Prototype Skis

[Horton]

BONDO!

[Horton]

Anyone have a good photos of the short / fat Goode we have all heard about for the last few years?

[eleeski]

That base looks kind of textured. Like wallboard?

Eric

[skibug]

Looks like a racing stripe to me.  Maybe he had some loose sheet metal and they used some 200 MPH tape at his last pit stop. 

[Horton]

The spliter looks fine.

[DW]

Looks like the wing is set fine, may be a bit tight though.

[Horton]

Nose is kind of high. I know he wants to keep them down on the bump stops.

[HO 410]

http://img.photobucket.com/albums/v357/trauty86/Clipboard01.jpg?t=1206561729

Looks kind of like that chop and widen job done with Parson's 9800. 

[Horton]

I think it is a optical delusion

[eleeski]

Those skis look a lot like the OBrien competitor I sawed in half (just down to the front boot) and wedged a block of wood in the slit to widen the front and filled with glass and bondo. It worked pretty well. Now that I think about it, I haven't seen that ski for a while. And I thought that the only thing missing after the break in was the trampoline. Marcus???

Vacuum bagging sucks. Well actually not enough. My new vacuum pump won't pull enough vacuum to mold skis. I hope the HyBor I'm getting soon isn't a bust also. I could save a lot of money if I would just buy a ski. But I have a fun new double tunnel ski to try this weekend.

Eric

[DaveD]

Eric,

Vacuum is only 14psi.  What kind of pressure do you think you need?  Dave

[eleeski]

I run my molds at about 5 psi pressure. Vacuum bagging should give me lots more pressure on the laminate. But my pump won't even deflate the ski size plastic bag. I think it is sized for model airplane wings.

Since I am too lazy to build another airbag mold I will try squishing some upholstery foam to get a little pressure on the layup. It might be a bit heavier but I am building a prototype ski for the disabled skiers where the binding cage weighs way more than the ski so we'll hopefully get some good feedback despite a couple extra grams of weight.

The Hy-bor is just taunting me. Hopefully soon I can bury it in a cutting edge trick ski. I'm out of my fancy graphite unitdirectional so I'm counting on the Hy-bor.

The double tunnel worked surprisingly well on my test bed slalom. Maybe the double tunnel is solving some of the problems from an overwide ski front. Or maybe it's just getting to ski behind PP classic with a switch and KX- PX10.

Eric

[roda]

Eric,

I used to bag 5' long model sailplane wings (carbon/glass/kevlar), about the same size as a ski.  My pump is designed for some type of vending machine application w/ 100% duty cycle and if I remember correctly I could pull over 20" with it.  I think it cost me around $130 for the pump.  If you are near Orlando you are welcome to borrow it to see if it helps.

What do you have in the bag to allow the vacume to pull evenly?  I used to have a ski rope near all the edges and nylon fabric over & under the part which helped keep air pockets to a minimum.

 -Rod A.

[eleeski]

My pump was supposed to be big enough but I'm not sure what is wrong. It pulls lots of vacuum but the volume is so low that it won't deflate the bag. Maybe I have too much leakage. In any case, I can't build with it being so sensitive to sealing or with such a long evacuation time. The airbags for my trick and slalom molds are quick and easy and effective and generate little waste so I'll stick with them for most of my skis.

San Diego is a long way from Orlando but I appreciate the offer, Rod.

Eric

[DaveD]

Eric,

5 psi isn't that much, strap your shopvac onto that bag. /vanillaforum/js/tinymce/jscripts/tiny_mce/plugins/emotions/images/smiley-smile.gif 

Come on, strap your engineering hat on and do some root cause analysis.  Put your little vacuum on something sealed and make sure it is working properly.  Do you have a vacuum pressure guage?

[eleeski]

5 psi turns into a couple of tons of pressure. And it does squeeze a lot of resin out of the layup. A vacum bag would let me hand squegee some more resin out of the layup - regardless of how much pressure is on the layup. I actually turn down the pressure after it quits dripping - this keeps the mold from flexing and having the ski set up with a flexed mold.

I made a Hy-bor reinforced trick ski today. The MSDS doesn't show any health issues but the stuff is dangerous. It is so stiff that my hands are like pincushions. Fortunately, the fibers are so strong that they are easy to remove. The stuff wets out nicely and after I got careful with the ends it was easy to use (but expensive). I'll see how well it holds up.

Eric