About gummi stones

[deannatoby]

I have a grey gummi stone by Swix. I have it because it is something you are "supposed" to have. But, I'm always better at using things when I understand how and why they are used. I am having a hard time seeing how this little and soft, basically, little piece of thing makes a difference. Volklgirl, you say to use it on edges between tunings to keep them smooth and deburred. How often? Do you just run it up and down the ski edge once, twice? What? How does that little thing really make that big of a difference? The kids have had ski team practice every day this week. Should I do it every other day, once this week? This gummi stone seems to be more of an afterthought on many tuning info pages, so there isn't as much info. Help me understand my little gummi!

 

[NewEnglandSkier]

I may not be the best person to answer this, as I might be wrong in my use of the stone! But, I generally use mine after each ski day to remove any tiny burrs on the edges. I run it down the edges 1-3 times (varies).
I have one really soft one, which is the one I usually use and then I have another one (a swix one) that is double sided--one side is pink, the other gray and both of those sides seem much harder than my soft one. The soft one seems to do the trick for me, so that is the one that I use.

 

[altagirl]

The gummi stone should be your finishing step when tuning your edges. Then using it in between is just... as needed. If you take like a piece of fabric and run it down the edges of your skis and it feels like it's snagging, use it. If anything's really big or noticeable, break out the real edge tuning gear. So it varies as to how often, just like how often you tune your edges varies.

When I did what tiny bit of ski racing I've done, and when I lived places where we skied a lot of ice - we worked on sharpening edges virtually after every ski day. Moved to Utah and now my skis are lucky to get the edges tuned once a season. It depends both on what kind of surfaces they get used on and how important sharp edges are to you.

 

[volklgirl]

I check my edges every single ski day when I wipe them off before sticking them in the car. If I feel anything rough or "snaggy", that's when I break out the gummi. I use a vigorous scrubbing motion with the gummi flat against the offending edge or a more gentle brushing motion at a 45 degree angle to the edge if there's a "hanging burr" (this is a little, teeny strip of metal where the side and base edges meet that can be caused by hitting rocks and icy chunks or from the action of using a tuning tool on the edges).

When doing a full tune, the gummi is used first to vigorously polish the edges removing the marks and ripples left by the tuning tools, then at the angle to remove any remaining burrs.

The good thing about the gummi is that by using it every day, the edges can be kept in good condition while removing almost no edge material and taking very little time. Also, it's really difficult to do any real damage with a gummi if you get a little over zealous. ;-)

 

[Celestron2000]

Sounds like it could be a good investment...
I'm waxing my skis now, but still a little afraid to mess with my edges.
Sunds like the gummi can be used for maintenance like the wax even if I don't take it any further mysef and take my skis to the shop for any real edge work.

 

[jelenad]

Sounds like it could be a good investment...
I'm waxing my skis now, but still a little afraid to mess with my edges.
Sunds like the gummi can be used for maintenance like the wax even if I don't take it any further mysef and take my skis to the shop for any real edge work.

I am like you... I bought some tuning equipment online and seriously messed up my pair of skis... now they go to the shop for everything other than waxing...

 

[altagirl]

I am like you... I bought some tuning equipment online and seriously messed up my pair of skis... now they go to the shop for everything other than waxing...

It would be virtually impossible to mess up your skis with a gummi stone though...

 

[jelenad]

It would be virtually impossible to mess up your skis with a gummi stone though...

Good to know. I am always afraid to go too agressively on the burrs with my diamond stones...

 

[deannatoby]

What did you do to mess them up? It would be nice to know just so I don't repeat the mistake!

Thanks for all the clarifications on the gummi. I'll gummi the skis tonight, in fact.

 

[altagirl]

What did you do to mess them up? It would be nice to know just so I don't repeat the mistake!

Thanks for all the clarifications on the gummi. I'll gummi the skis tonight, in fact.

I think the main thing would be if you're doing edges and you put a bevel (angle to the edges) on it that you don't like. Or if you're used to having some detuning and don't put that back on there. Some people don't detune at all, but if you're used to it and don't have it, it's going to feel weird.

I guess you could also go a little crazy detuning... but if you pay attention to what you had before and liked, and/or do it a little bit at a time, you should be fine.

I also would not worry about de-burring with a diamond stone, really. I mean, yes, you could go completely crazy and lose some edge, but if you're just doing enough to get the burrs off, I wouldn't sweat it.

 

[jelenad]

What did you do to mess them up? It would be nice to know just so I don't repeat the mistake!

Thanks for all the clarifications on the gummi. I'll gummi the skis tonight, in fact.

Hi there,

As Altagirl guessed, I messed up the edge angle, and took too much structure on the edges with the diamond stone (and not evenly on my edges)... you can imagine that the skis did not feel the same when I tried them after my work on them... I brought them to the shop and they were able to fix the edges, but they recommended that I do not try doing the edges again... maybe it is just me, there are more skilled people who know betterr how to do that. And for $10 edge sharpening, it is not worth the trouble.

I have never detuned my skis... not sure how I should do that...

 

[deannatoby]

During my 1-on-1 tuning tutorial last year we used my skis to learn, and I told the person I had a 1 base/3 side (or .5/3) edge angle. I assumed they had that edge because that's what the kids are supposed to have as racers (here they use a .5/3) and I assumed all other skis did, as well. Now I know having a 2 side is common and better for my level of skiing. For that reason, NOW I'm pretty sure that 3 degrees was wrong, and I DIDN'T have that side edge angle. They were pretty banged up so we started with filing them. Regardless of the side angle they started with, they did end up fine. I've always wondered if we actually filed them completely to a new side angle or if they actually started with a 3 side. I have since bought a 2 degree guide, and I have to call the shop and find out how they tuned mine in November. I know the kids got the race tune, but I don't know what they did with mine.

I tuned the kids skis this week. First time since last season, and I only did it a couple of times last season. I was very nervous! Nobody skied off the side of the mountain, though, so hopefully it all went well.

I don't have any guides for tuning the base edge. That still makes me nervous.

My 9 yo skis (used) were filed so much by the previous racer that the metal is noticeably thin on the edges. Obviously a file-happy parent.

This week I was told I should tune the edges after every second ski session. I'm sure that means diamond stone polishing, not filing. But, with 4 kids I doubt the skis will see that much tuning!

 

[volklgirl]

Have a shop base grind your skis and set your base bevel, then do ALL your work on the side edge only. By continuously messing with the base bevel, all you're really doing is slowly increasing the bevel over time.

A "normal" tune for most recreational skis would be a .75 or 1 base bevel and a 2 side bevel. A majority of us that race or encounter ice or hard pack more than soft snow choose to go with a 3 side bevel for more grip. As far as detuning, it's very rarely done on high end skis anymore as the shape of current skis just don't require that. If you find detuning is a necessity, it suggests that your skis may be too long or too stiff, there's too much rotational force in your technique, or you're skiing in the back seat.

Really, with basic tools and a light hands, it's pretty difficult to seriously mess your edges up. Find a shop you trust with your skis then ask for some guidance - how your skis are currently set up and how to maintain them that way (if you like the way they are now), or what should be changed (if you don't). Most experienced tuning guys are happy to share their knowledge (especially if offered a 6-pack of their favorite brew ).

 

[deannatoby]

Have a shop base grind your skis and set your base bevel, then do ALL your work on the side edge only. By continuously messing with the base bevel, all you're really doing is slowly increasing the bevel over time.

A "normal" tune for most recreational skis would be a .75 or 1 base bevel and a 2 side bevel. A majority of us that race or encounter ice or hard pack more than soft snow choose to go with a 3 side bevel for more grip.

Thanks for the base advice. I'll leave them alone. What do you do when you see mars in the edge that involve the base as well as the side? Do you just sharpen the side and leave the dent in there? My oldest has some pretty handsome dents on her edges already.

They say the .5 base angle here is because of our ice. It's for racers only, but the coaches say it's the "New England" preferred angle, preferred over the 1 base angle. Have you ever used a .5 base angle?

Just moonstoned two skis tonight. I look forward to being quick about the tuning! Right now I'm still fairly slow because I'm wary and careful as a newbie.

 

[volklgirl]

If the edge is rolled over rather than just dinged, I'll use an Arkansas or diamond stone (the Arkansas is softer) on the rolled area only until it's back to level with the rest of the area. If it's just dinged and still flat I leave it alone.

To my knowledge, I've never used a .5 base bevel. However, the base bevel has nothing to do with ice grip, it's only purpose is to allow the ski some wiggle room before hooking up once on edge. The less base bevel you have the more unforgiving and "twitchy" the skis will feel. In general (my theory), mature women prefer the .75 to 1 degree because of both the Q angle and the fact that our ligaments and joints are usually looser than a man's, so our skis need to "swim" a bit without instantly engaging or we'd be constantly catching our edges. Again, that's JMHO! As to the "preferred" angle, I'm guessing you were discussing junior racers?? In racing, they want the skis to hook up NOW, thus the .5 angle..

As an aside, either Rick Snell (Fastman) or MSRT did a study a couple of years ago on base angle, slope angle, and speed which was super enlightening. IIRC, on steeper slopes, the minimal base bevels were faster while on flatter slopes, the larger base bevels were faster. The data was really intriguing.

 

[deannatoby]

Yes, it is most certainly junior racing. Interesting info. I'll google for that study you mentioned. Sounds really interesting. Often I wonder how much of all this information is bonafide, how much is folklore, and how much is opinion. Everybody has their opinion about the best way to wax, and they're sure they're way is most effective. Then there are the little tuning quirks people believe in, etc. Nice to know that somebody actually tried to analyze the base edge difference.

I'm certainly not a racer, so I hope they didn't give me a .5 base edge. I'm still working on stance, weight placement, and getting on edges properly. I was sad to see this morning come. Through yesterday I could say, "I didn't start skiing until 2009," and it sounded like I've been skiing only two years. But, now that it's 2012, it's obvious I've been skiing 3 years and I have less of an excuse for being pitiful!

I watched my oldest (11 yo) ski during team practice this week. I WAS AMAZED!! My little (now big, I guess) Georgia born daughter is carving with her edges and zipping along, looking like a pro IMHO! I can't believe she's related to me!

 

[altagirl]

A "normal" tune for most recreational skis would be a .75 or 1 base bevel and a 2 side bevel. A majority of us that race or encounter ice or hard pack more than soft snow choose to go with a 3 side bevel for more grip. As far as detuning, it's very rarely done on high end skis anymore as the shape of current skis just don't require that. If you find detuning is a necessity, it suggests that your skis may be too long or too stiff, there's too much rotational force in your technique, or you're skiing in the back seat.

I totally agree - haven't done it since going to rockered skis, but essentially, the instructors I've had used to recommend at least some detuning on skis you used mainly for off-piste skiing. It was basically like trying to create rocker before that existed. Now they'd just tell you to go buy rockered skis...

But it is still one of the handful of ways I could think of of messing up your skis by tuning them yourself. Obviously not an issue if you're not doing it.

 

[Kiragirl]

I've been looking online for this type of soft SWIX gummy stone and checking with local ski shops. Stopped in at a shop today to see if they had them in stock...unfortunately no, but they were really cool and gave me two 'used' pieces they had in their shop. psyched.

question: do you wear gloves when tuning to protect your fingers?

 

[Jilly]

WHAT - band aids are a badge of honour!!

 

[Kiragirl]

WHAT - band aids are a badge of honour!!

: )