Aloha back at ya Snow Dragon...Well, at first we were told by V4L to use steel wool. My sister gave up on that when the paint started to come off of her pretty new battery LOL. When that didn't work, she called V4L and they told her to use sand paper or a nail file, as you mentioned. At the time, I actually thought she misunderstood them about the nail file, seemed like "over-kill" to me). So we both tried the sand paper next. I can't remember what grit we used off-hand, but it just wasn't working for us. Thats when I got my husband involved cause I figured it needed some brute "neanderthal" type strength. He did get some of them to work with the sandpaper...but not all. The cool carts were the bigger problem but there was one wow carto too. He didn't go after it lightly tho and suggested to my sister that she get some guy to do it for her. And...Actually, I really do have more strength than "a five year old". Trust me on this, I work with chimps & gorillas on a regular basis (profession: primatologist), so I'm no wimp LOL! It just simply didn't work for me.
So the next call to V4L was from me...and got the same sandpaper and nail file advice (had to apologize to my sister for laughing at her about the nail file). Since we'd "been there, done that", we just sort of gave up on the remaining non-fitters. I had to assume at that point, that we just had some dud cartos. I will go back, however, and check the grit I was using. If its not 400, I'll give that a try per your advice. Maybe I'm using too fine of a grit.
But, I still feel that its not unreasonable to expect that when you order something thru what is considered a well-known, reputable company like V4L, that someone would be checking the batteries etal (especially in the kits) before they go out to customers. If I wanted it to be a DIY venture, I would have bought the cheapo brand at the local smoke shop. Then if it didn't work after I messed with it, I'd figure I got what I paid for...tossed it, and would only be out of a couple of bucks. No big deal. But I went for "quality" instead, and felt the higher price would be worth it because I would start off with good equipment...in working order. And it was apparent from my phone conversation with them, that they knew about the problem for some time. It was not an unknown problem or an isolated incident. Those kits shouldn't have gone out without being re-tooled first. Just my humble opinion.
As far as the guavas and geckos go, they are probably still in the same place you left them. LOTS of geckos here! Mostly running around my house making my 4 boxers go crazy chasing after 'em...but the geckos always outsmart them. Haha!
Thanks for the advice Snowdragon...I will glean our workshop for some 400 grit. Wish me luck.