MintLP Protractor Issue. Anyone else?

I went to use my MintLP Protractor last week to do a re-check of Arm, cause I had dis-mounted the Arm.

Last time I used it, was when I first recieved it, over a good year ago, maybe closer to two years.

What I have noticed with mine, that it was once a frosted transluscent clear overlay over a sheet of glass mirror has now changed.

Now I notice, that clear frosted color of the overlay has turned a dirty brown stained color. Anyone else have this happen?

Whether any other detrimental effects have occured, I am unsure, but this Protractor was always kept wrapped in its protective Plastic Bag, in its Cardboard Shipping Box, it shouldn't have turned a brown color, expecially not for what this protractor cost.

I'm thinking of emailing Yip, and asking why this happened, and what can be done about it? Mark

I've had mine for a year and it looks exactly the same as it did when I first saw it. I store it the same way you do.
Mine is also almost 2 years old and stored in the same fashion. It appears the same as the day I received it from Yip. I would contact him to discuss the change.
Well, you got me curious so I just looked at mine and guess what? It is also that dirty brown color. Now I don't really remember what it looked like new but I purchased mine about the same time- 1-1/2 to 2 years ago. I wonder if a bad batch went out? I have to say though, even with the brownish color I have no problem seeing the critical points.
I just checked mine also, it's 21 months old and still like new. Did either one of you clean it with anything? I store mine in it's plastic sleave and in the box, and have used it several times. Good luck to all.
Mine's like brand new still as well, about 20 months old.

I have not cleaned mine yet. You bring up a good point though. I thought I remember Yip having specific directions about cleaning it, but I can't remember what it was.
Yes, Yip made mention that if the Protractor needed cleaning, it should be wiped with Iso Alcohol, nothing else.

And I did with mine once, due to seeing slight scratching of the overlay, caused by the Stylus at the Null Grids.
Mine appears to be the same as the day I got it.
Am on my 3rd Mint LP in 3 years and apart from some scratch marks at the null points caused by the stylus , I have observed no other wear and tear and certainly no brown marks or discolouration of the kind Mark found. I live in a relatively more inhospitable climate in terms of heat and humidity etc
Happy listening
I'll send Yip an email and ask him for input. He really is very friendly and helpful and approachable. I don't know why people don't just ask him. ;-)

I have an older MintLP for my Triplanar that does show the material under the overlay has turned brown like the OP reports. The overlay itself is clear and clean. This material under the overlay appears to be an aide to facilitate using the mirrored surface. I suspect Yip may have found a substitute at some point that doesn't fade like this.

I don't think this is a cleaning issue. However, from the front page of the MintLP intstructions:

"The plastic surface can only be cleaned with lighter fluid [i.e. white petroleum] by a soft dry cloth. WATER, and any other kind of cleaner, water base or whatever, SHOULD NEVER BE USED.

I have no financial interest in MintLP, but I am a very happy customer.
You are correct sir, that my manual as well says only the use of Lighter Fluid as a cleaner.

Why I thought alcohol, is beyond me, and it seems like so long ago, that I do now forget what I actually used as a cleaner? lol

I do have lighter fluid around here, but if I did mistakenly use Alcohol, that could be the reason why I'm noticing a brownish tint to the Applique Overlay Sheet?

As another poster has mentioned though, the Protactor seems to have no other faults other than this brownish tinge, and certainly doesn't appear to warrant a return all the way back to Hong Kong.

I did email Yip, but haven't heard back from him. In any case, I'll live with mine, and as I've previously mentioned more times than I can count in other threads, it is a really great tool! Mark
The Mint LP a great tool. I will say that the only limiting factor to its effectiveness for me is my rapidly deteriorating middle-aged eyesight. At least my hearing isn't changing as fast. LOL.

the discoloration I see is definitely under the overlay. It looks like Yip scrapes this material away from the area around the null points, and at those points I see no discoloration. This is why I believe it is not the surface of the overlay. If yours is not foggy looking after using the alcohol I wouldn't worry about it. But, don't do that. Obviously. :-)
I compared the two Mint LPs I still have. The older one that came over 2years ago for the Triplanar does have a copper hue or tinge as compared to the one I received with the Talea(thanks Dan), which has a silvery white background. On second thoughts am not entirely sure if the older Mint was always this way. More important this is, I am sure, a cosmetic difference, and has no effect on usability .
I have 5 Mint LP Best Tractor since 2008 and no one of them presents the problem described by Markd51