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Lexan melting and using in silicone putty based molds

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stringpickin1

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Mar 26, 2013
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Hello and good day.. Among other things I am a guitarist and have been trying to develop the perfect glue-on finger nail for finger-picking guitar players.. I have used acrylics personally for the last 25 years and have tried the old ping pong ball to gel, to lexan sheets bent and glued to my nails..

I want to make a mold of the acrylic nail(s) that I will be removing from my nail I built up on my nail(s) using common acrylic nail powder and monomer liquid. I then will embed them in the AeroMarine Silicone Rubber Putty material to create my two part molds.

Then I have in mind to melt lexan(probably from sheets I can easily acquire)..

My question(s).. Do you think I would need to use a a mold release. W
What would you recommend that I melt the lexan in.. steel pan, aluminum, ??
Am I believing that I will be able to pour melted lexan in these molds but yet it may not work because lexan when melted won't fill the mold without getting air bubbles or???
Any input is greatly appreciated..

I appreciate your help and advice, and mostly your time.. thank you..

string
 
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Be very careful when pouring this material. To get Polycarbonate plastic to flow well it has to be heated to close to 400degrees farenheit.
This is like playing with melted solder. if there is the slightest bit of moisture in your mold you will get more than just air bubbles, you will get an explosion.
Use a steel pan for heating the lexan and preheat your mold to at least 300 degrees.
B.E.
 
Why dont you use a 2k epoxy or up resin? there liquid at room temperature. You just mix in the b komponent, pour it out an let it cure.

If you use a silicone mould probably dont need any release agent.
 
Thank you Berkshire and Aeon!!

Good thing for me to be reminded about how volatile they can be. I will take that to good heed..

I am going to be melting relatively small amounts. There must be a small hopefully somewhat inexpensive metal melting crucible/kit or something out there that would help with that part.. I will have to check that out. And I will pre-heat that mold, thank you.

Aeon.. I have a couple of situations. I will be reproducing copies of my acrylic nails as I had explained I actually make on my own fingers. Then I will remove them and use them for my mold form. So the liquid mold product would work fine. I could actually use a square mold to poor the liquid in etc.. to make the actual mold easy to work with.

The other aspect is I want to be able to offer a service to guitar players. This is where the putty comes in. I need a copy of their fingers/nail tips so I can first build up the acrylic nails on so that I can then repeat the process with their own custom shaped nails. So I will be sending them the putty to mix, and they will insert their finger tips in the putty long enough for it to set up and retain the shape of their fingers and then let the putty cure and return it to me..

And on another note: I have been playing with this in my mind as well. It may be easier for my own lexan molded nails to actually start with embedded impressions of my nail beds/then build up the acrylics on those forms, then use the actual castings of my top finger nail cross-sections as the bottom part of the mold.. In this case the putty allows me to use my finger as the form and not have to wait too long before I can remove my finger..

So as you can see I am trying to formulate the most likely course of success the first time go..

any advice still appreciated..

thanks again.. String

 
Have you considered polycaprolactone ("hand moldable plastic" on inventables.com) for making your initial positives? Comes in pellet form, melts at 140*F, so in hot water or hit it with a heat gun (maybe even hair dryer) if in a rush for a small amount to work with. Cool enough that it can be worked by hand comfortably.

Is it the shape that is critical, or the rigidity of the material? I assume both, and the finished product couldn't be polycaprolactone. If nothing else, might save you some time with the acrylic when you are in the mold making stage.
 
Hi little late but nevertheless.

If it was me i would use some simple gypsum to cast a mold of the finger.

Take the mold en fill it up with a 2k epoxy, unsaturted polyeser, polyurethane or other casting resin. Let the material cure and then you have a perfect finger on which you can make de nails on.

when you do this make sure that you use a resin system with a low peak-exotherm! if this is to high the casting will burn in the thicker layers.
(peak exotherm is the build up of heat caused by the cure reaction.)
 
Hello everyone.. I am getting closer to my experiment with fingerpicking nails..

I have got rtv silicon with heat range up to 600f plus.. Going to be using 2 part clay/putty to make the mock up nails on my hands, and a ring part as well.

Back to the lexan and some new questions please.

1. When it melts does it create a slag of any kind on top making the use of a bottom poor ladle worth the extra bucks?

2. I am wondering if the acrylic powders that are used in the nail industry (two part- powder and monomer liquid) is close to the same thing as acrylic sheets used in aquariums or etc..

3. Is melting acrylic a different animal than melting lexan??

4. I have been looking at small furnaces.. Most that are made for lead melting do not have heat control.. I am thinking it would be very hard to turn it on and off to keep the lexan from getting to hot.. I have found a couple with heat control but the units are pretty big.. And when you don't have a bottom poor crucible in those things, don't you always have material in the crucible you can't get out? Or does the pot/crucible lift out so you can pour out the remaining product into your molds or ladle??

5. I had thought I may try melting acrylic and using it for the nail/picks being that the acrylic powder product works pretty dern well. Has a pretty good tone and feel and is actually pretty strong and durable..Is there an article or guide that you can steer me to that can possibly help me with types of materials I can mix together. Such as Lexan and acrylic, or nylon, etc..

sure appreciate your help..

I surely do appreciate your time very much if you choose to help this ignorant cuss.

thank you very much
String
 
Need to answer some questions about why you chose lexan, and what material properties are most important, before anyone can suggest alternates.
 
Thank you.

Chose Lexan because I found it readily and easily melts. It is also used by guitarists in sheet form to create glue on finger nails out of.. By taking lexan sheets and cutting small sections and then bending the pieces to the arch of the nail the pieces are then glued on and then filed and sanded.

Guitarists that have used it say the tone, the strength, the flex, etc. is very close to natural nail in the tone it produces as well as having some flex so it doesn't break if struck during working situations etc..

Main complaint of lexan is it is tedious to shape the pieces to the arch of the nail bed and time consuming to do the fitting and sanding and etc.. So my first thought was why not pour the lexan into the shape in a mold and save all that headache.. I am very excited personally to try it as a guitarist..

I have used acrylic nails for years. I taught myself how to apply them and intend on using the molds to make acrylic nails using the nails I build up on my fingers as mold positives..

Guitar picks are made of various materials.. polycarbonates of different types. Nylon, etc.. and I am sure that different manufacturers have their secret mixes.. I have one guitar pick that I LOVE because of the feel, how it bends, how it sounds, how well it holds up.. It is different than most any other pick I have ever used. But I doubt seriously if that manufacturer is going to give me the secret mix of compounds..

So I am hoping to find what would be the best and most common areas of products that could be mixed to give, strength, yet some give, durability but not so hard it sounds like metal chirping accross the strings.. etc..

In my minds eye without knowing for sure.. A mix between acrylic and lexan could be a good blend of properties. But can it be blended? Can sheets of acrylic be melted like lexan can and be mixed together in a mold.?

So, I am looking for blends of materials as listed above that can be heated/melted/mixed and poured into molds that could meet the specifications I basically laid out..

any other info needed I am happy to supply. thank you again for your time and help..
 
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