or SkiVisions base flattener...altho if the repair is small, this might be more effort than it’s worth.
You can substitute a soldering
pencil or wood-burning iron to melt in p-tex repair material, but be very aware
that they can get way too hot for safe p-tex repairs (over 900F vs. 500F for
a base repair iron). For greater safety, plug and unplug it regularly to keep
high temperatures down and thus help avoid dangerous wax fumes...especially
if you use fluorocarbon wax on your bases. Good ventilation and a respirator
should also be used for safety.
-D. Salera, Mulino, OR
I suggest that P-tex repair material can be carefully melted into gouges with
a propane torch, which eliminates worry about carbon build-up or a furiously
dripping repair candle. Merely extinguish the drip candle each time you move
to a new scratch.
-Pat Hinz, Bozeman, MT
Editor's note:
Thanks for the "hot" tip, Pat; While we agree that some folks can safely make
base repairs with a propane torch, we personally don't like 'em for a coupla
reasons.
First, we're klutzes with open flames (especially torches)...and, invariably,
usually manage to accidentally burn something other than what we're trying to
fix (such as the base material where it's undamaged, fingers or thumbs, benchtops,
or even our entire workshop!). It requires total concentration and undivided
attention...two qualities we're sadly lacking.
Second, torches burn so hot they can potentially transform fluorinated waxes
(including the old residue on a ski or snowboard base) into a deadly gas. As
noted above, it's all too easy for the torch flame to accidentally wander if
you're not careful, and this remote but dangerous possibility scares us.
Third, if the torch flame accidentally skims the base surface, it can oxidize
the material so it won't absorb wax easily, or...if the heat is sufficient...
can physically transform the structural makeup of that nice tough sintered base
material into extruded material (such as found on cheap equipment)...so why
risk it?
Last of all, you can get the same carbon-free repair results by lighting the
candle end with a match, and holding it close (1/4" or so) above the base (or
a steel scraper when between gouges) to keep a blue (not yellow) flame burning.
The candle will drip slowly and steadily into gouges with little carbon buildup.
If
you use a propane torch to apply p-tex to your base, I suggest you nail an empty
coffee can to your workbench. This way you have a stable container to hold the
torch when lighting or letting it cool off.
-Jeremiah Lumbaca, Phoenicia, NY
Here's a tip for folks who use a propane torch for doing p-tex
repairs. Camping stores sell plastic stand-up bases for propane bottles (designed
to be used with propane stoves or lanterns) which will pay for themselves the
first time a propane bottle doesn't get knocked over. Flaming hair may be trendy,
but very annoying!
-Michael Roca, Springerville, AZ
Repairing Core Shots and Gouges Along Steel Edges
Check this video on how to repair alnong the edge and replace a section of steel edge.
If
the gouge exposes any steel edge material or fiberglass (as in a core shot),
first melt in copolymer repair material (made of polyethylene and a rubber-like
ingredient), since it will bond to these materials. Then melt p-tex repair material
atop the copolymer to fill the gouge, since p-tex will bond to copolymer but
not steel or fiberglass.
I use a ceramic tile to help press p-tex or copolymer repair material into gouges.
It helps ‘set’ the p-tex in place, draws off heat and nothing sticks to it.
<Fiberjoe1@aol.com>
After filling a
deep gouge using a p-tex repair pistol, I use a piece of 1/4” bakelite (a thermal
insulator) and press it over the still molten repair material. I use a spring
clamp to keep pressure applied to the bakelite while molten p-tex keeps flowing
into the gouge as it cools.
With large gouges, especially next to steel edges, I sometimes widen the gouge
on the side toward the center of the ski or snowboard to create a keystone effect...this
can help mechanically restrain the repair from pulling out.
-Bruce Murdock
Since I’m skiing on a college students budget, I made an
inexpensive p-tex roller for pressing p-tex repair material into gouges. I bought
a metal scraper and bent it around a can of tomato soup to make a rounded "rocker"
shape to press the p-tex in. I’ve had this homemade tool for over 2 seasons
now and, for a cheap tool, it works well...plus I got to eat the soup, too!
-Dan Hurwit, Schenectady, NY
Here
are a few tricks for handling particularly deep base gouges that go clear down
to fiberglass or are alongside steel edges:
1) Melt repair material into the gouge, then immediately take your true bar
and press it down on top of the repair until the material cools. The true bar
acts as a large flat heat sink and helps keep the repair material from pulling
away from the steel edge during the cooling process.
2) If there is a lot of steel edge exposed, take a little bit of epoxy and spread
a thin layer over the exposed metal. Then immediately lay a thin Kleenex-like
piece of non-woven dacron fabric such as Remay or Pellon (available at a fabric
store). Use a piece just a little smaller than the exposed steel or aluminum
and place it on the layer of epoxy. Heat the area with a blow dryer or heat
gun until the epoxy flows into the fabric. Allow the epoxy to gel (not rock
hard, but thick enough so it can no longer run or flow by itself). Trim off
any excess material that might be in the hole, then use the "melt and press"
repair method described above. The results are usually excellent.
3) If fiberglass is exposed beneath the base, spread a thin layer of epoxy over
it. Let the epoxy gel, then fill the gouge with p-tex material. This should
create a strong bond.
Other Related Tips
REPAIR A BASE "BUBBLE"
A careless moment with an overzealous wax iron damaged my p-tex base, causing
a section about the size of a dime to bubble up and separate from the wood core.
What steps can I take to fix it?
-Larry Mah, mahbh@cunyvm.edu
Here's three steps we'd recommend, Larry...
1) First, drill a small hole or make a small slit with a razor knife through
the p-tex in the center of the bubble. Inject a little epoxy inside the bubble
using an epoxy syringe, then use some c-clamps and steel scrapers as plates
to press out the bubble and let the epoxy dry.
2) If this fails, you can cut out the bubble with a razor knife, apply a very
thin layer of epoxy to cover the exposed fiberglass, let it dry and fill in
the area with p-tex repair material using a repair iron or pistol. This will
sometimes work for small bubbles.
3) For larger bubbles, repeat step 2 (above), but glue in a p-tex patch instead
of melting in repair material. After epoxying the patch in place, use some c-clamps
and steel scrapers to secure it until the epoxy dries.
SIGN HERE
To personalize your gear (as well as discourage theft) use a contrasting-color
repair material to fill base gouges...your bases will always have their own
unique "signature".
BASE BONDO
To repair those base edge gouges and core shots without copolymer,
make ski 'bondo'. I use a Surform file which makes p-tex 'cheese' gratings from
previous repairs. Mix these with two-part epoxy to a bondo-like consistency,
and tamp it into the gouge about 1/16" below the original base level. Let dry
before topping the repair off with an iron and p-tex material (or drip candle),
but be sure the bondo gets a little warmed up in the process. This way, the
bondo sticks to the core or steel edge, and the top layer of p-tex sticks to
the bondo for a serviceable & long-lasting patch (albeit not always the
prettiest) that absorbs wax well.
To check progress of base and/or side edge bevelling, mark all edge surfaces
with a black felt-tip marker and watch to see how much is left after every few
passes.
-Jay Hyland, Eaton Mt. Ski Patrol, Shawmut, ME
CARPET TRICK
A good method of catching wax and p-tex drippings, scrapings, and filings
is to place a piece of carpeting under the entire lenth of your skis on the
workbench (make sure it's not flammable!). This works especially well in motel
rooms. It can be shaken clean and ready for next use. (Note: Beware of letting
melted p-tex drip on the carpet. It can either ignite or burn right through
it!)
-Gary Baud, Wakefield, RI
BASE PATCH FAILURE
This cat is up a tree again! I patched a base gouge about 1-inch square on the
bottom of my Volkl F4’s. There was exposed metal underneath. I mixed up some
good slow-curing epoxy to adhere the fresh p-tex patch material to a clean dry
metal surface...but not so much that it oozed up around the edges when I carefully
clamped the patch in place. This was done in the garage, but with a heat lamp
about 2’ away, then I set the ski inside the house overnight.
The next evening I undid the
clamps, filled in any seams around the patch with copolymer and topped off with
p-tex repair material. It didn’t look too bad, and was very flat after sanding
and planing the area with the SkiVisions Base Flattener I bought from you recently.
I finished up applying a hot wax. My iron was the right temperature and my passes
were at a decent speed. After two or three passes with the iron, however, the
patch came loose.
Do you think I did something wrong (wrong epoxy, etc.)?
-Bob
Bob- From what you’ve described, it sounds like heat from your wax iron
may have caused the metal underneath to warm up enough to soften the epoxy,
which led to the patch coming off. Most skis have fiberglass under the p-tex
instead, which doesn’t heat up as much as metal, and therefore avoids this problem.
One suggestion is to roughen up the metal surface (make scratches on it with
a steel needle pick (see page 48 in our catalog) or ice pick. This roughness
can help provide a better anchor when you epoxy the patch back in.
Another thought...did you place a metal scraper or thin steel plate over the
patch to apply even pressure over the whole patch before clamping it down? This
could help provide better adhesion.
When you hot wax in the future, go lightly over this area so less heat is absorbed
by the metal layer under the ski base. You could likewise rub on wax after you
heat the end of the wax bar against your hot iron, then carefully heat it into
the p-tex with the iron, or rub it in gently with a hand cork. As a last resort,
avoid hot wax altogether here...instead, apply a liquid or paste wax such as
Swix F4, Toko Express, or Holmenkol Liquid wax in this area, and only hot wax
around it and the rest of the ski base.
WARM 'EM UP
If your workbench is in an ice-cold room like mine (the garage), keep
your boards inside at a warm room temperature until you're ready to work on
'em. Semi-warm bases are easier to repair/file/wax than cold ones. Work on one
ski at a time, keeping its mate inside. Another alternative is to make a quick
pass with a hair dryer to warm bases.
FIXING
BASE DIMPLES
When mounting my bindings, I accidentally drilled one binding screw hole a little
too deep. The drill bit didn’t go all the way through the p-tex base of the
ski, but did raise a pinhead-size protrusion (dimple) in my base. What should
I do to fix this?
-Robert Floro, Sydney, Australia
Well first off, Robert, rest easy...this is not an especially uncommon occurrence,
even in ski shops. As long as the surface of the p-tex base is unbroken, you
can simply push this dimple back in. Crude as it sounds, we just hold the rounded
head of a ball peen hammer against the dimple, then gently tap the opposite
end of this ball peen head with another hammer until the dimple is pushed back
in.
If you had drilled all the way through, you could repair it by injecting a tiny
bead of epoxy glue just inside the bottom of the hole, then top this off with
some metal-grip repair material. Afterwards, you can restructure the base if
appearances are important and you want everything to blend together...altho
the surface area affected by these mishaps is usually so small that restructuring
probably won’t affect performance.
BASE BURNOUT
The immense friction resulting from race skis tracking mega-force turns at very
high speeds on hard snow in World Cup downhill courses can literally burn away
ski base material underfoot in only one or two runs.
EXTREME REPAIRS
We talked with extreme skier Kristen Ulmer recently and asked her if she
had a special tuning tip she'd like to share with us. Here's what she shared
with us...
"How you react to unexpected rock hazards when skiing extreme terrain can
make a big difference in how well you and your equipment survive the encounter.
It's usually better to ski straight over unavoidable rocks rather than trying
to check your speed or turn once you're atop them. Turning exposes the skier
to a greater chance of catching an edge and falling...about the least desirable
situation in extreme terrain...and catching an edge when your ski is sideways
to rocks greatly increases the chance of ripping out a steel edge or doing serious
structural damage. Better to go straight over those rocks so gouges run down
the length of the ski rather than across it...even if deep, these long gouges
can usually be repaired more easily and cause much less structural damage."