# plexi drying



## flyingmelon (Aug 29, 2008)

How long do you let your plexi coatings dry before finish sanding? I have been playing with this finish for a couple of days now and seem to be breaking (?) the finish off when I start to sand. Am I not putting it on correctly, or letting it dry enough, or am just experiencing the upslope of the learning curve? I am sanding to 8000 then putting on several coats of the plexi (about med CA thick) then starting back at the beginning of the MM set. It seems to happen somewhere between the third and fourth pad. I like the way it looks and can see the potential for it being a great finish but am just not getting it.


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## thewishman (Aug 29, 2008)

Here is a run through on my finish:

After the plexi is dissolved I pour it into a clear
condiment bottle (Wal-Mart $.79) but any container 
that allows you do dispense a drop will work - though 
you should check to make sure the acetone won't 
dissolve the bottle) and add a bit more
acetone until the solution is a bit thicker than thin
CA glue. I check mine by putting a drop on a paper 
towel, the drop should retain its shape for just a second 
before being absorbed.You can experiment to get your ideal
viscosity, some people like the solution much thicker
than mine. 

I sand my blanks to 400 grit and then remove all of
the dust from them. I lay newspaper across my lathe,
under the mandrel and set the lathe at 1800 rpm, I
also have a spacer bushing at each end of the mandrel.
I put a small bag from a pen kit and put it over my
index finger, fold a 1/2 paper towel to about 1/2 inch
wide. 

Put a couple of drops of solution on the paper towel
and run it under the spinning blanks. Start applying
just a little pressure on the bushing set before the
blank and make a smooth motion through the bushing at
the opposite end (the motion should take about as long
as it takes to say "motion.") Then put another drop on
the towel and go the opposite way, use enough solution
so that the towel is transferring the solution to the
blanks through the whole range. I put 40 coats on
in about 3 to 4 minutes (drip, slide, drip, slide) it
dries quickly enough that the  time it takes to add a
drip is all the time you need to wait. (Thicker
solutions mean slower drying time.) 

After the coats have been applied, I let the lathe
spin for 2-3 minutes and then start wet sanding (just water)
 with Micro Mesh. Be careful with the 1500 grit, with my
first few tries I removed most of the plexi with that
one. Just a few seconds with moderate pressure is
enough for each grit, and dry off the blank between
grits to remove the slurry. The MM work is done at the
same 1800 rpms. After some practice the whole
procedure from the first drop to removing the polished
blanks takes about 6 - 7 minutes.

I turn the lathe off and use a utility knife to score
the plexi just a bout 1/16 - 1/8 inch from the end of
the blank, be careful to do it lightly so you don't
cut into your bushings. I learned the hard way to
score, since the finish is built up on the bushings as
well as the  blanks. I then remove the blanks and trim
any extra finish off the ends. I put a small piece of 400
grit sandpaper on the lathe bed and rub the finished ends 
of the barrels (holding them perpendicular to the bed) to clean 
off any extra finish that might extend from the ends.

Good luck with this, the Holy Grail* of finishes - cheap, durable (probably the MOST durable finish) shiny and quick.


*Now you must bring us a SHRUBBERY!


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## RMB (Aug 30, 2008)

Wow Chris, that sounds like a great finish, thanks for the detailed procedure! I've had to abandon my CA finish (right when I was getting good at it too!) because I moved my penturning operations to a tiny shop and the fumes are just too much. I'm experimenting with laquer dipping, which I like so far, but I'm looking for new finishes. 

Can you give me a bit more info on the Plexi? is it just regular plexiglass from the BORG disolved in Acetone? are there a lot of fumes? Is there an article about it somewhere?


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## thewishman (Aug 30, 2008)

I got my plexi at Lowes from their scrap bin - 2'x3' for $1.00 - enough for at least 1500 pens. Acetone fumes are not something you want in an enclosed space. You'll at least want an open door or window with fresh air.

My first try at dissolving the plexi didn't work - I had the wrong kind of material. It melted but didn't go into solution - just stayed in an amorphous blob. When I got the right stuff it started dissolving right away. My solution is milky, but dries perfectly clear. I have been told that milky is unusual, most people's solution is clear.

My mother jar of solution is a Mason jar and I just shake it gently every once in a while, every few days or weeks. The rubber seal in the lid does dissolve, so pick out those pieces when you pour into the dispenser. I tried using a new paint can, but the interior was painted and came off in the solution, and it is hard to pour cleanly from a paint can into a smaller vessel.

By the way, Micro Mesh was invented to polish Plexiglas - airplane windshields - so using the MM helps it fulfill its destiny.


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## hewunch (Aug 30, 2008)

OK thewishman did a great job talking about his method. I would add a few things (and remember, it is all up to you and what works for you. My solution is between thin and med CA. I use a rubber finger cover (used for counting money) found at any office supply store. The big problems I had at the beginning were pressure and heat. I basically wick the solution on to the blank. (Oh and I sand through 1500 first and wipe with DNA) Then do a sealer coat of thin CA. I do 5 wipes, stop the lathe, look for bubbles then start and do 5 more. I usually do between 20 and 25 coats stopping every 5. Now when sanding, wet at a low speed. Make sure when you finish the first grit of MM (1500) you have no shiny spots (those are low spots) then move through the rest and you have your finish.


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## thewishman (Aug 30, 2008)

Sounds good, Hans. By the way, the Designer pen on your home page is gorgeous.

Terry Miller, who was the first person I know to do the plexi finish, does it with an even thicker solution and fewer coats. Figure out what works for you. If you like it, share your method with others - that way we can all learn together. (Gee whiz, now I think I hear someone singing Kum Ba Ya. Sorry to get all sappy there.)


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## RMB (Aug 31, 2008)

Thanks guys, I'll have to give that a try.


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## JimB (Aug 31, 2008)

This sounds like something I might want to try. How much acetone do you use to disolve the plexi?


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## hewunch (Aug 31, 2008)

thewishman said:


> Sounds good, Hans. By the way, the Designer pen on your home page is gorgeous.



Thanks! That was my first Afzelia Xylay pen. Funny that my last name Wunch means "to wish" in German. 

I would think you could dip them like some people do lacquer too. But I have never tried.


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## hewunch (Aug 31, 2008)

JimB said:


> This sounds like something I might want to try. How much acetone do you use to disolve the plexi?



Cover the plexi in the bottom of the can/jar. Then wait for it to dissolve. Add more if you have an "iceberg" sticking out


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## redfishsc (Sep 1, 2008)

OK, I have the shrubbery. Do you want me to place it beside the other one, slightly elevated, so as to get that 2-level look?



How does the plexi finish stand up to hand sweat and crud? Does it hold the glossy sheen or does it, over time, reduce a bit to a more satin look?


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## thewishman (Sep 1, 2008)

redfishsc said:


> OK, I have the shrubbery. Do you want me to place it beside the other one, slightly elevated, so as to get that 2-level look?



Now you must cut down the mightiest tree in the forest, with...








.
.
.



.
.
.




A herring!!!


Yes, it holds up well with sweat and crud. Carrying a dark pen as a courier, with 15+ people signing a day and lots of other writing and dropping, the sheen was slightly reduced. No nicks or scratches, and still shiny - not fresh off the lathe shiny, but you could only tell by directly comparing a freshly finished pen.


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## handplane (Sep 3, 2008)

As for toughness, if it is anything like the aircraft windows I deal with daily it should be almost indestructible.  We just changed a couple so I'm going to see if this stuff will melt in the acetone.  I know that polycarbonate just turns to a blob.  Acrylic and abs melt very nicely.  This may be the finish I've been looking for.

One question, will it work on alumilite or pr cast blanks?  I have some of Eugenes Cancun blanks and don't want to ruin them.


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## MobilMan (Sep 3, 2008)

flyingmelon.  Could it be you're sanding it too smooth?  Try stopping at 400-600 grit before the first coat.  It will have more to grip on a coarser surface.


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