Ski Builders Forum

I am trying to stream line my production and I am considering using full Ptex as my tips/tails. My gut feeling is a wood tip/tail is a better construction however that portion of the board/ski only serves to keep the board/ski above the snow. What are your thoughts on using full Ptex tip/tail vs. wood?

CO, ON3P switch this out recently because of breakage (I think this is right). Arguably, whatever the commercial companies are too lazy to do, that's the option to take (IMHO) You might want to look at the underlying costs and compare. There is the technical issue to consider - can you seal the wood? If it's all end grain then you may be onto a winner by simply dipping in a penetrating fluid. Once this has dried, then apply ski wax (watered down, so to speak)

Alt, perhaps capping the tips is an option - depending on your set up.

Hope this helps dude

Rich, did ON3P go to a full Ptex or to wood? I would never leave the wood exposed. Here is what I have been doing and I think most do:
I have a 1-2" setback where for the Ptex on the tip. The problem I am having is milling the core to a 2mm thickness consistently and then the connection between the sidewall Ptex and the tip/tail ptex can split apart during a press and creates a void. I have seen ski builders cut off the core after the effective edge and run Ptex for the full tip/tail. I am wondering if a full ptex tip/tail is a sub par to a full wood tip/tail?

This is what Iggy had to say about it http://www.skibuilders.com/phpBB2/viewt ... &start=105. I suspect they are doing what you have illustrated.

(I think) the straight cut across from the effective edge is sub-par. There are no fibres there to make the joint (only above and below). I suspect it is easily fractured and the glass suffers from fatigue over time. I wonder whether the fracture then begins to acts as a crease.

You've seen the V-shape used by ski manufacturer (eating my own words)? It is sometimes set forward of the effective edge, sometimes behind. I've thought about a simple jigsaw shape in the past ...

I think Idris has suggested that manufacturers have used staples to keep the two piece of ptex together in the past. Perhaps you could extend the idea a little. Use one at the very tip, between the core and spacer - making three in total, but only one staying within the final product.

Is there room for adding sides to the cassette - box the cassette in around the tips? Or creating what you need using allen bolts

What's giving you the problem with the core - any room for a double sided sticky solution?

I put basically a solid square of p-tex (the 2mm thick tip spacer stuff) in my tips/tails (granted they are skis), and have zero issue. I used to cut my core to a shallow point, similar to how K2 does their skis, but I've gotten lazy and get the same results with a straight edge. Saves me a few minutes of cutting.

See the black tip spacer during layup here:

I've always had my doubts about the durability of the straight across full tip spacer.
I made a couple pairs that had full end to end wood cores, but my vacuum press couldn't bend them into the mold.
I had to pre-bend, a total PITA.
My solution was to cut the core back from the running length in a V.




Super simple. and so far (knock on wood) no issues.
3 little dabs of hot glue hold it pretty well.

If I had a pneumatic press I would probably cut my V the other way so the point of the V is nearer the tip.
Straight lines are way easier to cut.

sam

COsurfer wrote:I am trying to stream line my production and I am considering using full Ptex as my tips/tails. My gut feeling is a wood tip/tail is a better construction however that portion of the board/ski only serves to keep the board/ski above the snow. What are your thoughts on using full Ptex tip/tail vs. wood?

I've done it both ways. Honestly from a purist stand point I think a full wood tip is better. Probably less chance of cracking and breaking. But even then I think you'd have to really abuse a board/ski for it to break, unless there is a faulty bond. I've had difficulty too getting the tip down to 2 or 3 mm w/o chipping, tearing, sniping. A better planer would probably help but.... I like Sammers approach using the V. In my next pair I'm using wood tip fill. I have leftover 1/16in ash wood veneer from another project. 2 layers of that equal about 3mm, just right for tip fill. That's one way to keep an all wood core and sidewall if that's what you're aiming for. www.certainlywood.com for thicker veneer.