Using plastics and acrylics ?

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farmer

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I don't use plastics or acrylics in my work, main reason is I like a natural wood look..

My question is doesn't plastics and acrylics start to shrink after 4 to 5 years ?
 
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When I started turning pens in 1995, one of the exhibitors at the shows we did in Chicago was a guy named "Father Sing". If you look at the history of handmade penmaking (kits), you will find some of the earliest books were authored by this same, Dick Sing.

Seemed unfair for me to walk into the "sport" he created and become competition, so I asked him what he did not like to do. He replied, "Plastics"!

Very few were even attempting plastics at the time, but I made it my specialty. I have turned mostly plastic pens ever since. I have sold thousands and have a couple hundred stored in our "annex" building. They were made before 2008, when I turned my attention to ExoticBlanks and stopped making pens, for sale at shows. NONE of them is distorted in any way I can see. But, I always purchased fairly expensive blanks, most made in Italy. I bought directly from Europe. SOME were purchased from Woodcraft and their predecessors, again all pretty pricey.

So, I have seen other penmakers post that their "plastics" are shrinking. I certainly am not arguing with them, but my experience is different.

Perhaps it depends on the kind of "plastic".

FWIW,
Ed
 
I've never seen "plastic" pen material shrink, even with pens I made almost 10 years ago. The only time I heard of that happening was one penmaker's thread a couple of months ago.

Wood, on the other hand has, has occasionally cracked and split over time. I switched to acrylics to avoid the problem.
 
My question is doesn't plastics and acrylics start to shrink after 4 to 5 years ?

Yes, I have had that experience with what I think is Acrylic Acetate. I believe, but am not sure, that my material was manufactured in Asia.

I started my pen-turning career in 2000. At that time I turned quite a few pen barrels from this material. I have recently examined them and have noted that *some* of the barrels have shrunk so that there is a gap of about 15 thou between the end of the plastic barrel and the pen hardware both top and bottom. In this gap you can see an exposed portion (about 15 thou) of the brass tube which was glued into the plastic blank.

I reported this in a thread a few weeks ago, and other people have reported that they also have observed the same phenomenon.
 
35 years ago I set up a resin casting production operation using Water Extended Polyester resin (WEP). We mixed it 50/50 with water, stirred it up real good, catalyzed it with MEKP and poured it into molds for small to medium figurines. In the curing process the resin got hot and most of the water evaporated; most but not all. The castings looked good for a year or two depending on how dry the environment was but eventually they began to shrink and distort. When you cast a doughnut shape and the resin shrinks the hole gets bigger, who knew?

I find the same thing happens to a lesser degree when I mix liquid coloring in with resins that I cast for pen blanks. I made some interesting blanks using nail polish and enamel paint, but after a while they began to shrink and distort. I believe that comes from evaporation of the enamel carrier for the color pigment. I don't see any distortion from castings colored with mica or liquid based pigments that were developed for blending with poly resin.
 
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Gerry, if I read you correctly, there is residual water in the casting.

Commercial acrylics, as I understand it, are cast and heated and made into a sheet under immense (thousands of pounds per inch) of pressure. Sounds like it would "wring out" pretty much all water, if there was ever any present (I believe the base is a petroleum product---"water and oil don't mix").

In any event, could this account for the differences between my experiences and Mal's?? Perhaps "early entries" from Asia had some different characteristics??

Just a guess----

Ed
 
Gerry, if I read you correctly, there is residual water in the casting.

Commercial acrylics, as I understand it, are cast and heated and made into a sheet under immense (thousands of pounds per inch) of pressure. Sounds like it would "wring out" pretty much all water, if there was ever any present (I believe the base is a petroleum product---"water and oil don't mix").

In any event, could this account for the differences between my experiences and Mal's?? Perhaps "early entries" from Asia had some different characteristics??

Just a guess----

Ed

They stopped making the water extended resin years ago because it shrank and distorted as the evaporation continued. The evaporation process was accelerated if the surface of the casting was scraped away and we sanded the bottom of our castings with a belt sander to make them flat.

Cutting and turning a blank opens inner surface areas up and it is possible the oils within can evaporate. Properly cured, and with dry pigments, the long term shrinking could be eliminated.
 
Plastics

When I started turning pens in 1995, one of the exhibitors at the shows we did in Chicago was a guy named "Father Sing". If you look at the history of handmade penmaking (kits), you will find some of the earliest books were authored by this same, Dick Sing.

Seemed unfair for me to walk into the "sport" he created and become competition, so I asked him what he did not like to do. He replied, "Plastics"!

Very few were even attempting plastics at the time, but I made it my specialty. I have turned mostly plastic pens ever since. I have sold thousands and have a couple hundred stored in our "annex" building. They were made before 2008, when I turned my attention to ExoticBlanks and stopped making pens, for sale at shows. NONE of them is distorted in any way I can see. But, I always purchased fairly expensive blanks, most made in Italy. I bought directly from Europe. SOME were purchased from Woodcraft and their predecessors, again all pretty pricey.

So, I have seen other penmakers post that their "plastics" are shrinking. I certainly am not arguing with them, but my experience is different.

Perhaps it depends on the kind of "plastic".

FWIW,
Ed

Hi Ed

Could the acrylics like you use be turn round, have 5/16 ID hole bored into it and then part off pieces that would be like washers or thin washers ?
Like 0.015 or 0.030 ?

Or do you know of a supplier I could buy some ?
 
Mike --

Ed Davidson has done lots with plastics including purchased acrylic rods He is "The Man" for custom yo-yos and has turned a few pens and other things. Do a google search and look at his gallery here under YoYoSpin.

http://www.penturners.org/forum/member.php?u=76

Ed did a DVD on yo-yos several years ago and noted there that one wanted to use cast acrylic rod and not extruded. Different charastics for turning. Ed did some thin stuff.

He has not been hanging around here the last several years, but still turns and sells. Take a look at his web site.
 
.015" is thinner than a potato chip.

A Pen blank, at 5" long will yield dozens, even if you cut them with a standard kerf saw blade. My experience with blanks is limited to pens and other gift items.
I doubt you will see any pattern in a piece that thin, so I don't understand why you would want "pen blanks". However, for under $5, you can buy one and experiment.
That would be the best advice I can offer.
 
Trim rings

.015" is thinner than a potato chip.

A Pen blank, at 5" long will yield dozens, even if you cut them with a standard kerf saw blade. My experience with blanks is limited to pens and other gift items.
I doubt you will see any pattern in a piece that thin, so I don't understand why you would want "pen blanks". However, for under $5, you can buy one and experiment.
That would be the best advice I can offer.


I didn't know if acrylic would shrink or not, and if it didn't is it possible to cut it that thin or buy them pre made ?

When I try to cut them that thin they melt.

I was interested in seeing if I could use acrylic for inlay materials.
I normally only use natural colored woods or bone.
I have a custom order that the customer wants certain colors that natural colored woods will not match the color needed.

So I am seeing what my options on what materials will work or not.
 
When you state it that way, it changes your question.

Yes, you can cut acrylic, incorporate it into your inlay and then turn it down. The thinner it gets, the less the pattern will show. You can partially overcome this by backpainting.

I get several phone calls each week with guys trying to customize for a customer. They want me to tell them exactly HOW to do it. So, here is my "customize speech":
EVERY circumstance is different. I can give you generalities about what SHOULD work and how I would approach your problem. HOWEVER, it is just an APPROACH--you rarely KNOW how something will turn out. SO, you need to purchase products and experiment (using your time). CHARGE THE CUSTOMER FOR THIS!!! The pen is THEIR design, that's great, but you should be making a prototype to confirm that your understanding is correct. CUSTOM pens (or any other CUSTOM product) should not be cheap. You are selling your expertise and YOUR time. CHARGE for it!! I am happy to help, but if I were DOING the project, I would make a prototype to be sure my theories would translate to this product---I encourage you to do the same.

Best of luck, you will learn and that will make you a better craftsman!
 
After thinking about your question, if you need to use the acrylic to separate layers, so you have to reach the thin dimension before turning, I would suggest cutting it about an eighth inch on a bandsaw or tablesaw---use a holding device and a zero clearance sled.

Then get it to the dimension you want by sanding--toward the end you MAY have to sand by hand, to keep heat down. (If you have a thickness sander and some ingenuity, that would probably do the job) I believe you can reach your objective, but it will be slow and painstaking to get it consistent.

Again, good luck!!
 
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