Base Repairs

2nd Sep 2011

It's pretty easy to repair gouges and dings on ski or snowboard bases, but the p-tex repair material you use will determine how long your repairs will last. Soft materials (like drip candles) make fast and easy fixes, but wear quickly. Harder materials (like repair ribbon or techo stix) are applied with an iron or pistol, but make repairs as durable as your original base. And when a gouge exposes steel edge material or fiberglass, use copolymer string because p-tex usually won't bond in these cases.

WHAT IS P-TEX?

P-tex is a tradename for the polyethylene base material used on skis and snowboards. It was originally produced and supplied to ski manufacturers by Inter Montana Sport (IMS) of Switzerland, and, although other companies now produce polyethylene base material under different trade names, just about everyone in the ski and snowboard industry still refers to it as p-tex out of habit.

There are two types of p-tex used on skis and snowboards today...extruded and sintered. 

Extruded p-tex is a low molecular weight polyethylene that is manufactured by heating it to 350 degrees F. and pressure feeding it through a die (or slot) to the desired shape and thickness. It is used as a base material for many recreational skis and snowboards.

Sintered p-tex is made by packing ultra high molecular weight polyethylene powder into a cake that is heated and compressed (sintered) to form a log or billet (see diagram below). A lathe or mill is then used to shave (scive) off a thin layer to the desired thickness.

The advantages of sintered over extruded p-tex are 20-25% higher abrasion and impact resistance, a very low coefficient of friction, and the ability to absorb over 3 times more wax. Accordingly, sintered p-tex is found on the bases of most racing and high performance skis and snowboards.

Electra base is a sintered p-tex to which 15% carbon black and graphite (or a similar metallic substance) have been added to increase electrical and thermal conductivity. The frictional heat that develops (especially at higher speeds) is dissipated better along the entire ski or snowboard base due to this thermal conductivity...it helps reduce the water film that can otherwise build up and create suction and drag. The improved electrical conductivity helps reduce static electricity build-up that attracts and holds dirt and pollutants on the base, also creating more drag.

 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 L., 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 R., 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. 

PROS AND CONS OF BASE REPAIR IRONS AND PISTOLS

Base Repair Pistol 
RP100 (BLI-RP100)

Pros

  • Simple to use
  • Produces durable repairs
  • Fills larger gouges quickly
  • Great for home mechanics repairing multiple skis.
  • Same gun works with 120 or 240 volt.

Cons

  • Limited repair material choices (really only works well with P-tex rods)
  • Switching P-tex colors requires first purging the remaining previous color (you lose about 1/4 of a stick)

Base Repair Iron (MMN-WB1)

Pros

  • Produces durable repairs, especially with P-tex ribbon (SVN-CRIB or SVN-RIBL)
  • Slender tip affects very little of the surrounding base material.
  • Multiple repair material choices (P-tex string, Metal Grip string or P-Tex ribbon)
  • Short learning curve.
  • Operates at a higher temp for more durable bonding.

Cons

  • Takes a bit more practice to use well (our video helps a bit with this) but is not difficult to master.
  • Requires purchase of wide tip for large repairs
  • Not the best choice for performing lots of repairs on multiple skis.

In a nutshell, go with the RP100 if you intend to only use P-tex rods (much better repairs than drip candles) and want a simple, effective method for repairing base gouges.

Choose the MMN-WB1 if you want the option of other repair materials, or if you are doing a limited number of repairs during the season. It is a good choice for folks who enjoy the process of working with a good tool, with a bit of practice the repairs it produces are of very high quality.

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.

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 M. 

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 H., 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. 


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 H., 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 B., 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."