New skis, bases not quite flat

[SoVT Joey]

You’ll be broke before they can stone grind them enough to kill the ski unless the shop is completely incompetent. The only skis I don’t stone grind right out of the plastic are skis that are over 120. Even my bodacious have a ZAI grind on them.

I wouldn’t even hesitate to grind that ski. In fact I already would have. But I also wouldn’t put it anywhere near a winterstieger and I definitely wouldn’t let anyone belt my base before grinding it.

find a good shop with a good Montana machine and that will change your life. And I’d run a .75 on that base for a bevel.

[SumJongGuy]

Unless you're racing and sharpening your edges constantly with a file (not diamond stone,) once they're done properly, they should be good for a long while. We dealt with this question a lot in the shop and it's EXTREMELY rare for somebody to take their edges to zero. Non racers almost never ever.

Are you looking at the amount of concave they have?? That's how much edge and base that has to be belt sanded down to make them flat. It's a pretty monumental looking task to make those skis perfectly flat

[XXX-er]

find a good shop with a good Montana machine and that will change your life. .

yes a Montana Saphir ^^ was in my experiance life changing even tho the operator was just barely competent enough to press start

[XXX-er]

Edges are ground/beveled before a ski ever comes close to a diamond dressed stone

so how do skis end up concave ?

is that part of a curing process ?

I was told those atomic went concave cuz of the Foam core?

[Bosco]

If the OP is correct, 0.1 mm or 100 microns is roughly .004 inches. This equates to a little over 3 RCH's (red cu%t hairs). Do you really think anyone can notice this?

[XXX-er]

Its ^^ really real IME

[hafjell]

Are you looking at the amount of concave they have?? That's how much edge and base that has to be belt sanded down to make them flat. It's a pretty monumental looking task to make those skis perfectly flat

How much time have you spent working in a shop with good equipment? Not monumental with the right gear.

As for the Wintersteiger / Montana debate, Good Lord, just go with the red machine.

[tuco]

so how do skis end up concave ?

is that part of a curing process ?

I was told those atomic went concave cuz of the Foam core?

Possibly
My theory is in pushing production. Heat speeds cure time. Removing warm skis from mould and the center part of the ski stays warmer longer than the peripheries.
I know the White Room used to put the rocker in Renegades w/ a temperature differential from top/bottom of mould.

[hafjell]

Possibly
My theory is in pushing production. Heat speeds cure time. Removing warm skis from mould and the center part of the ski stays warmer longer than the peripheries.
I know the White Room used to put the rocker in Renegades w/ a temperature differential from top/bottom of mould.

I think this is more than plausible.
Also, I reread the first few responses and agree with them in spirit:
1. If they ski fine, they are fine.
2. If they don't ski fine, "detune" them.
3. If that doesn't work, send them to the shop.
As a shop dork, I would note that a hardware store ruler, held at an indiscernible angle, isn't a perfect start.

[SumJongGuy]

How much time have you spent working in a shop with good equipment? Not monumental with the right gear.

As for the Wintersteiger / Montana debate, Good Lord, just go with the red machine.

I must be looking at the photo wrong because that looks like way more than .1mm If that's all it is then ya, not enough to worry about. Looked more like 1-2mm in the photo. That would be a lot of grinding.

[J. Barron DeJong]

I think this is more than plausible.
Also, I reread the first few responses and agree with them in spirit:
1. If they ski fine, they are fine.
2. If they don't ski fine, "detune" them.
3. If that doesn't work, send them to the shop.
As a shop dork, I would note that a hardware store ruler, held at an indiscernible angle, isn't a perfect start.

I think it was mentioned above, but I’d add to check that base bevel is consistent. Not uncommon to have less near tips and tails from factory.

[J. Barron DeJong]

I must be looking at the photo wrong because that looks like way more than .1mm If that's all it is then ya, not enough to worry about. Looked more like 1-2mm in the photo. That would be a lot of grinding.

if it was 1-2mm I’d be asking for new ones.

[XXX-er]

That ruler the OP was using in the pict looks kind of suspect from the angle we are seeing ?

IME that much concave was evil handing, I forget which I did first the stone grind or tail detuning

but it made a noticable difference

[tuco]

I think it was mentioned above, but I’d add to check that base bevel is consistent. Not uncommon to have less near tips and tails from factory.

Yep.
I'd even do it before skiing them.
Railed skis can ruin a day of skiing!
Ask me how I know!
Also railed skis can be dangerous
Again, ask me how I know!

[Shorty_J]

Possibly
My theory is in pushing production. Heat speeds cure time. Removing warm skis from mould and the center part of the ski stays warmer longer than the peripheries.
I know the White Room used to put the rocker in Renegades w/ a temperature differential from top/bottom of mould.

This sounds plausible but another interesting data point is that when I've seen skis that exhibit subtle errors in pressing its often variable relative to the location on the ski.

I've seen skis that are slightly convex under foot and slightly concave at the widest points.

[RadSkier_]

Anyone telling you to “deal with it” “grind ‘em” or anything like that is a total moron.

You just spent a bunch of cash and received a faulty product. Blizzard will 100% warranty those and send you new ones.

I had the same issue with my Moment Wildcats last season and they sent me new skis that week after I sent them pics (awesome company btw)

You will have to do a lot of work and shorten the skis life in order to get them flat. Take them back and get the warrantied!

[J. Barron DeJong]

Anyone telling you to “deal with it” “grind ‘em” or anything like that is a total moron.

You just spent a bunch of cash and received a faulty product. Blizzard will 100% warranty those and send you new ones.

I had the same issue with my Moment Wildcats last season and they sent me new skis that week after I sent them pics (awesome company btw)

You will have to do a lot of work and shorten the skis life in order to get them flat. Take them back and get the warrantied!

If the base is only out 0.1mm as the OP says it is, and only in the tips and tails, not sure that would be considered a warranty issue.

Pic certainly looks like more, but cameras play tricks when there are spots of bright light.

[Shorty_J]

If the base is only out 0.1mm as the OP says it is, and only in the tips and tails, not sure that would be considered a warranty issue.

Pic certainly looks like more, but cameras play tricks when there are spots of bright light.

Agree with this.

It's not ideal but it is what it is.

For 0.1mm I have personally put a little too much base bevel in the affected area to counteract that and it worked for me without a grind.

YMMV.

[wasatchback]

Wow there’s some bad info here.

Most skis that have rocker will have some sort of concavity in the tips and tails. It’s due to the fact that when these skis are run through the finish machinery there is simply less pressure at the tips and tails due to the rocker.

That being said it will have zero impact on the performance of the ski.

Same thing generally goes for the amount of base bevel in the tip and tail. The fact that there’s rocker will usually mean that there’s less base bevel in the tip and tail. This also isn’t nearly as important as the base bevel under foot. Base bevel of rockered sections of the ski is much less impactful to overall performance than the base bevel of flat or cambered sections of the ski.

Don’t have them ground. There’s zero need to have that done. Zero. Most shops will make them worse, sadly.

I’ve prepped thousands of Blizzards by hand, thousands. For mag tests, retailer demos, etc etc.

Rustler 10 prep would be to add a bit of bevel to the tips and tails by hand, making sure to use some really fine grit Diamond stones to smooth out the structure the file makes in the base edge. Set the side bevel to 2*. (Machine finish can be inconsistent at the end of the skis where there are significant amounts of rocker/side cut). Detune the rockered sections significantly with gummy or sand paper.

[J. Barron DeJong]

Most skis that have rocker will have some sort of concavity in the tips and tails. It’s due to the fact that when these skis are run through the finish machinery there is simply less pressure at the tips and tails due to the rocker.

Are you able to add any detail to this? Seems that if the tips/tails came out of the mold flat, having less pressure applied may mean less material is removed, but wouldn’t make it concave. Maybe the whole length of the base is concave coming out of the mold, and it can be properly flattened over most of the length, but can’t in tips and tails because of less pressure? Or maybe the ski starts pretty flat, but the pressure is applied only near the centerline of of the ski, not near the edges, so at the wider/more flexible tips/tails the center gets ground away more than the edges, making it concave in those areas?

Seems like an issue that could be resolved, but maybe not worth the cost/effort if it’s not really affecting performance.

[RadSkier_]

If the base is only out 0.1mm as the OP says it is, and only in the tips and tails, not sure that would be considered a warranty issue.

Pic certainly looks like more, but cameras play tricks when there are spots of bright light.

But why not at least try and send an email to Blizzard (or the shop you purchased the skis from) and see what they say?

There is obviously an acceptable tolerance to what is acceptable to Blizzard (and other ski companies) on base concavity so it can’t hurt to see if you would perhaps get a proper pair of skis at no extra cost and minimal amounts of time.

After that, if they refuse, then as you can see on this thread you can go a bunch of different ways based on your preferences.

But step one should always be an email back to the manufacturer or ski shop. It’s a no brainer.

[tuco]

Wow there’s some bad info here.

Most skis that have rocker will have some sort of concavity in the tips and tails. It’s due to the fact that when these skis are run through the finish machinery there is simply less pressure at the tips and tails due to the rocker.

That being said it will have zero impact on the performance of the ski.

Same thing generally goes for the amount of base bevel in the tip and tail. The fact that there’s rocker will usually mean that there’s less base bevel in the tip and tail. This also isn’t nearly as important as the base bevel under foot. Base bevel of rockered sections of the ski is much less impactful to overall performance than the base bevel of flat or cambered sections of the ski.

Don’t have them ground. There’s zero need to have that done. Zero. Most shops will make them worse, sadly.

I’ve prepped thousands of Blizzards by hand, thousands. For mag tests, retailer demos, etc etc.

Rustler 10 prep would be to add a bit of bevel to the tips and tails by hand, making sure to use some really fine grit Diamond stones to smooth out the structure the file makes in the base edge. Set the side bevel to 2*. (Machine finish can be inconsistent at the end of the skis where there are significant amounts of rocker/side cut). Detune the rockered sections significantly with gummy or sand paper.

Rocker?
I'm gonna put your post amongst the bad info too. At least your reasoning for a shitty factory tune.
What your describing is a shitty factory tune. Period. Uneven grind.
(which a good tech could take care of on a non automated machine)
Skis as you describe will be hooky. A hooky tune is a shitty tune.
A truly railed ski can be downright unruly. This unruliness will get worse w/ the degree of snow hardness. It's also a dangerous condition. This condition may not go away w/ a rebevel only.
I've had new skis w/ both conditions.
Did you ski every one of those thousands n thousands of pairs you 'prepped", so you knew they needed this "prepping"?
As far as your last paragraph. Yep. Rebevel and refinish edges. If they still ski like shit, grind them. It's actually very highly unlikely a shop w/ put out a shittier tune than factory

[tuco]

Stone grind

This post was in reply to Alpinevibes

[muted reborn]

All this over 0.1mm? Wax them and go.

[wasatchback]

Rocker?
I'm gonna put your post amongst the bad info too. At least your reasoning for a shitty factory tune.
What your describing is a shitty factory tune. Period. Uneven grind.
(which a good tech could take care of on a non automated machine)
Skis as you describe will be hooky. A hooky tune is a shitty tune.
A truly railed ski can be downright unruly. This unruliness will get worse w/ the degree of snow hardness. It's also a dangerous condition. This condition may not go away w/ a rebevel only.
I've had new skis w/ both conditions.
Did you ski every one of those thousands n thousands of pairs you 'prepped", so you knew they needed this "prepping"?
As far as your last paragraph. Yep. Rebevel and refinish edges. If they still ski like shit, grind them. It's actually very highly unlikely a shop w/ put out a shittier tune than factory

The amount of concavity that’s present in virtually all Rustlers does not affect performance in any way shape or form. How do I know? Cause I’ve tested it side by side with one ground completely flat and one just prepped by hand. There as zero discernible difference, in all sorts of conditions. That amount of concavity in the rockered section of a ski does not make it hooky, period. Same ski with camber, maybe but that depends on the ski and it’s construction.

It’s virtually impossible for any ski to come “railed” out of a modern factory. Not enough base bevel, yes… Railed, no.

Just about all factory tunes suck to some degree of suck. A lot of skis need to be ground in order to fix it but plenty can be easily modified by hand in 30 minutes if you know what you’re doing. Smoothing out the bevels at the end of the skis is usually all that needs to be done. I’d so much rather have a ski come with less base bevel, as you can easily add more by hand in 5 minutes. Skis with too much base bevel however need to be ground to be fixed.

And yes I’ve skied on hundreds of pairs of skis I’ve prepped. Test them every year to make sure the tweaking done by hand is correct. Don’t need to ski them all cause once you’ve found what works for each model you can do the exact same to everyone ski as there isn’t that much variance.