Oxidized (dry) bases

[Ken_B]

When I stored my daughter’s skis in the spring, I cleaned the bases and used a generic all temperature ski wax. When I checked them last week I noticed that the wax looked dry, actually separated from the base in some areas. I scraped the wax, cleaned the bases using mineral spirits (actually it’s Formby’s Build-up Remover) followed by denatured alcohol, scraped again with a metal scraper, then re-waxed and scraped followed by brushing. She skied approximately 14,000 vertical today and the ski bases are dry/oxidized again. I think the bases are sintered, not extruded (Fischer Koa Sport). I have been doing the same prep on my skis for the past 20 years and can’t figure why it doesn’t work on her skis as well as mine. Thanks for any suggestions.

 

[François Pugh]

Sadly, base burn happens.
Fortunately, most skis can withstand a few base grinds.

 

[Dakine]

I think those skis have extruded bases.
It is tough getting wax to hold for a day on an extruded base.

 

[Plai]

+1 on Fischer Koa have extruded bases. My wife's first pair were these. Had these 3-4 seasons.

Don't know much about waxing, but have tried a generic all temp before and wasn't impressed. It was too soft and wore too quickly.

I now use Hertel Hot Sauce and that is better. It's harder and glides better. Others on this site like more traditional/race oriented waxes.

All the skis are waxed between trips. Don't see much base burn, but my wife probably only does half the vertical of your daughter per day. Our trips usually are 2-3 ski days.

 

[Plai]

+1 on Fischer Koa have extruded bases. My wife's first pair were these. Had these 3-4 seasons.

Don't know much about waxing, but have tried a generic all temp before and wasn't impressed. It was too soft and wore too quickly.

I now use Hertel Hot Sauce and that is better. It's harder and glides better. Others on this site like more traditional/race oriented waxes.

All the skis are waxed between trips. Don't see much base burn, but my wife probably only does half the vertical of your daughter per day. Our trips usually are 2-3 ski days.

Apologies, my wife's Fischers were the Aspire, not Koa. All the references I can find for Koa (80, 84, etc) say sintered base.
Couldn't find the "sport".

 

[cantunamunch]

If you're up for it, try doing 3-5 hot scrape cycles of a REALLY soft wax like Swix CH10 or BP88 or Dominator Base ReNew - then, while the skis are still warm, hit them with a hard wax like Toko Blue or Swix CH5. Make sure you have a good trail of that last wax behind the iron - the topsheets will feel heated - but don't scrape until the skis are well cold, like overnight.

Short of a hot box treatment or finding an ultra-aggressive liquid hard wax, that's about the best results that can be practically achieved.

 

[JohnnyG]

I wonder how Phantom would work on extruded bases?

 

[Wilhelmson]

Hack method, scrape all the wax off, use a sanding block with 120 grit then 220 tip to tail, wire brush, scrape, brush, clean, set base and side edges, hot wax, scrape, brush, wax. Lots of stuff online about xc skis. Tongar has a nice writeup https://www.tognar.com/blog/base-flattening/

 

[Sibhusky]

You really stripped the wax out. Did you brush with a steel brush to see what they looked like before you hit them with mineral spirits?

I'd hit them with a few more cycles of soft wax. It's too late now to determine if that first gray covering was just wax reacting to temperature changes, but unless the bases looked like hell before you stored them, or they were stored in some place that heats up a lot (garden shed in Arizona?), I can't think that it's a problem that requires a grind. Is the grey coming off when you scratch a finger nail across it?

 

[Ken_B]

You really stripped the wax out. Did you brush with a steel brush to see what they looked like before you hit them with mineral spirits?

I'd hit them with a few more cycles of soft wax. It's too late now to determine if that first gray covering was just wax reacting to temperature changes, but unless the bases looked like hell before you stored them, or they were stored in some place that heats up a lot (garden shed in Arizona?), I can't think that it's a problem that requires a grind. Is the grey coming off when you scratch a finger nail across it?

I did not use a steel brush. Maybe I need to get one. I used a hard nylon brush. They looked oxidized before I used mineral spirits. Summer storage was my basement, which never gets above 75 deg. When I scrape with my fingernail nothing really comes off, but the color looks better (black instead of gray). I am beginning to question my thinking that the bases are sintered.