Results 51 to 75 of 198
Thread: Putting a rocker in my Sumos?
-
02-16-2010, 05:10 AM #51
-
02-16-2010, 09:40 AM #52
I just put some tip rocker in my 190 gold Gotamas. The result was a subtle early rise. I'll download some pictures later. Laid flat with no pressure the tip is only 1/2 cm higher, but the contact point is now 16cm back from the tip, compared to 8cm stock. You can easily see the early rise by squeezing the skis together or when I compare them to a "normal" ski. The rocker is not as much as booner's for sure, but in retrospect I think will be perfect for the gots.
I did the bend in 3 stages, varying the height of the block each time. I also hot waxed the skis each time. I figured this put some heat into the entire length of the ski. I also used an infrared thermometer to measure the heat of the top sheet and an industrial heat gun. I did the work in my garage so the ambient temp was about 55 deg.
Stage 1 - 2 ½” block:
Hot wax skis: Top sheet temp 85 deg.
Heat the skis from the front of the bindings to the tip 125 deg.
Clamp skis down halfway.
Heat skis again to 125 deg.
Clamp fully down.
Sit 24 hours.
Stage 2 - 3” block:
Hot wax skis: Top sheet temp 85 deg.
Heat the skis from the front of the bindings to the tip 130 deg.
Clamp skis down halfway.
Heat skis again to 130 deg.
Clamp fully down.
Sit 24 hours.
Stage 3 - 5” block:
Hot wax skis: Top sheet temp 85 deg.
Heat the skis from the front of the bindings to the tip 150 deg.
Clamp skis down halfway.
Heat skis again to 150 deg.
Clamp fully down.
Sit 24 hours.
Summary: Obviously some skis are going to respond better than others. The goats have a “Dual Layer Sensorwood Core” wrapped with fiber. I don’t know enough to speculate on what types of skis will bend easier than others.
The height of the block makes a difference, I would say bigger is better, but how high is too high?
It takes about 5 min on high heat to heat the top sheets to 150 deg in a 55 deg environment.
I think I could get more rocker with a taller block and higher temp, but I’m going to stop and ski them first. Like I said, I’ll download pictures when I get home.Madness is the exception in individuals but the rule in groups. Friedrich Nietzsche
-
02-16-2010, 02:25 PM #53
Snow7:
For "high heat" on your gun, what does that mean in terms of degrees?
About how far were you holding the gun from the ski?
Did you heat the length of the ski with the gun, or just at the point of the rocker (where it was clamped)
-
02-16-2010, 02:54 PM #54
It is a 1200 watt Grizzly and the website claims 590 C, which is over 1000 degrees F. I can't verify that it gets that hot, but it glows red like a blast furnace inside.
Approx. 4 to 6 inches.
I kept the gun moving in a continuous loop. From the front of the binding (the clamping area) up to the tip, across to the tip of the other ski (they were side by side) and back down to the binding. I was trying to get a uniform heat soak and not develop any local hot spots. I was also very conservative with the heat, as I didn't want to damage the skis. Although, I don't think that heating them up with an industrial heat gun and then bending the beegeezus out of them for 24 hours can be considered normal.Last edited by Snow7; 02-16-2010 at 02:55 PM. Reason: Spelling
Madness is the exception in individuals but the rule in groups. Friedrich Nietzsche
-
02-16-2010, 03:09 PM #55
sweet, thanks Snow7
I have to pick up a gun still, but I'd like to give it a try on my goats.
post some pics when you get a chance
tx
-
02-17-2010, 12:28 AM #56
Subtle early rise in the goats
Early rise on the 190 goats compared to a 190 Fischer Porohete
Same skis, different angle
Ski bondage device. Stage 1 with a 2 1/2" block.
Infrared ThermometerMadness is the exception in individuals but the rule in groups. Friedrich Nietzsche
-
02-17-2010, 01:55 AM #57
Snow7 - good stuff
I have white 06/07 Gotamas. Great skis but I have always thought that they would work even better with a tiny tip rocker/early rise.
I actually storaged them (for the summer) with a small clamp and two ski straps put very tight. That probably flattened the camber just slightly but visually there is no difference.
I have been thinking about selling the Gots (Armada JJ's as current pow skis) but your post will probably make me try that! (Also, getting into the tele quite strongly at the moment, and I guess the rockered 06/07 Gots with NTN's might be the shit...kind of like poor man Obsethed/new rockered Gots! )"Average summit heights are around 1000m to 1200m but on the high glaciers of the main Lyngen Peninsula there are summits over 1400m with Jiehkkevarri being the highest at 1834m above sea level."
-
02-17-2010, 08:40 AM #58Registered User
- Join Date
- Jan 2009
- Location
- Golden, BC
- Posts
- 298
Didier Defago--so hot right now.
-
02-17-2010, 12:41 PM #59
Have anyone tried with K2's? This thread makes me want to try to add just a little bit more rocker to my Obsethed's. I will try to heat and let them cool off clamped.
-
02-17-2010, 12:59 PM #60
Well the process has begun for me.
I have them clamped and working with a 2x4 block and heater gun on high and about 2" from skis.
I'm not sure what temp the skis are getting too, but feels darn hot.
How long have people been heating for?
I started with an 8min cycle, and will probably x3 while they sit clamped for a 24hr period
Here is the current setup...we will see what I get...
Last edited by Bird Blaster; 02-17-2010 at 02:11 PM. Reason: for pics
-
02-17-2010, 04:29 PM #61
I see you put the clamp-down 2X4 about half way between the bindings and the tips. I put it right in front of the bindings. It will be interesting to see which position gets a better result. Lots of experimentation going on.
Madness is the exception in individuals but the rule in groups. Friedrich Nietzsche
-
02-17-2010, 04:34 PM #62
Yeah, tried the setup right in front of the toes first, but thought I wanted to move it a bit more closer to the tip and try to keep as much camber underfoot as possible.
If that doesn't work much, I will move it closer to the toe and aim for more of this years gotama's ELP profile.
After this setup, I'm going to try and bend the tails too
-
02-17-2010, 05:01 PM #63
Keep us informed. I'm very interested to see how the tail rocker works out.
Madness is the exception in individuals but the rule in groups. Friedrich Nietzsche
-
02-18-2010, 10:10 AM #64
Left the skis for about 18hrs. 3 heat cycles of 10mins. Focused more time AT the area to rocker.
Got a pretty subtle rocker out of the setup. When the skis are stacked and decambered it is visible, but on the floor, not so much.
I went back to the rack and added another 2x4 under the tips. I think I will leave them a full 24hrs and complete 4-5 heat cycles.
-
02-18-2010, 10:13 AM #65
-
02-18-2010, 04:25 PM #66
Good job! I think I'll do mine again with the clamp down 2X4 in the same location that you used.
Madness is the exception in individuals but the rule in groups. Friedrich Nietzsche
-
02-18-2010, 04:48 PM #67
I disagree. While there is less sidecut, the running length of the ski is also reduced proportionally, thus the radius is unchanged.
Here's the equation, if anyone cares:
x = change in sidecut from waist to tip (don't forget to divide by 2, both sides of your ski have sidecut)
y = distance from waist location (may or may not be boot center) to widest part of ski / or end of running length
Radius ~= y^2/(2*x). (This approximation holds as long as y >> x.)
Repeat for back half of ski -- many manufacturers seem to use different radii from front to back.Last edited by butterscotch; 02-18-2010 at 05:24 PM.
We heard you in our twilight caves, one hundred fathom deep below, for notes of joy can pierce the waves, that drown each sound of war and woe.
-
02-19-2010, 07:35 AM #68
Pretty aggressive rocker...at a price
So, I continued the rockering process. I wasn't happy with the *minimal* tip rocker I had.
I put another 2x4 under the tips and let it rip. I heated heavy at the rockering point.
I got a great result...but at a price. WRINKLES!!!!! I have two mean wrinkles on each topsheet now.
I think I heated too heavy and it just gave, as soon as that happened I took off the clamps, and whamo...ROCKER. I let it cool, and then after 30mins put it under some cool water to let it set. I then tested the tips for flex. I hand flexed hard on these and they are SOLID. I have some nice camber left under foot too.
I'm pretty pleased at the rocker, but bummed at the wrinkles. I have the tails in the press now. I have one 2x4 under the tails. I don't want as an aggressive rocker as the tips.
I'm sure some think this is completely retarded, but I'm pretty pumped about it.
Last edited by Bird Blaster; 02-19-2010 at 07:56 AM.
-
02-19-2010, 07:47 AM #69
-
02-19-2010, 07:55 AM #70
-
02-19-2010, 08:30 AM #71
Wow! Like Chup said, thanks for the update.
Madness is the exception in individuals but the rule in groups. Friedrich Nietzsche
-
02-19-2010, 05:58 PM #72
Final update:
Worked on a little tail rocker, again not trying to be as aggressive as the tip. I'm pretty pleased with the results (below):
The Gotama Pro:
-
02-20-2010, 02:00 PM #73
It's all fun and games until someone breaks their ski...
I got greedy and tried to replicate Bird Blaster's results. Too much heat and "Snap!". Just flexing the skis by hand finished the break. Doh!!!Madness is the exception in individuals but the rule in groups. Friedrich Nietzsche
-
02-20-2010, 02:19 PM #74Registered User
- Join Date
- Mar 2009
- Location
- Aspen, Colorado
- Posts
- 2,645
-
02-20-2010, 04:13 PM #75
Don't use high heat!! Bad things are gonna happen. You can't force the issue...low heat and moderate force on the ski...anything else is asking for trouble.
If it's green, smoke it...if it's pink, poke it
BUY THESE------> 193 iM 103 - $50 https://www.tetongravity.com/forums/s...d.php?t=179797
Bookmarks