I have had good results with Pens Plus overall, but often find that parts of the barrel dull after sitting for a minute or two. I'm pretty sure this has to do with the density of the wood, and we know that can vary a little even in the same blank. I'm just going to say this is a problem with friction polishes in general because I've had the same results with Aussie Oil.
Of those that use friction polishes...
- How many coats do you typically use?
- Have you had times that it just didn't seem to produce the shine you wanted no matter what you did?
- Does it work better if you pre-treat the wood with walnut oil, or maybe even some other sealant?
How old is your bottle? I've learned, twice now, that this stuff, since it contains shellac, WILL go bad, and when it does, this issue becomes more prevalent until its unavoidable and unfixable. This was kind of what drove me to GluBoost, which for me was a pretty darn big deal, as I really like Pens Plus in a general sense, and am very allergic to CA. But, after losing, well, probably around a whole bottle's worth of the Pens Plus due to the shellac going bad (apparently, the pure filtered walnut oil won't go rancid because it is devoid of proteins, and the Cosmolloid 80H wax is a synthetic material, so it can't be either of those two things), I have decided to stick with GluBoost for now.
When a bottle of Pens Plus is new, it goes on really smooth, crystal clear, and dries well (so long as you don't touch it until its cured, which can actually take a while, more than just the initial drying time on the lathe). Once it starts to go bad though, its a slow onset process in my experience, and the finish just starts behaving worse and worse, exhibiting more of this dulling issue, until every coat goes dull. When that happens, I think its sufficient to say that whatever finish remains in the bottle at that point is bad.
Interestingly, I had similar issues with home made O.B. Shine Juice, which is a shellac based friction polish (1/1/1 ratio of BLO, DNA and Zinsser's Bulls Eye Shellac). This stuff didn't seem to last anywhere as long as Pens Plus, and I often had the problem of it simply not being "shiny" as the name implies. It would go on shiny, then within minutes dull out. I used to think I was doing something wrong, until I realized that the bottles I was making were expiring in about 3 months or thereabouts, and after that the shellac was just bad. Even making a new bottle of the stuff, if I tried the new bottle on a piece I'd already coated a few times with the bad bottle, I could never get it to shine properly.
So, that's one potential issue...shellac gone bad. I think shellac-gone-bad is the key issue with friction polishes in general...and, unless you take GREAT care to preserve your friction polishes and limit the aging and degradation of the shellac in it, sometimes a bottle can go bad in mere months. I think Pens Plus, being a bit more than just a friction polish since it contains the Cosmolloid 80H synthetic wax, has a bit of an edge here, as I've had bottles of this stuff last for over a year before I know for sure they are bad. I think the wax might help preserve the shellac. Most other friction polishes definitely do not last that long, sometimes they last only a few months. This is a shellac problem, as it is a naturally produced substance and will degrade and decay. I've tried to learn exactly why it degrades, but I haven't found any specific scientific explanation. I have found that the more blond/clear shellacs, due to filtration and processing, tend to have a much shorter shelf life than the deep amber garnet stuff, which is usually not used in friction polishes as it would impart a strong color change. Most friction polishes are made with a blond or super blond shellac, so that's part of it.
The other main cause of dulling that I've encountered with Pens Plus, is that it just keeps getting soaked into the wood. If there are more porous parts of the wood, or just parts of the wood that are more able to draw in the finish, then they will often dull.
My solution to this was to buy a bottle of Drs Woodshop Pure Walnut Oil, and finish the blank with that FIRST. In fact, what I would usually do, is for the last few grits (I would usually sand up to 3000 grit, so often from 1200 or 1500 through 3000) I would wet sand with the walnut oil. This would ensure that the wood gets well penetrated with the oil. I would then also friction-polish the oil with a piece of paper towel after cleaning up the blank after the final sanding pass, to jumpstart that polymerization process. Then I would finish with Pens Plus. Once the wood was saturated, the changes of the Pens Plus coats dulling out dropped significantly, unless the shellac in the finish was going bad.
Final thought... I used to apply lots of coats of Pens Plus when I first started. The majority of the recommendations out there were to keep coating with high friction pressure until you had a shiny surface. Thing is, I never quite achieved that pure glass super shiny result by doing that. My success with Pens Plus only came when I started pre-finishing with just the oil, then using only a few coats, 2-3 tops. I have found that pens plus is not the kind of finish you want to "build up", and that so long as the shellac has not gone bad, that sometimes even just one coat will give you a super shiny, highly reflective glass-like coating that rivals a good CA finish.
In one case, I ended up disassembling the pens, turning off the bad finish, and re-finishing with a new bottle, for a batch of pens I was sellign to a client.