New skins don't stick

Kamtron, your comment about the bases is very interesting. As mentioned, my skis are new. I had to lightly sand one of them with 600 grit sandpaper under foot which left it smoother than the other ski. I intended to get the base ground at a ski shop or to roughen it with coarse sandpaper so both skis would have similar base preps, but I haven't done it yet. I think the ski that had less problem with the skin was the one I sanded. As I also mentioned, I have not waxed them. Maybe a smoother base is better for skin adhesion.

Kamtron, what is the base prep on your skis or snowboard?
 

If you sanded them, you removed all base structure, which you will want for smooth glide in the snow. I don't see that affecting the skins unless maybe there was base dust that got into the glue and f'd it up. Do you think that happened? Why did you sand anyway?

I would actually take a couple of light passes with a coarse sandpaper to add some structure. Some people use a brillo pad. That works too. Then wax with whatever wax you want and scrape and brush. If you're unclear what to do for waxing, maybe just take them to a shop after you add the base structure and tell them to give you a standard wax. You're not nordic racing, so you don't need to worry too much about the details of the process. There's good info on the web.

Honestly, if your skins stick well when you're home but not in the field, it's kind of mysterious. They should stick unless something weird on your base (chemical?) is repelling them.

I sanded one ski before I cut the skins. I was concerned I might contaminate the skins with dust, so I cleaned both ski bases full length with damp and dry cloths a couple of times. I didn't reuse any cloth. I didn't use detergent because I thought getting all detergent off might be difficult and because sanding shouldn't apply any oils or wax to the surface. I'm not absolutely sure I kept dust from contaminating the skins, but I'm very confident I had a clean surface when I trimmed the skins to width.

The first reason I suspect a smooth base might yield better skin adhesion is my field experience that day. I noticed that the ski with the factory base was the problematic one. I didn't and don't want to jump to the conclusion that a smooth base is the reason for better adhesion. I would think BD and other manufacturers would test what yields better adhesion and they would reply accordingly to my email. If they know what helps with better adhesion, they should put it in their product guide. I have never seen anything like this except to keep the skins clean.

Another reason that I'm guessing a smooth surface improves skin adhesion is that a smooth surface will have fewer and smaller surface pores where water could be trapped when applying the skins. After attaching the tail clip, I press the skin against the ski from tip to tail a few times. I'm sure everyone does this. I suspect pressing the skin onto the ski might help expel water especially if the surface is smooth. The surface could be smooth due to sanding or waxing.

I've always assumed the surface roughness on the bases was there to improve adhesion of wax and wax improves glide as you said. Am I wrong?

You asked why I sanded one ski. I feared some perceptive person would ask this question. From this day on, I will be forced to wear a brown paper bag over my head in shame. I put Quiver Killer inserts in these new skis as I have done to 3 other pairs of skis. I've always followed the instructions to the letter. This time I did not put a stop on the tapping bit when I was cutting the threads. I thought it would be good to cut the threads as deep as possible and that the material below the bottom of the hole would be stiff enough to stop the tapping bit. This last assumption was wrong. Fortunately, I turned the ski over after tapping 5 holes and found dimples on the base at each one. I pressed the dimples in as much as I could, epoxied the inserts, and a couple days later I sanded the dimples with a wide piece of sandpaper and a block of wood wider than the ski. Now, where is that brown paper bag.
 

mBraun wrote: You asked why I sanded one ski. I feared some perceptive person would ask this question. From this day on, I will be forced to wear a brown paper bag over my head in shame. I put Quiver Killer inserts in these new skis as I have done to 3 other pairs of skis. I've always followed the instructions to the letter. This time I did not put a stop on the tapping bit when I was cutting the threads. I thought it would be good to cut the threads as deep as possible and that the material below the bottom of the hole would be stiff enough to stop the tapping bit. This last assumption was wrong. Fortunately, I turned the ski over after tapping 5 holes and found dimples on the base at each one. I pressed the dimples in as much as I could, epoxied the inserts, and a couple days later I sanded the dimples with a wide piece of sandpaper and a block of wood wider than the ski. Now, where is that brown paper bag.
 

You're cracking me up. I wouldn't worry about it too much! Try touring a second time and see if the problem goes away.

I agree with Kamtron, I don't think you did anything wrong - either a bad batch, or a bad day (and could be all good going forward, fingers crossed).
FWIW, some skin manufacturers specifically state the tail clip is to simply keep the skin in place, and the tension shouldn't be very high, i.e. the glue should keep it on the bases. In fact, too much tension would pull it off them due to camber - overanalyzing it, I'm sure, but the point being, the tail clip should not be the Hail Mary here. Good luck, man!

I have edited this final comment for others whose skins aren't sticking. The source of their problem might be the same as mine, but there are other possible causes too.

I used my skins a couple more times and they stuck well. I concluded that, in my case, the problem was moisture or water.

I'm still using mesh skin savers because the skins are so difficult to separate without them. I think mesh skin savers exacerbate the problem by providing capillaries for water transport. Inevitably, one way or another, a little snow gets on the adhesive and, as always, I brush it off the best I can. I used to put my skins in my jacket during the descent. Now I put them in my pack because, on one or more transitions, I had observed water droplets all over the adhesive when I separated them. In my pack, the skins stay cold and any snow that I have failed to remove, doesn't melt and doesn't spread. Skiers who don't use skin savers might prefer to put them in their jacket during the descent, because moisture cannot get between the adhesive surfaces and the warm adhesive will work better.

I adjusted the tail clip so it stays clipped and the skins are tight but not too tight.