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Thread: Setting a variable edge bevel.
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01-25-2022, 05:36 PM #1
Setting a variable edge bevel.
With most of NA stuck I na high and dry pattern right now, I figured its a good time to discuss edge bevels. I feel al to of people, just go with the stock angles and dont realize how much a difference edge angle can make on a skis performance, even on 115 and wider skis.
Anytime I receive new skis, I like to set a custom edge profile. Over the years I have found that a 3-degree side and 1-degree base bevel is the sweet spot. However, on wider skis those angles can cause the ski to hook a bit. So, taking a cue from some world cup techs, I have started to experiment with varying the edge profiles at the tip, center, and tail sections of the ski.
These are the tools of the trade to do this at home. I own a full set of the Wintersteiger and SVST edge tools. For base bevels I prefer the Wintersteiger adjustable base beveler. For the sides I use both 2 and a 3-degree guides for the sides.
The first step involves using a Sharpie marker to mark the contact points on the skis tip and tail. I then measure the section on each end I want to set the angle. I have found on a 190cm ski I like to do 20cm back from the tip contact point and 24cm’s forward from the tail contact.
I mark these sections with a blue marker on both the base and side edges. I then mark the area left under foot in green.
The bonus of marking the edges with a marker is that it shows you exactly how much material you are removing.
I then start by setting the base bevel for the center section of the ski at .5 once that is done, you are left with the blue areas that then get a 1-degree base bevel.
Next, I set the side bevels. Here I start with the tip and tail sections that each get a 2-degree bevel. Once that is removed, I then set the center section at 3 degrees.
This combination gives you the best performance possible, but it's time consuming. Especially if you take the time to properly harden the edges with a series of diamond stones.
I have found that Wintersteiger has a new Jupiter tunning machine that fully automate this process resulting in a perfect combo every time and it’s well worth having done anytime you get new skis or need a tune up and dont want to spend an hour doing it by hand.
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01-25-2022, 06:14 PM #2
I do something similar, but a little simpler with my Rustler 11’s (my only current ski with significant rocker). Base has a 1.5 degree bevel everywhere except on the inside edges in the underfoot area extending forward/back to where the metal insert ends (which is about where rocker begins); that section of the inside edges is 1 deg. Outside edges underfoot are still 1.5 degree base. Side edges are 2 deg. everywhere, and detuned as necessary.
Firm snow skis all get three deg. sides, 0.5-1.0 base.
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01-25-2022, 07:54 PM #3
I think there’s a step missing at the beginning - grind skis flat with base bevel less than 0.5 degrees. New skis often aren’t flat or have imprecise bevels. For example, my new Mantra 102 came with the center edge bevels at 2 degrees and ends 1 to 1.5 degrees. No wonder they feel odd. I’ll see if I can find a shop with a new Wintersteiger Jupiter machine.
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01-25-2022, 08:36 PM #4
Holy shitballs.
I never thought of such a thing.
But it makes sense.
Thx
PS. Tell more about the Jupiter machine.
Can It do what you do?
Eg. Half degree and 87 degree middle and classic one degree 88 degree tip and tail?
If so. I’ll pay for that shit.Last edited by Core Shot; 01-25-2022 at 09:20 PM.
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01-26-2022, 12:35 AM #5
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01-26-2022, 01:03 AM #6
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01-26-2022, 07:38 AM #7
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01-26-2022, 08:28 AM #8
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01-26-2022, 10:11 AM #9
I think what Stevied is saying is that Gunder is trying to set the base bevel at 0.5 degrees (in some parts), but most skis are going to come out of the wrapper with a higher angle than that. So the only way to actually get that 0.5 degree angle is to first do a base grind.
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01-26-2022, 01:52 PM #10
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01-26-2022, 01:59 PM #11
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01-26-2022, 03:32 PM #12
Correct, nothing new, but its a technique / concept that seems lost / forgotten today. The Jupiter system is pretty slick, its fully automated, and completely takes the tech's skill (or hangover) out of the equation. It's also just now starting to roll out, so not a lot of shops have it yet...
The Jupiter system can do it all, but at any edge combo you want and its more precise.
I've thought about switching to a similar system for the home shop, but I find filing is pretty quick, its all of the switching back and forth to also do the 120, 220, 400 and 600 series diamond files afterwards to work harden the edges that take all of the time. I'm thinking its time to invest in more file guides, so that I have one dedicated to each step.... but thats going to have to come out of next years budget.
It all depends on the skis. On these 117 Kore's they where dead flat, so the .5 bevel worked without having to do a base grind. The marker trick here, is key as it will tell you right away if you are removing material or not. I ordered a Baseman Edge gauge out of curiosity to check the factory stated angles / the results from hand tuning, but it hasn't arrived yet.
Hanging out drinking beers with the guys in the basement of the Rotunda in Portillo, you learn an awful lot!
I think I just need to drink more beers. I find it helps with the shakes. I find that anytime I need to remove metal, whether its sharpening something, or leveling a critical surface Dykem, AKA machinist blue or sharpies work really well to visualize what's happening. Plus it all disappears with a quick spray of denatured alcohol.
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01-26-2022, 03:59 PM #13Registered User
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I need to up my tuning equipment budget. Thanks for writing this up Grant!
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01-26-2022, 08:42 PM #14
I wrote edge bevel instead of what I meant, which was base bevel. So my skis came opposite to what gunder recommends and they don't behave well. Plus the base bevel is already 2 degrees in spots so a grind is necessary to get base bevels to 0.5 degrees in center and 1 degree on ends.
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01-27-2022, 05:52 PM #15indentured servant
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now file/sand/polish the sidewall peeler chatter marks out of the sidewall and you'l be golden
what's orange and looks good on hippies?
fire
rails are for trains
If I had a dollar for every time capitalism was blamed for problems caused by the government I'd be a rich fat film maker in a baseball hat.
www.theguideshut.ca
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01-27-2022, 06:10 PM #16self proclaimed JONG!
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01-27-2022, 06:10 PM #17self proclaimed JONG!
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01-27-2022, 06:13 PM #18
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01-27-2022, 07:43 PM #19
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01-27-2022, 09:08 PM #20
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01-30-2022, 10:45 AM #21
+1 for Stevled's call to get a baseline leveling grind on any ski before getting into tuning angle fetish sessions, we see so many skis coming out of the box or after a bunch of usage so inconsistently base-high, concave, irregularly finished (all all the above), it's maddening. Get those puppies ground to a consistent baseline measurement FIRST before putting the detailed tuning adjustments on 'em. Also pay attention to the transitions of rocker-to-camber-and-back along the length of the ski to set the progressive edge angles in the right spots... some skis are sensitive to this stuff more than others... Totally geeky fun, but it can produce wicked-nice results and get a decent ski to feel awesome with just a bit of work...
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01-30-2022, 01:22 PM #22indentured servant
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what's orange and looks good on hippies?
fire
rails are for trains
If I had a dollar for every time capitalism was blamed for problems caused by the government I'd be a rich fat film maker in a baseball hat.
www.theguideshut.ca
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01-30-2022, 04:32 PM #23
Agreed. I use a Holex straight blade to check base flatness on each ski. That straight edge is very accurate, and is at least as good as my Starrett machine tools, and thats saying something.
BTW if you want a really good shop flash light for this and other things, I recommend a EMISAR D4V2. Its made out of solid titanium and has a magnetic base. Anyways, the proper technique for this is to back light the straight edge with a light.
This is how a brand new ski out of plastic should look, while not perfect on a 115 waist ski, this is pretty damn acceptable.
I'd agree, but not without some modifications. Since I'm actually at home for a change, and its raining at the mountian, figured now is a good time to dig into the sidewall planer issue a bit.
I have both the ski man and the SVST versions.
The SVST is well made and simple, but is severly flawed in its design. It does not have any guides for the cut depth, so all you can do is push the back of the carbide insert along the ski. The problem is since you are using the backside of the cutting edge to scrape the ski, you get a ton of chatter and really inconsistent results. At least it does come with a common sized square carbide insert.
On the other hand, the Ski Man version has two screws for setting the cutting depth and a third for setting the height off of the ski edge. This is essential for consistent results and for using the carbide insert in the correct direction to actually cut.
Problem is, or at least on mine it shipped with a round insert (no idea why you would want a round insert for this). Plus that insert is a size that is typically used on small lathes. I happen to own a life time supply of inserts in the more common larger size, as a lot of the tooling for my Bridgeport mill uses these.
I feel that a square edge insert with slightly rounded corners is best for this application. Here is what I ended up using.
Only problem is these inserts are too large to fit the Ski Man's holder.
So in the Mill it goes. You could do this with any grinder, but I got a mill and its easier to hold the work piece, so I used that.
The larger more common carbide inserts now fit perfectly.
Next, I set the cutting height to be as close to the edge as possible.
I then set the forward and back depth of cut adjustments with the cutter away from the ski, and then slowly using ⅛ turn increments to dial it in to the perfect depth of cut.
I now get very smooth and consistent cuts every time.
Notice the lengths of these shavings. That is what you are going for. Not the short scrapings that you get with the SVST version.
BTW the new Jupiter machines now automatically cut the sidewalls too and better and fast than I can.
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