Saturday, February 20, 2016

Using Penetrol on MINI Cooper black trim

Although owners of the different generations of MINIs may engage in some friendly picking with each other about which generation is best, they all have one thing in common. That is having to deal with maintenance of the black trim pieces. Of course, black trim is not limited to MINIs and is a problem for a lot of people as you can tell by all the products on the market designed to keep it looking black and combatting the inevitable fading that seems to occur.

Thanks to Paul Penny and some folks over at Motoring Alliance, I stumbled upon a new method that looks to the home improvement market for a solution. The product in question is called Penetrol. It is a paint additive that is primarily designed to eliminate brush marks. I did note that the container says it can also be used to restore fiberglass. Penetrol can be purchased at places like Home Depot or Lowe's.

I went into this with some hesitancy. However, all of the people who reported using it seem to swear by it and I find them to be good sources of tips and tricks for care of a MINI. Although I do want to know who thought, "let's try rubbing this paint additive on the black trim to see how it works" - must have been like the first person to break open an oyster to see if they could eat what was inside.

In terms of what I was facing, I had the typical fading going on with my MINI. I'm not completely OCD when it comes to keeping my MINI clean and it is a daily driver. However, I do try to keep it waxed on a regular basis and do what I can to maintain its appearance. For the trim, I did have some glue from the tape I used for the last wax job as well as some of the wax that had dried on the black trim (not coloring in the lines). This was along with the normal fading that has occurred since my last attempt to clean and service the black trim.


To get started, I went over the trim with a Magic Eraser. This is my own little spin on prepping the trim and I've done it with past maintenance efforts. The Magic Eraser does a pretty good job of cleaning off residue and the surface in general, though it does leave a lot of dust. The next step was to go over the trim with Acetone (again, purchased from the local home improvement store). I actually went over it all twice. The first time I used a wash cloth to get a little bit of abrasion to try to attack the dried on wax and other mess that didn't come off with the Magic Eraser. This did a decent job, but there was still some left over streaks and surface dust. I went back over everything with the Acetone a second time using a microfiber cloth. This got things prepped pretty good, though I could still see some wax in a couple places.


The next step was to apply the Penetrol. For this, I used a 2-inch foam paintbrush (can you say home improvement store again?). This gave me good control along the seams next to the paint. Basically I was painting the Penetrol onto the black trim. I just went slow, loading up the brush with fresh Penetrol every so often and then brushing it on. I did notice a couple times that the Penetrol started to get a little bit tacky, so I recommend not trying to do too much at one time. I would do a couple feet worth, then go back with a paper towel - the blue shop towel kind you get from an auto parts store as they are extra absorbent. I'd wipe everything down with a light touch just to get any excess Penetrol off and smooth things down. If any gets on the paint, get it off as well as soon as possible.


I just took my time doing this until I had hit all of the black trim. The good thing is it did not require much elbow grease. I'm not sure how long the Penetrol takes to fully dry and cure. I'd guess a good 24 hours. I'm fortunate in having a garage available where my MINI can sit overnight if it does take that long.

On appearance, I'd say the trim looks pretty good. Nice and black again without being too shiny - basically back to a stock condition. Getting the trim black is really only part of the equation though. Many products out there can get the trim to this point. Perhaps the bigger challenge is durability. Most everything I've tried in the past lasts no longer than about a month before you can tell it has started to wear off.


All of the reviews of Penetrol used for this purpose indicate the application should last for about a year. The only thing is I may have to do a second application. Lucky for me it is only February and I usually do a semi-annual wax later in the spring, so I can re-assess it at that point and apply the second coat if necessary as part of my spring detail.

As I mentioned, I was hesitant about trying this solution. If you go for it, you'll find the Penetrol is a serious chemical. However, being patient with the application and taking the time for proper surface prep seems to have yielded one of the best black trim clean-ups I've had in eight years of MINI ownership.