Tonttuwerks Stone Grinding

Touring Refresher Grind
Touring Refresher Grind
Touring Refresher Grind

Over time, a touring ski base can become a mixture of scratches and uneven, concave, or convex ski surface. The intent of this grind is to reasonably clean up this condition and make it easier to glide wax and look at.**

Standard Refresher Grind
Standard Refresher Grind
Standard Refresher Grind

Like a standard stone grind but with fewer passes over stone. Best suited to quickly remove minor base damage to get skis optimally up to speed for important races.**

Only available for well cared-for skis previously ground by Finn Sisu within the last 2 years to ensure flatness.

Stone grind

A three-step process that first involves flattening and removing damaged base material cause by frequent cold wax ironing and constant skiing on cold abrasive Midwestern natural and man-made snows. Ski bases are then ground smooth before a final structure (a pattern of etched lines) is applied that has been researched and glide tested to confirm exceptional glide characteristics.**

Stonegrind w/ Prep
Stone grind w/ Prep
Stone grind w/ Prep

Identical to a standard stone grind except with additional glide wax hardening, a necessity for Upper Midwestern natural and man-made snows. Includes coats of blue and green non-fluorinated glide waxes with the option for either a solid or liquid application.**


*A $10.00 cleaning surcharge will be applied to each pair of skis not thoroughly devoid of kick and/or glide wax.

**Includes brushing, treatment of Rex glide cleaner, and base prep.

Skate Grind Menu


Approximately 10°F and colder — Cold dry abrasive manmade or natural, hard or soft snow.


Approximately 10°F to 25°F — Uni range. Cold dry abrasive manmade or natural, hard or soft snow.


Approximately 25°F to 32°F — Some humidity present in snow.


Approximately 30°F to 35°F — Moister snow, about when you can start making a snowball.


Classic Grind Menu


Approximately 10°F and colder — Manmade or natural snow.


Approximately 10°F to 30°F — Uni range. Manmade or natural snow.


Approximately 25°F to 32°F — Some humidity present in snow.


Approximately 30°F to 35°F — Tracks becoming wet but not saturated.


*Customer can consider hand structuring over any of the above grinds. Additional grinds exist off-menu for narrower ranges. Call/email Tom Novak ([email protected]) or come in for recommendations.

**Note—Some skis that come in for stone grinding have bases that are excessively uneven. This can be due to simple wear or some manufacturers design and choice of core materials that have a high susceptibility to thermal damage (i.e. when waxing skis). Tom strives to get skis flat, but it is not always possible—your ski base has only so much polyethylene.

tom on grinder


Super Sander…

Belt grinders…

Metal Scraping…

Stone grinders…

The evolution of Nordic ski base maintenance.


Wintersteiger Micro 1

In 1993, Finn Sisu purchased the first stone grinding machine dedicated to Nordic ski maintenance in the Upper Midwest—the Austrian built Wintersteiger Micro 1. A state of the art tool to refinish Nordic ski bases, the Micro 1 allowed Nordic skiers to benefit from the same technology that alpine skiers had been benefiting from for years. No longer needing to spend hours in the basement meticulously sanding and/or metal scraping their ski bases, skiers flocked to the original store location on University Ave in Saint Paul, MN to have their ski bases mechanically ground, flattened and structured. Over time, other Upper Midwest ski retailers invested in their own stone grinding machines, contributing to a wealth of grinds that skiers could choose from to make their skis faster.


Wintersteiger Omega RS 150

As ski structures evolved, so too did the capabilities of stone grinding machines. Fast forward to 2015 and Finn Sisu decided to raise the bar for Nordic ski maintenance once again with its purchase of the Wintersteiger Omega RS 150—a semi-automated stone grinding machine with software that rivaled that of some of the most advanced machines out there. One of only five in the United States at the time, the Omega RS 150 was built-to-order, with each subsequent machine produced being an upgrade over the previous. With the more aggressive pink stone on the Micro 1, and a finer grey-brown stone on the new Omega RS 150, the two machines perfectly complemented each other—the Micro 1 flattening and thoroughly removing damaged base material, and the Omega RS 150 polishing and carefully structuring the blanked base.


Wintersteiger Race NC

Around rolls 2020 and, in the midst of other prominent events, Paul Suomi from Vail’s Ski and Snowboard Academy offers Finn Sisu the opportunity to acquire a Wintersteiger Race NC, the finest, fully programmable stone grinding machine Wintersteiger offers. With a total of about a dozen of these machines in existence, and only 3 of those machines residing in the United States, Finn Sisu (with an incredible amount of help from Paul) jumped at the chance to move 1 of those 3 machines to the new store location in Lauderdale, MN. Used almost exclusively by ski manufactures like Salomon, Atomic, and Fischer, and national ski teams like Austria, Germany, Sweden, and Norway, these two-axis CNC (computer numerical control) manual machines produce the most accurate and precise reproducible structures grind techs can dream up. Working in tandem with the Omega RS 150, the Race NC and Omega RS 150 make, arguably, the most capable duo of stone grinding machines anywhere in the United States with the potential to deliver some of the best grinds available to skiers in the Nordic racing community.


Wintersteiger Relationship

Left to right: Paul Suomi, Ahvo Taipale, Tom Novak.

At the end of the day, the relationship between Finn Sisu and Wintersteiger spans nearly three decades in addition to three stone grinding machines. Located in Salt Lake City, UT where they warehouse parts and supplies, Wintersteiger USA’s excellent customer service has been paramount to the closeness of this relationship, with Wintersteiger USA offering real-time tech support alongside their team of regional tech representatives who provide onsite consultations and servicing for their machines.


Wintersteiger Relationship

Brent Johnson, Midwest area Wintersteiger tech rep and our Wintersteiger whisperer, and Tom Novak, our stone grinding master goblin.

If you have any questions, theories, or just want to talk about structure, feel free to contact Tom Novak at Finn Sisu: 651-645-2443 or [email protected]