Best UV Marker

[+gcnurse]

Hello,

 

I want to incorporate UV in my first cache, a multi cache. I purchased a UV marker to write the coordinates on a piece of paper in a Bison tube for the first stage. Unfortunately even though the marker is clear, it is still legible on the paper even without a UV light. If you hold the paper at the right angle you can read the ink even though it is clear. Does anyone know of a good marker that actually dries clear and truly needs a UV light to be able to read the ink? The one I purchased is the one for sale on the geocaching.com website.  Or maybe a different material other than paper that I could write on that wouldn’t be so easy to read the UV ink without the UV light? It kind of defeats the purpose if you can read it without the flashlight. 

Edited August 9, 2020 by geocachingnurse

[+funkymunkyzone]

Maybe try that marker with some waterproof paper, like rite in the rain?

 

I dabbled with UV clues for a few multis, and I laminated the clues to try and make the clues weatherproof and prevent the ink "wearing off", but ultimately the ink just spread and blurred. Admittedly I was using ordinary paper. I did find that the UV ink was best kept out of the sunlight.

[+Lynx Humble]

6 hours ago, geocachingnurse said:

Hello,

 

I want to incorporate UV in my first cache, a multi cache. I purchased a UV marker to write the coordinates on a piece of paper in a Bison tube for the first stage. Unfortunately even though the marker is clear, it is still legible on the paper even without a UV light. If you hold the paper at the right angle you can read the ink even though it is clear. Does anyone know of a good marker that actually dries clear and truly needs a UV light to be able to read the ink? The one I purchased is the one for sale on the geocaching.com website.  Or maybe a different material other than paper that I could write on that wouldn’t be so easy to read the UV ink without the UV light? It kind of defeats the purpose if you can read it without the flashlight. 

Very few geocacher have an UV light so I wouldn't recommend to use that concept for your first cache.

[+niraD]

I've seen UV caches that use non-fluorescent ink/paint as camouflage. Without UV, there's too much information, most of it irrelevant. With UV, only some of the writing stands out.

 

But the owners have mentioned that all of them need regular maintenance, to refresh the fluorescent ink/paint, which fades with time.

[+on4bam]

3 minutes ago, Lynx Humble said:

Very few geocacher have an UV light so I wouldn't recommend to use that concept for your first cache.

 

It's something I've had in my backpack for years. There's an attribute for UV light required, so there's no reason for not using it in a cache, especially a multi where reading the listing is almost always a must.

Instead of writing on paper, other materials may be used, we've seen UV writing inside birdhouses (wood), on laminated cards and petlings (plastic)... it seems to decay on paper fast if in direct sunlight and remain in good condition when stored in the dark.

 

 

[+kunarion]

9 hours ago, geocachingnurse said:

Hello,

 

I want to incorporate UV in my first cache, a multi cache. I purchased a UV marker to write the coordinates on a piece of paper in a Bison tube for the first stage. Unfortunately even though the marker is clear, it is still legible on the paper even without a UV light. If you hold the paper at the right angle you can read the ink even though it is clear. Does anyone know of a good marker that actually dries clear and truly needs a UV light to be able to read the ink? The one I purchased is the one for sale on the geocaching.com website.  Or maybe a different material other than paper that I could write on that wouldn’t be so easy to read the UV ink without the UV light? It kind of defeats the purpose if you can read it without the flashlight. 

 

I had no luck with party favor style invisible ink pens, or even office supply "security pens".  So I searched for industrial grade ink, and found maxmax.com:

https://maxmax.com/shopper/category/9302-phosphors-dyes-inks.  They had disposable plastic felt-tip pens in a variety of inks.  Looks like now you can buy the ink and a refillable pen.  Prepare for a price shock (plus shipping).

 

I found different colors, different wavelengths, even a stamp pad.  Also there's special slow-dry ink that makes writing a message easier.  My intention was to see if I could use different wavelengths to hide a very tricky message (ever try a rock light with selectable wavelengths?).  One thing I noticed was that some inks are much brighter than others using a common UV flashlight.  The other thing was that while some pen ink was visible as a watermark once dry, some vanished on paper.  Beware that once the paper gets even slightly wet, the message can become visible.  And that even laminated paper can get wet after sitting in water for a while.

 

I also learned that they aren't especially consistent in manufacture, so you just have to try it.  And that the pens dry out quickly, and when you want to reorder the kind that worked, they've discontinued that kind.

 

If you just want to try stuff, buy an inexpensive pen at a store and see if it's OK.  Or you could ask a company that makes the ink, such as maxmax.  Find out which ink disappears (won't watermark the paper) and also glows brightly using inexpensive UV LED flashlights that Geocachers may have.

 

Good luck!

 

 

Edited August 9, 2020 by kunarion

[+cerberus1]

1 hour ago, kunarion said:

Find out which ink disappears (won't watermark the paper) and also glows brightly using inexpensive UV LED flashlights that Geocachers may have.

 

Yep.  Not too many folks will carry a hundred buck light used infrequently.    Our closest last checked was over a hundred miles away.

We picked up a pak-lite (attaches to a nine volt battery) thingy for motel rooms.      

[+on4bam]

1 hour ago, cerberus1 said:

 

Yep.  Not too many folks will carry a hundred buck light used infrequently.

 

 

Looks like you're shopping in the wrong places . I don't remember exactly but I'm sure we paid less than €10.

 

[+cerberus1]

32 minutes ago, on4bam said:

Looks like you're shopping in the wrong places . I don't remember exactly but I'm sure we paid less than €10.

 

Not at all, and you've proved my point.       The need to have a quality UV surface, because most folks won't have a high-end light.  

[+Lynx Humble]

7 hours ago, on4bam said:

 

It's something I've had in my backpack for years. There's an attribute for UV light required, so there's no reason for not using it in a cache, especially a multi where reading the listing is almost always a must.

Instead of writing on paper, other materials may be used, we've seen UV writing inside birdhouses (wood), on laminated cards and petlings (plastic)... it seems to decay on paper fast if in direct sunlight and remain in good condition when stored in the dark.

 

 

It might be different in Germany but here in Canada I have over 12500 founds and I have found a grand total of 3 with the UV attribute so it's definitely hyper rare over here so an UV lamp isn't part of my kit.

[+The Jester]

I have over 9300 finds and have 7 with the UV attribute (some didn't require it, so I'm not sure why they are there) and have done a few with UV before the attributes.  But before I got my UV light I'd skip those that needed it (one of the reasons I bought a UV light), so I'm not sure how stats can prove or disprove the use of a UV light. 

 

I've seen UV reactive beads for kids bracelets  (if they change color you need sunblock).  I've thought of a couple of ways those could be used for a night cache...

[+KBLAST]

I have seen lots of caches where UV lights were necessary. It is a tool in my bag. UV flashlights are not that expensive. This is not the point of this post, but I love people who do interesting things for caches and love that the OP cares enough to make something quality and would hate if they were discouraged by naysayers.

[+on4bam]

1 hour ago, Lynx Humble said:

It might be different in Germany but here in Canada I have over 12500 founds and I have found a grand total of 3 with the UV attribute so it's definitely hyper rare over here so an UV lamp isn't part of my kit.

It might but I only have 4 finds there.

On a total of 10000+ I have 69 with the UV light required attribute. Since we tend to prefer caches that offer "a bit more" we may have an higher amount of these caches than average.

Filtering my Belgian database there are still 228 UV light required caches to find out of 37000+

 

[+on4bam]

1 minute ago, KBLAST said:

I have seen lots of caches where UV lights were necessary. It is a tool in my bag. UV flashlights are not that expensive. This is not the point of this post, but I love people who do interesting things for caches and love that the OP cares enough to make something quality and would hate if they were discouraged by naysayers.

 

Caches requiring UV light most of the time are less "plain vanilla" and, for us, more interesting just like caches with "tools required" and "field puzzle" attributes.

We had UV tags with coordinates for the next WP, UV lock codes, UV hints, UV values for bonus caches....

[+kunarion]

16 hours ago, geocachingnurse said:

Unfortunately even though the marker is clear, it is still legible on the paper even without a UV light.

What if you don’t use paper?  Rocks that have calcium (like limestone) or phosphorus glow in UV light, there are various colors, and they never wear out.  Pebbles or sand could be glued to an object in the shape of clues.  Glue non-glowing sand of the same color to fill in the space, and you don’t see the code until you use the UV light.  I’ve thought of doing that with some rather large rocks, but I’m still thinking it over. 

 

You can do a similar thing with ordinary paper by using a light colored pen or highlighter.  Maybe you can obscure the “visible” watermark with carefully placed lines.  Remember you can likely write a completely unrelated message in ordinary ink, directly over your invisible ink message, and it can still work.  It helps hide the watermark of the “invisible ink” pen.

 

 

Edited August 9, 2020 by kunarion

[+Lynx Humble]

1 hour ago, on4bam said:

It might but I only have 4 finds there.

On a total of 10000+ I have 69 with the UV light required attribute. Since we tend to prefer caches that offer "a bit more" we may have an higher amount of these caches than average.

Filtering my Belgian database there are still 228 UV light required caches to find out of 37000+

 

I just made a Pocket Query for Canada and of the 248 324 available cache there are just 171 with that attribute. In Nova Scotia it's even worse for 21 988 caches there are only 2...

 

I checked Pennsylvania where the OP is from and of the 39 561 caches there are only 25 with that attribute so I am intrigued why he is going that route for his first geocache.

 

[+K13]

11 minutes ago, Lynx Humble said:

I just made a Pocket Query for Canada and of the 248 324 available cache there are just 171 with that attribute. In Nova Scotia it's even worse for 21 988 caches there are only 2...

 

I checked Pennsylvania where the OP is from and of the 39 561 caches there are only 25 with that attribute so I am intrigued why he is going that route for his first geocache.

 

 

I suspect because there are so few like that.

[+colleda]

19 hours ago, geocachingnurse said:

Hello,

 

I want to incorporate UV in my first cache, a multi cache. I purchased a UV marker to write the coordinates on a piece of paper in a Bison tube for the first stage. Unfortunately even though the marker is clear, it is still legible on the paper even without a UV light. If you hold the paper at the right angle you can read the ink even though it is clear. Does anyone know of a good marker that actually dries clear and truly needs a UV light to be able to read the ink? The one I purchased is the one for sale on the geocaching.com website.  Or maybe a different material other than paper that I could write on that wouldn’t be so easy to read the UV ink without the UV light? It kind of defeats the purpose if you can read it without the flashlight. 

I have a cache set up just like the one you're proposing. I have not yet found a satisfactory UV pen. The problem is the UV ink fading over time. After replacing the paper a few times I have resorted to marking tiny dots, under and equivalent to, each number in case the seeker cannot make out the UV (or doesn't have a UV light) and included a hint to that effect.

GC6470N

 

[+cerberus1]

6 hours ago, kunarion said:

What if you don’t use paper?  Rocks that have calcium (like limestone) or phosphorus glow in UV light, there are various colors, and they never wear out.  

Pebbles or sand could be glued to an object in the shape of clues.  Glue non-glowing sand of the same color to fill in the space, and you don’t see the code until you use the UV light.  I’ve thought of doing that with some rather large rocks, but I’m still thinking it over. 

 

That's a clever idea.     

On/off a trail, a "rock" in the daytime isn't visible , and shouldn't get swiped like tacks n things (hunters "reusing" them mostly here), but create enough glow to show the next location, and  be a little eerie.  

Or some strontium aluminate glued to cut logs as "arrows" too.   I made note JIC that might work here...   

I have a lot of franklinite, and a couple fluorite and willemite large pieces...my Grandfather dropping some off every time he visited "the poconos" from NJ when a kid. 

He must have thought I was nerding out,  dropping off a couple commercial UV lights too,  and I just thought they looked cool along with the posters on the walls.  

 

[+on4bam]

7 hours ago, Lynx Humble said:

I just made a Pocket Query for Canada and of the 248 324 available cache there are just 171 with that attribute. In Nova Scotia it's even worse for 21 988 caches there are only 2...

 

I checked Pennsylvania where the OP is from and of the 39 561 caches there are only 25 with that attribute so I am intrigued why he is going that route for his first geocache.

 

Maybe to offer something more special than "plain vanilla"?

Isn't creativity something we all look for?

[+RocTheCacheBox]

15 hours ago, Lynx Humble said:

I just made a Pocket Query for Canada and of the 248 324 available cache there are just 171 with that attribute. In Nova Scotia it's even worse for 21 988 caches there are only 2...

 

I checked Pennsylvania where the OP is from and of the 39 561 caches there are only 25 with that attribute so I am intrigued why he is going that route for his first geocache.

 

 

I'm intrigued as to why you would discourage someone from making a cache that is rather unique.

I applaud and welcome more variety. Personally I would rather own and see placed a unique cache that effort has been put into, that is found less frequently, gets a higher percentage of favorite points and sets a better example of quality.  There is FAR too many low quality caches in place as it is.

[+kunarion]

10 hours ago, cerberus1 said:

 

That's a clever idea.     

On/off a trail, a "rock" in the daytime isn't visible , and shouldn't get swiped like tacks n things (hunters "reusing" them mostly here), but create enough glow to show the next location, and  be a little eerie.  

Or some strontium aluminate glued to cut logs as "arrows" too.   I made note JIC that might work here...   

I have a lot of franklinite, and a couple fluorite and willemite large pieces...my Grandfather dropping some off every time he visited "the poconos" from NJ when a kid. 

He must have thought I was nerding out,  dropping off a couple commercial UV lights too,  and I just thought they looked cool along with the posters on the walls.  

 

 

Hardware stores supposedly have phosphorus powder for adding to paint to make colors more vibrant (just like laundry detergent once had).  After an online search just now, I wasn't immediately able to identify which product it is.  But two pots of identical paint, one with phosphorus mixed in, seems like a plan to me.

 

Also, some fishing line glows, some does not.  And certain plastics.  There could be a 7-segment "LED display" made if fishing line, where the numbers glow.

 

I know this original question is about paint pens.  But if I'm making a glowing cache, I don't want to re-make the thing every time the "ink" wears out.  That is, I engineer the part that's often the most disappointing (where cachers arrive to find the UV ink failed after a shorter time than I'd hoped), so that part is the most durable. 

 

 

Edited August 10, 2020 by kunarion

[+Lynx Humble]

4 hours ago, RocTheCacheBox said:

 

I'm intrigued as to why you would discourage someone from making a cache that is rather unique.

I applaud and welcome more variety. Personally I would rather own and see placed a unique cache that effort has been put into, that is found less frequently, gets a higher percentage of favorite points and sets a better example of quality.  There is FAR too many low quality caches in place as it is.

I am not against someone making a unique geocache and I have the same opinion as you there are TONS and TONS of crappy geocache out there already.

 

My issue are that a percentage of first cache have crappy coordinates, placed in questionable area or hidden in plain sight for exemple. So the OP will have to overcome those type of issues and adding even more with the fact that his geocache will be higher maintenance for a lower numbers of find.

 

Personally I would have started with something simpler.

 

 

[Keystone]

Soooo... does anyone know of a good UV marker?  Let's get back on topic.

[+TmdAndGG]

I've never tried it so I can't tell you how well it works, but I know they sell one at Shop Geocaching.

https://shop.geocaching.com/default/invisible-ink-uv-marker.html

[+kunarion]

4 hours ago, TmdAndGG said:

I've never tried it so I can't tell you how well it works, but I know they sell one at Shop Geocaching.

https://shop.geocaching.com/default/invisible-ink-uv-marker.html

That’s a paint pen, so it makes a “clear” line, a visible line, and that brings up the original question of cachers seeing the message without using a UV light.  One thing I discovered when testing my pens is if I soak the paper in water, the message appears.  And paper gets wet in caches.  Otherwise, that paint pen could be pretty cool, if the watermarked ink of the message can be obscured in some way.

 

My ink pens were more like Sharpies, alcohol-based ink that completely vanished after the ink evaporates from paper. But as to how well any of it works in a cache application... you just have to try it.

[+gcnurse]

13 hours ago, RocTheCacheBox said:

 

I'm intrigued as to why you would discourage someone from making a cache that is rather unique.

I applaud and welcome more variety. Personally I would rather own and see placed a unique cache that effort has been put into, that is found less frequently, gets a higher percentage of favorite points and sets a better example of quality.  There is FAR too many low quality caches in place as it is.

So this is exactly why I want to do this. Many of the caches locally to me are kind of boring. Easy to find, Rx bottle under a lamp post base, etc. I want to make one that requires something a little extra and doing a multi-cache allows me to hide a small bison tube in an easily accessible area out of sight that will lead to a large ammo can in a not so easy to find area. Additionally, there is a Walmart and Lowe’s near my planned hiding place that both sell UV flashlights for around $9-$10. So for those without one in their kit, they can pick one up if they desire to pursue the cache. I’m trying to inspire a little more creativity locally and have been scouting out the location and the plans for this cache for the past 2 weeks. My plan is to make the locations for the multicache across a local park to encourage people to explore the trails. 
 

I guess everyone has their own preferences, but I’d like to put out a few unique caches rather than a bunch of simple ones. 
 

thanks everyone for the replies, definitely inspired some ideas. I have a little more researching to do. 

[+gcnurse]

On 8/9/2020 at 8:59 PM, colleda said:

I have a cache set up just like the one you're proposing. I have not yet found a satisfactory UV pen. The problem is the UV ink fading over time. After replacing the paper a few times I have resorted to marking tiny dots, under and equivalent to, each number in case the seeker cannot make out the UV (or doesn't have a UV light) and included a hint to that effect.

GC6470N

 

I found a fountain pen ink online that I’m going to try: https://www.gouletpens.com/products/noodlers-blue-ghost-3oz-bottled-ink

 

the reviews seem to suggest it is truly invisible once dry and is permanent. My plan is to try to laminate a piece of paper with the coordinates and then place that in a small zip lock bag inside the bison tube if it it’s truly invisible. We’ll see how it works out. I’ll post back once I get the ink. If it works well I can send you some as I’ll never use the whole bottle of it. 

[+NYPaddleCacher]

On 8/10/2020 at 9:57 AM, RocTheCacheBox said:

 

I'm intrigued as to why you would discourage someone from making a cache that is rather unique.

I applaud and welcome more variety. Personally I would rather own and see placed a unique cache that effort has been put into, that is found less frequently, gets a higher percentage of favorite points and sets a better example of quality.  There is FAR too many low quality caches in place as it is.

 

For as long as I've been reading these forums I've observed that many new caches are enthusiastic about creating a new cache and try to come up with something unique (rather difficult for a game 20 years old).   It's great to see that kinds of enthusiasm but  creating something unique typically means creating a cache that is more complex that might require some special maintenance needs.   That's why I often suggest someone that is considering a "unique" cache as their first hide to hide a couple of "basic" caches first to get the sense of cache ownership before tackling something more complex.

[+colleda]

My first cache was hidden in a hollow of part of a dead tree (that had been killed by a strangler fig). I sawed off a very a small piece of dead wood so that I could cover the cache with a cammo cap using piece of dead wood I had found on the ground. Pleased with my work I waited for the FTF to log. It soon was. Left a nice log too. Feeling chuffed after the FTF log the 2TF (who was the local FTF hound at the time) left this, in part;

"This is a nice little area, and there were a few people around, but none near GZ. Once the cache was spotted, I almost couldn't believe it...as one cache gets archived this week for hacking into a tree...another one pops up. However, after correspondence with the owner, almost no damage has been done to the tree...and for that I commend you for it! I like the concept of hide...Very well done!" My heart sank for a second. I appreciated the 2TFer contacting me and imparting wise words. Lesson learned. No more cutting.

Later on the dead part of the tree was hacked off by a chainsaw wielding muggle needing firewood. I had already moved the cache to another part of the tree in a similar hide. The cache is still going although finds are few these days.

 

[+gcnurse]

On 8/11/2020 at 12:33 AM, geocachingnurse said:

I found a fountain pen ink online that I’m going to try: https://www.gouletpens.com/products/noodlers-blue-ghost-3oz-bottled-ink

 

the reviews seem to suggest it is truly invisible once dry and is permanent. My plan is to try to laminate a piece of paper with the coordinates and then place that in a small zip lock bag inside the bison tube if it it’s truly invisible. We’ll see how it works out. I’ll post back once I get the ink. If it works well I can send you some as I’ll never use the whole bottle of it. 

So I got this ink in the mail today, it is exactly what I was looking for. Truly invisible and leaves no watermark. Even on cheap printer/copier paper. Highly recommend if you’re looking to experiment with UV.  Two pictures of the same paper with writing, one with UV flashlight and one without. Pretty impressed with it!