Ideas for USB Device Lanyard Attachment?

[MrAl]

Hi,

I got a new USB device yesterday that did not come with a lanyard and it doesnt even have a hole or a place to drill a hole for a lanyard. I'd like to attach a lanyard so i can carry it around the same way i carry my USB drives (with a lanyard).
It is the same size and shape as a standard USB drive. One side of the device however is reserved for plugging in a SDHC card so most of that side cant be blocked. The other side is free however.

Any ideas for attaching a lanyard?

I was thinking of wrapping a strong cord around the device and gluing it in place with epoxy, but if i do that and it stop working and has to be returned to the manufacturer it will look like it had been modified so might void the warranty.

Any other ideas?

 

[Mickster]

You might wish to take a look at Polymorph, Shapelock, or Friendly Plastic as a potential candidate (common names for the product).

You could easily make a holder which is firmly attached to a lanyard, but allows the USB device to be slid out when usage is required and makes no permanent attachment to the device itself, thus not voiding any warranty.

Regards.

EDIT:

I've used this stuff for all sorts of things, but one of the most attractive features of this product is the low melting point. If you need to make small changes to a particular application, such as gripping pressure, you can do it practically anywhere. If you have a lighter, hair-dryer, kettle, stove, heater, even eye-glasses and sunlight, you can tweak to your heart's content.

 

[MrAl]

Hi Mickster,

Oh so you are suggesting that i make my own holder? That's not a bad idea really. I could make it with a lanyard hole for easy attachment. I happen to have some fiberglass resin and mat which might be a possibility. I'd just have to make a mold.

 

[Mickster]

You could use fibreglass resin & mat, but as you say, you may have to make a mold first.

I used Polymorph for the crude exercise below, using an old USB drive.
It took between 5 & 10 minutes from heating to moulding to cooling.

EDIT: If you don't like the results the first time around, simply re-heat the stuff and start again.

 

[MrAl]

Hello,

Ok i think i'll try some of that stuff. Thanks for the tip.
What else have you used it for so far?

 

[Mickster]

Amongst other things, I've repaired a cold water pressure washer outlet connector for a friend.
He had left it over the winter, with water still inside, which froze and cracked the plastic tube.
I heated & then moulded the polymer around the pipe, let it cool, then wrapped it very tightly with electrician's tape.
Next, it was dropped into hot water (>62°C) for a couple of minutes, then allowed to cool again.
AFAIK, it is still working and hasn't leaked.

I also made a flexible shaft, with adapters for the end, which grip certain sized fasteners such as nuts/bolts, in order to aid thread-starting in difficult to reach areas.
I managed to get a Torx-head & E-Torx-head bolt to be held quite securely!
Pics below (Sorry for the dirt on the tool, but it has been used )

It has also been used on an Xbox360 controller, plugging a small drilled hole on the top, but still allowing an LED to shine through.

I think that once you have some, the potential uses are quite large.

 

[MrAl]

Hi again,


Thanks for the pics, very informative and certainly interesting. Maybe you or i should start another thread about this stuff as it does look as you say with the potential for many uses in electrical and many other too.

I should have a sample by the end of the week. Cant wait to try it now even for other things

What is that last pic of (the darker one)? The part looks a little burnt or something.

Any idea what the shelf life is? I ask because i've had so many other things that dry up after a year or two like Gorilla glue.

 

[Mickster]

Hi Al,
the last pic is of the end of one of the flex shafts and the underside of one on the attachments.

The flex shaft has a 1/4" square drive and the attachment has the same 1/4" square socket.

They mate together with a firm push-fit and make a satisfying 'pop' when pulled apart.

The part does look a little darker, partly due to trying to take a macro-shot in poor light, but also in part due to having been used with oily hands, which also lends a hint to the fact that the polymer can also absorb substances.... i.e. colouring agents. ;-)

Not sure what the shelf-life is, the product is supplied in granular form and I have a couple of 500g tubs, which don't exhibit any signs of degradation after perhaps 3 or 4 years following purchase.

It's chemical name is polycaprolactone.

Decomposition starts to occur at 200°C and can release CO/CO2, so direct application of a high temp heat source is discouraged. I prefer to use a small stainless steel parts dish and wave a butane pencil torch, with a heat-shrink attachment, from about 3 inches away until it starts to become transparent.

MSDS sheet:
https://www.electro-tech-online.com/custompdfs/2012/08/capa3301_080325-1.pdf

Regards.


EDIT:
Having looked at the 3rd pic again, the darkest bits on the square drive are from where the shaft was inserted into the bottom of a 1/4" drive socket for moulding. This process, applied to a regularly used socket, has picked up some of the grease/grime which was in there.

 

[MrAl]

Hi again,


Thanks for the info. BTW, how are you handling the stuff once it is hot, like when you have to mold it around something else to get it to assume that shape?

 

[Mickster]

Hi Al,
I just mould it by hand. My hands are pretty leathery due to many years of manual work and working around hot things, so I guess I tend not to be bothered by it.

Perhaps I should redo the USB device holder again & check the polymer temp when it becomes transparent?

I have a Raytek Minitemp https://www.thetoolwarehouse.net/p-4801-raytek-mt4u.aspx which should be up to the task, unless the transparency gives false readings?.

The granules were heated in the stainless steel dish until they became transparent, kneaded together to form 'blob', then flattened into a roughly rectangular shape. From there, I wrapped the polymer around the USB drive & waited for it to start to become opaque. At that point, I created the lanyard hole with a pair of needle-nose pliers and left it to harden fully.

Once hardened (the polymer returns to it's original colour) I eased the holder away from the USB drive at the open edges on the top, then worked it about a little, to free the drive. I think the polymer has a tiny amount of shrinkage as it hardens, since the USB drive is a very good fit and although I haven't yet tried it, I bet I could swing it around leisurely without it falling out.

.........

OK, I've just tried swinging it around like a propeller and I'd estimate about 4 or 5 revs/second before it comes out.

Any more info I can provide?

Regards.

EDIT:
I've just re-melted the polymer & checked the temp at the point of becoming transparent.
The Raytek showed around 60°C, which roughly ties in with the datasheet.
During handling & checking temps, the polymer remained pliable down to around 35/40°C.
I had to re-heat it a little more & stretch it out, in order to wrap it around the drive fully, due to checking temps.

 

[MrAl]

Hi,

Thanks again for the info there, with your pics and descriptions i have a good idea what kind of material i am (or will be) dealing with. This stuff really does sound good especially since i have other things i have to do which requires building a mold and laying up with fiberglass. I have been using plaster of paris, which is a little bit of a pain because it remains porous when dry. I have to paint the mold before i can use it.

Well as far as more info, you've already presented a good view of what this stuff can do and how easy it is to use, but if you feel like doing another experiment that's cool too. Does the stuff bend once it is hard, like in 1/8 inch thickness? Or maybe 1/16 inch thickness, and what thickness does it take to stop it from bending too much, or is it very brittle like glass once hard?
I've found epoxy very useful in the past. Can you compare it to epoxy once the epoxy is hardened (other than melting temperature)?
Taffy (the candy) melts pretty easy, can you compare it to taffy when the taffy is hard?
Also, any stickiness once it is hard, like does it feel tacky like paint that isnt all the way dry?
How about when it is still soft, does it feel sticky at all or more like a ball of wax?

 

[Mickster]

Hi,

Thanks again for the info there, with your pics and descriptions i have a good idea what kind of material i am (or will be) dealing with. This stuff really does sound good especially since i have other things i have to do which requires building a mold and laying up with fiberglass. I have been using plaster of paris, which is a little bit of a pain because it remains porous when dry. I have to paint the mold before i can use it.

If your intention is using this polymer for producing a mold to be used directly with a fibreglass mat & resin layup, I'd suggest you try a test-piece first and check the temp of the fibreglass during the curing process.

Well as far as more info, you've already presented a good view of what this stuff can do and how easy it is to use, but if you feel like doing another experiment that's cool too. Does the stuff bend once it is hard, like in 1/8 inch thickness? Or maybe 1/16 inch thickness, and what thickness does it take to stop it from bending too much, or is it very brittle like glass once hard?

The flexible shafts, referenced in the previous pics, have an approximate diameter of 5mm. The longer shaft of the two measures roughly 300mm between the 1/4" square and the splined hub. It can be flexed to form a complete circle with both ends touching. Doing so appears to produce a small memory effect, when relaxed, but this can be manipulated somewhat and the shaft returned to a fairly straight condition.

I haven't experimented with any required material thickness to actually resist bending thus far.

The polymer is not brittle when hard.

I've found epoxy very useful in the past. Can you compare it to epoxy once the epoxy is hardened (other than melting temperature)?
Taffy (the candy) melts pretty easy, can you compare it to taffy when the taffy is hard?
Also, any stickiness once it is hard, like does it feel tacky like paint that isnt all the way dry?
How about when it is still soft, does it feel sticky at all or more like a ball of wax?

I'd have to say that we are comparing two entirely different products. Epoxy resin sets hard enough to be drilled, or tapped, and fractures easily when stressed.
Polycaprolactone, although setting pretty firm, seems to be still flexible to a certain degree dependant upon thickness and not very tolerant to drilling, due to it's low melting point. There appears to be no stickiness once hard and yes it does appear to feel a little waxy, but it is slightly tacky whilst pliable.

For more information and demonstrations of how this polymer has been utilised in functioning machines, please check this link:
https://reprap.org/wiki/Polycaprolactone

 

[MrAl]

Hi again,


Thanks again for this information. I see this as valuable information because
we never know when we have to fix something important or need to make something
in a hurry that would benefit us in some way. This stuff is quite interesting
because it allows us to do things that are otherwise very hard to do and usually
take a lot more time. I'll also take a look at your link.
I was aware of the fiberglass heating during the cure issue. I've seen fibreglass actually
smoke when it was curing, usually the thicker the hotter, and the more cat the hotter.

I managed to get a some of this stuff, a 12 ounce can. I've tried a few things
already so ill list them here.

First, i made little fingr grips for one of those black paper clamps, the kind
you squeeze the handles and it opens then you put the sheets of paper in and
then release the handles and it holds the paper. I use them for various things,
but this was just because i wanted a simple test that didnt use too much
material at first just so i could get an idea how this stuff worked and how to
manage it.
It worked out pretty well. I put some of the beads (the stuff came in beads)
into the hot water (around 200 degrees F) and let it sit for a minute, but
noticed that it got clear very quickly probably because that is hotter than
usual for this material. It appeared to look almost exactly like fish eggs
sitting in the bottom of the cup, because the beads became clear (i assumed
they were now soft) but they did not join together automatically as i thought
they would (why i thought this im not sure, probably because i've used various
resins in the past). So after about a minute i stuck a hemostat into the water
and poked at the substance which still looked like fish eggs. They seemed soft
but not too soft, sort of like medium rubber. Since they did not seem to be
joining, i pushed them together a little with the hemostat tips. This allowed
me to form a cube of the material (well more like a stretched out cube). I think
pulled it out of the water and it was cool enough to handle so i formed it into
a long stick like structure (about 5 inches long) that was about 1/2 inch wide
and about 1/4 inch thick. I then pulled off two pieces (it pulls like taffy)
and squashed them thinner and then wrapped them around the handles of the black
paper binder clip forming two handles. With the remainer of the piece (now about
3.5 inches long) i formed it into a piece that came out to be about 3/16 inch
thick on one end and about 1/4 inch thick on the other. It looked rather solid
now because i had squashed the 'fish eggs' together to form a solid piece.
It was kind of clear but a little foggie looking. I put it down to let it cool.

About 15 minutes later, i checked the binder clip and the handles had hardened
quite a bit but the 3.5 inch thicker piece did not get too hard yet. It was
way too easy to bend to be useful. I was wondering how long it took to get
harder.

About 30 to 45 minutes later i checked the long piece again, and it was getting
a lot harder now. It was much harder to bend now. In fact, it started to act
like a piece of actual plastic.

About another hour or so later i checked it and it was quite hard now. Not super
hard but about the same as some average plastic. It wasnt super hard but it
wasnt very soft either. Clamping one end of the 'stick' down (by about 1/2 inch
of the material length) and applying about 1 pound of force at the other end
would bend it about 1/8 inch down at that one end. That's not bad really.
Because of this test i could easily see this working in a variety of applications,
as long as they dont get too hot during normal operation.

The binder clip was much easier to squeeze together now having those little handles.

Conclusions i've reached after these two simple tests, first the good then the bad:

GOOD
1. Easy to use. Melts in hot water and handles easily.
2. Can be used in a variety of applications.
3. Makes a quick mold.
4. Can be re-melted and used again.
5. Seems to act with the strength of some plastics when hard, fairly strong.
6. Not brittle, wont break if dropped.
7. I have read that this stuff bond with ABS plastic. Nice! Havent tried it yet though.

BAD or just not that good:
1. Cant use it near hot objects like heat sinks or power resistors. Max temperature
is probably 120 degrees F but i didnt test this, it could be lower but not much higher.
2. Not that cheap.

One little strange thing is that i had to push all the little 'fish egg' blobs
together before i could use it. It handled like semi wet clay.
This isnt a huge drawback though i guess.

What im not sure of yet...
1. How easy does it get contaminated with another substance.
2. How well does it hold up to various products like gasoline, alcohol, etc.
3. How well does it take paint, and what kind of paint.
4. How well it glues together, or what kind of glue to use.
5. Havent tried drilling it or tapping it, but i would think a very slow speed would be needed.

 

[Mickster]

Hi again Al,
I've only used the hot water method to heat the material once, since it tends to be a bit of messing about in my opinion.
One approach when using this method, is to have some form of hook to hand and clump the 'fish eggs' together with it, then pull the clump out of the water and squeeze it to force out the water. A simple piece of bent wire would suffice. I don't imagine you could get all of the water out using this approach and thus, I moved to using hot air.

It would seem from your own observations using water at 200°F, the material takes quite a long time to cool and the thicker the 'part' dimensions, the longer the cooling period. 200°F / 93°C appears to be above the temperature I have been using, since the consistency for me seems more firm like modelling clay, such as Playdoh, rather than wet clay.

Using hot air, such as my butane torch with heat-shrink tip, or a SMD rework station, or even a heat gun, as soon as the granules/beads/fish eggs become clear, I knead them together and start to form whatever shape I need. If I am a little slow and the material starts become opaque, or the 'part' is a little intricate, I can use a little more hot air to soften it again. You could, if using the hot water method, dip the 'part' in again to soften and rework it though.

I guess it basically comes down to what you have to hand. It seems like using water at the temperature you used gives you a higher working time and a more malleable consistency, coupled with absolutely no risk of reaching the temperature at which the polymer starts to degrade, but with the added effort of having to squeeze the water out first. The flip side, when using the hot air, runs the risk of either blowing the granules/beads/fish eggs around in the dish due to too much air flow, or potentially reaching the temperature at which the polymer degrades. I suppose that's why I keep a good distance and remove the heat as soon as the material goes transparent.

If you use a kettle though, you also have the opportunity to make a cup of tea or coffee too.

Your good and bad points are pretty much spot on, but if you take GOOD #4 into consideration, BAD #2 becomes less of an issue.

1. How easy does it get contaminated with another substance.
2. How well does it hold up to various products like gasoline, alcohol, etc.
3. How well does it take paint, and what kind of paint.
4. How well it glues together, or what kind of glue to use.
5. Havent tried drilling it or tapping it, but i would think a very slow speed would be needed.

1. The flex shafts and adapters in the previous pics have been handled with dirty oily hands. You can see that the material is now not quite the same nice white is was from the tub. In addition, I know it's not good for either myself or the PC, but I tend to smoke quite a lot at the PC and I have a small DIP-8 to SOIC homebrew stripboard adapter for EEPROMs and such, which got 'tidied up' with some Polymorph. It sits infront of the PC and has yellowed somewhat over the years due to smoke being drawn over it by the PC fans. I haven't tried yet, but I believe that colouring agents can be used. There is a Youtube link here:
https://www.youtube.com/watch?v=Po8BaYD9Wks

2. I cannot comment as I haven't tested this.

3. Again, I haven't tested this.

4. The best thing about this is, you don't need any glue. Simply locally heat two 'parts' where you need to join them and press them together. The flex shafts were made this may. The shaft itself was roughly formed and then rolled between two pieces of glass. Two rods were used as spacers, with the polymer inbetween. The 'knurled' handle was made by pressing the soft material into a former, which was actually the annular gear ring from an electric fuel pump. Once both parts were made, the centre of the handle was heated along with one end of the shaft. When both parts started to become transparent, they were mated and allowed to cool. The 1/4" square drive on the shaft was made in a similar fashion - the end was heated and pushed into the female square drive of a regular 1/4" socket, used as a former.

5. I too have not tried yet and agree that a very low speed would be necessary, but have just thought about creating threads... Why not mould the material around the threads of a bolt whilst making the 'part', then remove the bolt later and clean up where required?

I hope I've covered most, if not all, of your points and observations.

I do think this is one of those 'wonder' products, where you wonder how much more work/time/effort would be involved when using something else...

Regards.

 

[MrAl]

Hi again,


OH yes i have considered using the heat gun but havent gotten to that yet. I just wanted to follow the directions on the side of the can to make sure the first try was as per manu's exact directions. I've also read now that heating too hot could cause bad burns. Ive had the unfortunate opportunity to find this out first hand with hot glue when some dripped on my bare (in shorts) leg. Wow, and the bad part is you cant get it off to easily because it's stuck to your leg and hot as all heck. It burnt for a couple days.

Which brings me to my next thought...
I had been hoping for a substance that was like hot glue but more like plastic, so it melted at a lower temperature but cured like plastic or like epoxy. This stuff fits that niche quite well almost exactly. I also wonder if it would be possible to construct a hot glue gun just for this stuff and use it like glue. Probably possible using a normal hot glue gun with lower temperature (i'd have to check the actual temp of a hot glue gun here). Using rods instead of little balls would work well i bet. Yes more expensive than hot glue but that's life.

Yes reusing means less expense, but for my purposes most applications will be permanent or semi permanent over years so reuse wont mean as much to me as say someone who wants to make molds and then use it over again for another different type mold. If i make a mold for something chances are i dont want to destroy it but will want to make another of that object later down the road.

As to gluing i meant after the product has cooled. It wont stick to some materials even if hot and i wont always wish to reheat it. It's just that i havent tried it yet anyway either way so i'm in the dark for now. That will change soon though as i experiment more with it.

Really great product that's for sure. My next concern is longevity over longer periods of time. Some examples include:
1. Left in the open air how long does it remain pretty much the same, ie not start to decompose.
2. If touching the human skin how long before it breaks down if it does break down (wrist watch band for example not that i want one)
3. Touching other types of plastic for extended periods: if it is touching another object of the same stuff does it stick after a few months even though it wasnt to begin with yet fully cooled first. If touching other types of plastic does it stick after a few months. Some plastics do this. I'll have to test this myself i guess.

One very interesting application i saw on the web was where the guy made a potentiometer knob, custom fit to a surplus pot he bought. Many times we dont have a knob laying around and need something just to stick on there without gong through too much trouble. For example in a test power supply for the bench...i have one with very fine tuning voltage control but never got around to getting a nice knob for the pot. That's one on the list ha ha.

Ive also read that it is a very good electrical insulator which is REALLY nice

I would bet we could write like forever about this product and not say it all.

 

[KeepItSimpleStupid]

This company has some nice stuff: https://www.gearkeeper.com/gkaccess.html and I have some of it. There is an adhesive attachment at the bottom of the page, but they fail to tell how big it is. I think I got one of these with a retractable lanyard that I purchased from them.

 

[Mickster]

I would bet we could write like forever about this product and not say it all.

That's why I've firstly singled out this line from your above post..

I had been hoping for a substance that was like hot glue but more like plastic, so it melted at a lower temperature but cured like plastic or like epoxy. This stuff fits that niche quite well almost exactly. I also wonder if it would be possible to construct a hot glue gun just for this stuff and use it like glue. Probably possible using a normal hot glue gun with lower temperature (i'd have to check the actual temp of a hot glue gun here). Using rods instead of little balls would work well i bet. Yes more expensive than hot glue but that's life.

The RepRap foundation have been designing, producing and refining something along that line, although it is an actual μC controlled extruder for FDM rather than a derivative of a glue gun, but the research has been done and feed speed vs temp for various polymers is available on the site. Incidentally, the Mk1 Darwin machine was made using Polycaprolactone.

You do raise a very valid point about saving successful molds for re-use, but imperfect or simply ruined molds can be re-used without further material outlay. The same cannot be said for using resin & glass mat, to use just one example. However, if high curing heat is important and deformation is to be reduced, this is quite likely not the correct product.

As far as gluing/joining parts goes, I have only used the polymer to attach itself, to, erm, itself. There may be other ways to achieve this, but I'm afraid I haven't had to look at this scenario yet and your requirements may already surpass mine.

Looking at longevity in the open air... again, that is something I haven't yet had any reason to look at. I suppose prolonged UV exposure could be a factor?

I'm sure I read somewhere about this polymer being a potentially safe material for human implant, but had no reason to pursue the possibility any further. Google has an auto-complete when searching the terms and there are quite a few hits:
https://www.google.co.uk/search?sou...3.3.0.190.765.4j3.7.0...0.0...1ac.FJDIpBTk6GY

 

[Mickster]

For anyone following this discussion having little idea of the product in question, or it's potential use, here's a Youtube video describing the product, how to use it and some examples of how it can be molded and/or repeatedly worked:

https://www.youtube.com/watch?v=vzghjRrZZws&feature=related

I have no connection whatsoever with this video, the product, or any other link provided within this thread.