Search found 260 matches

by davide
Mon Apr 12, 2010 4:33 pm
Forum: Ski/Snowboard Design and Layup
Topic: Carbon Fiber?
Replies: 18
Views: 11832

Re: Carbon Fiber?

Glass is not so good in compression which is what I assume the top sheet is under when the ski bends. Is it there just to sandwich the core and protect it? Any advise on carbon and the type, plain, 90 degree or whatever weave? What weight of cloth etc? Thanks for the help. Actually in compression g...
by davide
Wed Apr 07, 2010 12:55 am
Forum: Ski/Snowboard Design and Layup
Topic: How to make fish scales
Replies: 2
Views: 4450

You may attach short and narrow strips cut from an old skin: you will get some grip but they will still glide nicely. Some cross country skis (rental) are like that.
by davide
Wed Apr 07, 2010 12:46 am
Forum: Ski/Snowboard Design and Layup
Topic: Heat and concave bases
Replies: 16
Views: 10695

I have built the same exact ski both ways. With and without heat with the same epoxy. I am sorry that you wasted time and material to find out that hot curing resin should not be cured at room temperature: you could just read the documentation coming with the resin, or prepare short samples of resi...
by davide
Mon Mar 29, 2010 1:25 am
Forum: Ski/Snowboard Design and Layup
Topic: Experimental Ideas
Replies: 18
Views: 11242

I am a bit skeptical about concave base, but skis without edges may be interesting on soft snow: http://www.skibuilders.com/phpBB2/viewtopic.php?t=2306
by davide
Mon Mar 29, 2010 1:21 am
Forum: Ski/Snowboard Design and Layup
Topic: Heat and concave bases
Replies: 16
Views: 10695

Well, the 787 is going to be very expensive and is a more than a year in late... I do not want to convince to use room temperature curing epoxy, if you like hot pressing just do it, but I think you understood my point: if room temperature curing is good enough for gliders, then it is good for skis t...
by davide
Tue Mar 16, 2010 5:47 pm
Forum: Ski/Snowboard Design and Layup
Topic: Heat and concave bases
Replies: 16
Views: 10695

...I think people are experiencing a number of problems with this type of method. One being to hot and the other being to hot to fast. You have allot of different materials all expanding and contracting at different rates. I know, that is why I would suggest to press at room temperature, but I unde...
by davide
Mon Mar 15, 2010 4:11 pm
Forum: Ski/Snowboard Design and Layup
Topic: Heat and concave bases
Replies: 16
Views: 10695

MontuckyMadman wrote:But You have to wait like 14 hours!
Why are you in a hurry? Do you press 20 pairs per day? If not you may wait for a while.
I suppose most of the home skibuilders press a pair per month, or so. Then what about pressing during the night?
by davide
Mon Mar 15, 2010 1:11 am
Forum: Ski/Snowboard Design and Layup
Topic: skis without base and edges
Replies: 4
Views: 4691

skis without base and edges

Recently I had the occasion to join a telemark festival here in Japan: http://www.telemakuri.com/ Pictures can be found here: http://www.skiforum.it/forum/showthread.php?t=40623 It was great fun even if the snow was wet (raining the first day, 15 cm of powder on the second day). During the festival ...
by davide
Mon Mar 15, 2010 12:50 am
Forum: Ski/Snowboard Design and Layup
Topic: Heat and concave bases
Replies: 16
Views: 10695

I guess curing at room temperature would make life easier...
by davide
Sun Jan 10, 2010 9:25 pm
Forum: Ski/Snowboard Design and Layup
Topic: lightest glass that is safe to build with?
Replies: 60
Views: 28532

In the first skis I made (in 2004) I used a very thick plywood core (4 mm at tip and tail and 16 mm in the middle), and I used 400 g/m2 UD plus 300g/m2 biax glass below the core and nothing above the core (or only biax above the core in some other pairs). It is clear that the weight of the glass wil...
by davide
Mon Dec 21, 2009 8:55 pm
Forum: Ski/Snowboard Design and Layup
Topic: Epoxy squeeze out in a vacuum - does it happen
Replies: 12
Views: 8190

Here you can find few pictures about vacuum pressing: http://www.skibuilders.com/cpg/thumbnails.php?album=8 http://www.skibuilders.com/cpg/thumbnails.php?album=6 I used a MDF mold; I used no topsheet, but I put a plastic film above the last glass layer (I will remove the film after curing) and a lay...
by davide
Mon Dec 21, 2009 8:44 pm
Forum: Equipment and Tools (e.g., ski press, core profiler, etc)
Topic: heating the press????
Replies: 12
Views: 8304

SHIF wrote:
thefreshpimpofbigair wrote:...
Read question #1 in the Ski
Builders article:
http://www.skibuilders.com/articles/epoxy.shtml
-S
I guess durability and strength are more important for a glider than for a pair of skis. Epoxy resins for gliders are cured at room temperature, then annealed at 55 degree centigrades...
by davide
Mon Dec 21, 2009 8:29 pm
Forum: Ski/Snowboard Design and Layup
Topic: simmer down now
Replies: 8
Views: 6445

This is the recipe for the dampening system used in some World Cup skis: take a piece of aluminum sheet about 2 mm thick, few cm wide and 10 to 15 cm long and attach it on the first node (some 20 or 30 cm the tip) using a double side tape. That's all.
by davide
Mon Dec 21, 2009 8:17 pm
Forum: Journals: Log Your Ski Building Progress
Topic: Leaf Skis
Replies: 71
Views: 56898

At the first look, I tought the topsheet was made with carbon fiber yarns...

You may buy pre-bent, sanded edges if you want to build many pairs, you will save a lot of time.
by davide
Sat Nov 07, 2009 8:05 pm
Forum: Journals: Log Your Ski Building Progress
Topic: full manufacturing process: from the wood to the snow
Replies: 20
Views: 29597

1) To make the camber, I put a wood block under the mid-ski and weights over tip and tail. Check in my gallery, under Davos. 2) I think steps are not good: mechanical stresses would concentrate there and it may break. At least you should smooth the steps. 3) I made my first pair of plywood skis befo...