acrylic finishing help

[Perl]

Ok new guy here needs a little advice on finishing acrylic. Though working with acrylic would be easier than wood, wow was I wrong! My first one went well, second one exploded in my face!! third one chipped really bad just before time to start finishing down by the nib. Next one has what appears to have pretty deep sanding marks. I only used mm after I was through shaping it. I assume cross sanding on acrylic is wrong??? Do i need to just keep sanding w/ the mm pads. Is CA or wax recommended/needed?

 

[TBCbushings]

I did some pens on video you can look at....Click on the ustream link in my sig line.
Hope this helps,
Brian

 

[alphageek]

First, there is MANY acrylics! Exactly which one you are using might explain some of them..

Next what tools are you using and what speed? A skew is the best tool (once you get used to it) and turn as fast as you can be comfortable with.

Then what grits of sandpaper? If your seeing deep sanding marks that may mean you are jumping grits too far.

No CA or wax needed.. just sand/polish.... Buffing would be another big suggestion, but there is other things to learn first.

Search youtube for ed4copies.. he has a couple of good videos on turning acrylic (and I'll bet he will be here to give advise shortly )

 

[Whaler]

Ok new guy here needs a little advice on finishing acrylic. Though working with acrylic would be easier than wood, wow was I wrong! My first one went well, second one exploded in my face!! third one chipped really bad just before time to start finishing down by the nib. Next one has what appears to have pretty deep sanding marks. I only used mm after I was through shaping it. I assume cross sanding on acrylic is wrong??? Do i need to just keep sanding w/ the mm pads. Is CA or wax recommended/needed?

You will probably get a lot of different opinions on this. So here is mine.
When turning use sharp tools and light cuts.
I have changed my sanding methods but I started sanding dry through 400 grit while the lathe was turning then stopping the lathe and sanding length wise between grits and then MM wet through 12000 and then a plastic polish. Now I sand through 320 and do the rest on the Beale buffing system and top it off with Ren wax.

 

[ed4copies]

First, there is MANY acrylics! Exactly which one you are using might explain some of them..

Next what tools are you using and what speed? A skew is the best tool (once you get used to it) and turn as fast as you can be comfortable with.

Then what grits of sandpaper? If your seeing deep sanding marks that may mean you are jumping grits too far.

No CA or wax needed.. just sand/polish.... Buffing would be another big suggestion, but there is other things to learn first.

Search youtube for ed4copies.. he has a couple of good videos on turning acrylic (and I'll bet he will be here to give advise shortly )

My advice? Follow Dean's advice and post any questions. Be happy to try to help.

 

[Perl]

Thanks for the info so far. To answer a few of your questions, I only wet sanded w/mm pads1500 - 12000 all 9 grits. The blank was a Woodriver bought at Woodcraft "lava". I have no idea what is actually in it. Once I got the blank close to where I wanted it I only used the skew. Can i fill in chips with CA? is faster turning speed usually preferred?

 

[jttheclockman]

Oh how many times I read people having problems turning acrylic and then people tell them to use a skew and to sharpen it or any other tool. These are true words and will get you through any acrylics.

But let me demystify something here. It seems there is this taboo theory is is a bad thing to turn a skew on its side and use as a scraper. Well to --- with that notion and just do it and you will see a tremendous difference and no catches or skate marks. In fact that is how the Spindlemaster was born. It is a well known tool for turning pens. If you are having troubles turning acrylics use the skew as a scraper. First turn the blank close to whatever shape you need with a tool of your choice and to finish turning use the skew as a scaper but it will dull faster this way but will get the job done and no need for sandpaper again on acrylics. Go right to MM. That is my 2¢

 

[ed4copies]

Hey JT,
Why not just use a scraper, then?

Skews can be sharpened in dozens of different profiles. While you may have one that contacts the blank without catching while using it horizontally, the next guy may have the conventional straight line edge, which is very likely to catch in the horizontal orientation.

If you want to scrape, use a scraper, they are "beefier" and will not have as much vibration. And they are designed not to "catch" in the horizontal orientation.

As always, what WORKS for YOU is RIGHT for YOU. But, when telling others, try to anticipate the possible "disasters".

 

[jttheclockman]

Hey JT,
Why not just use a scraper, then?

Skews can be sharpened in dozens of different profiles. While you may have one that contacts the blank without catching while using it horizontally, the next guy may have the conventional straight line edge, which is very likely to catch in the horizontal orientation.

If you want to scrape, use a scraper, they are "beefier" and will not have as much vibration. And they are designed not to "catch" in the horizontal orientation.

As always, what WORKS for YOU is RIGHT for YOU. But, when telling others, try to anticipate the possible "disasters".

Ed my skew is as straight as an arrow across and never ever had a catch using it as a scraper. Yes a scraper can be used. Not everyone has a scraper which is not a tool used much for pen turning. I agree what works for one does not work for all. Just throwing out a possibility because I have read this on this site about using a skew as a scraper is frowned upon. So it falls in the catagory if it works for me I will continue to use it. If you are getting vibration turning a pen blank you seriously need to look into getting the lathe looked at or sharpen the tool.

If you had to include every disaster possible with anything we do the page would be quite long. As with any woodworking tool understand the tool and be aware for anything and use safe practices.

 

[Mac]

I like what Ed said.

 

[ed4copies]

I like what Ed said.

Thank you.

In my new position at Exotics, I talk with quite a few "new turners". I am learning that what I consider rudimentary is completely baffling to some of our members.

So, FOR ME, simple instructions have become the norm.

I have not EVER had a quarrel with those who do things differently from my way, if it WORKS for YOU, DO IT!!!!

 

[jttheclockman]

I like what John T said.:biggrin:

 

[ROOKIETURNER]

My steps that never fail:

1) Round using a rough gouge. Use the edge to the middle. ONLY USE LIGHT TOUCH!!!
2) Shape with a round scraper. Use the edge to the middle. ONLY USE LIGHT TOUCH!!!
3) Use your skew like a scraper. You can even out the shape using the straight edge. The skew has to be SHARP!!!
4) ONLY WET SAND!!! Heat is your enemy. 1500-longest (about 30-40 seconds); 1800 about the same; then decrease the time as you move toward 12000.

I mix a little Brasso in with my water that I use when sanding. It is a very mile abrasive.

I use a three step polishing method. No need for a buffing wheel. So far I can get my acrylics and ca finishes mirror like with out wax or a wheel. I use microfiber clothes on the first two steps and then 100% cotton t-shirt for the final polish.

Step one: Head Light Lense Restorer (Macguires)
Step two: Macguires plastic polish
Step three: Huts plastic polish

Each are less abrasive and will give you a mirror like finish every time!

Have fun! Experiment on your own and let us know how it goes! POST PICTURES!!!

Rob

 

[ldb2000]

A properly used Skew is a "Cutting" tool NOT a "Scraping" tool . When PROPERLY used it will not catch or cause chip out but when used as a scraper the chances of a catch AND chip out increase dramatically . The skew is NOT a scraper and really shouldn't be used as one , the cutting edge is much too thin to give proper support which causes vibration and is why it is more prone to catch and chip out .
A properly sharpened scraper will have a slightly negative rake angle on the cutting edge making it less aggressive then a flat cutting edge which makes it perfect for brittle acrylics and the thickness of the cutting edge supports the cut and prevents vibrations which is a major reason for catches . The sharp pointy edges on a skew can also cause catches and dig ins that cause chip out .
A properly sharpened round nose scraper is a tool that every penmaker should have in their tool boxes , and the PROPER use of the skew is something ALL penmakers should learn . When I first started turning I blew up almost every acrylic blank I tried to turn , then I did allot of research and learned the proper way to use a skew , I now can routinely turn Inlace Acrylester and the hardest Tru-Stones without any chip out . Take the time to learn how to properly use a skew , it will become your #1 turning tool for any material and a must for brittle materials like some acrylics and Tru-Stones .

 

[Mac]

I like what Butch said.
Hey this one don't rhyme.
But, I still like what Butch said

 

[jttheclockman]

Let me clarify something here because I see this is heading for a pile-on thread about the use of a skew. And this is what I meant about the frowning of doing this method.

Now this is my technique and you can do as you see fit and I only threw it out there as a possible answer to cleaning up the acrylic cuts. There is nothing wrong with using a skew to fine tune a shape on a blank. Yes learn the proper use of a skew. It is not meant to use in a scraping fashion from start to finish but to sweeten a blank there is nothing wrong with laying the skew horizontal. You can get a catch with any tool if not properly used. It is done by many pen turners.

Listen to Ed and Butch and learn the proper use of the skew. It is one of the best tools in the arsenal.

 

[dhammis]

I've only been turning for about a year but this is the method that I've used for acrylics and corian that has suited me well.

I got a Mini Rougher from Easy Wood Tools. It's similar to the Woodchuck Pen Pro that is sold here. The carbide tips make easy work of rounding the blank. It's a lot of passes taking off a little material at a time so you don't get those skips, chips, and heat generated, but the sharp tool makes those passes go fast. After the excess is removed I switch to the skew. Before I touch the skew to the material I hone it on my stones so it's sharp. Light passes using the skew as it is intended to get the shape I desire, then when it's nearly done I'll turn the skew flat and take one or two passes to smooth it out.

After validating the measurements with the calipers I start to sand/polish. I wet sand using water with a couple of drops of dish soap in it. I sand 150, 240, 320, 400, 600, 1000, then switch to MM 1500-12000. I sand lengthwise by hand between grits and use a paper towel to wipe the blank between each grit as well so there is no residue left. Then I'll use the HUT Ultra Gloss Plastic Polish. I take the barrel(s) off and put my buffing wheel on and then use white diamond to buff.

The result is usually a nice deep shine.

Watch the videos by Barry Gross on Youtube regarding turning acrylics. There are a few others that have been mentioned already as well in this thread.

Good luck!

 

[hunter-27]

I'll probably take over getting piled on here but heck, I can handle it.:beat-up: Skipping the tooling part.................Sanding. I hear everyone saying wet sand, wet sand, wet sand. I'm not saying it is wrong but.......I don't like water in my shop as a general rule. I have turned numerous "acrylics" (all kinds), no matter the type once I get done tooling. I start with 400 grit paper (dry) Since plastic doesn't really have "graining" in the same sense as wood I see no difference in sanding lethwise or not but I do both out of habit.(I'm a wooden pen turner mostly) After I use the 400 I go to MM through all the sheets(dry) After I am satisfied(sometimes I back step if I see a flaw I don't like). I will go to brasso(if it is good enough to polish military brass it is good enough for my pens) I do this lathe on, shut it off, a buff with clean cloth then do the brasso again. Next is buff with a new clean cloth followed by ren wax(just cuz I like it). Now I'm not saying if you look at uder a microscope you can't see flaws but I am saying I've never sold a pen to anyone carrying a microscope around with them. It is MY procedure take it or leave it but don't bash it until you see ME do it, cuz I like it. Now let the Pile switch from the use of a skew to the use of sandpaper.:wink:

 

[flyfisher117]

Im a Green horn here and only turned my first pen a few months ago and have since made 4 acrylic pens and havent had an issue finish them, to the naked eye theres no scratches maybe there are with a jewel loop but most peoples eyes dont magnify that well.

My steps that have worked and i turn the same exact acrylics that you are using.

#1 round with a smaller roughing gouge.
#2 get the basic shape i want with a rounded scraper
#3 if i want more shapes and need to be more detailed i get a smaller rounded scraper
#4 dry sand lightly not creating heat with 600 grit sand paper.
#5 wet sand with 600-1200 grit micro mesh pads
#6 Hut or one step plastic polish

im new enough to turning im probably doing it all wrong, but hey friends and family are all amazed at the pens so thats all that matters to me.

 

[dhammis]

I only wet sand acrylics and corian. It keeps the blank cooler. I put a towel down on the lathe bed to prevent water from getting on the lathe. I cross sand because wood or not, you are still getting the vertical sanding marks.

Of course, this just works for me. Some wet sand up to 600, then dry MM. Some dry sand up to 600, then wet MM. It's all whatever works best for you.

 

[PenMan1]

Ok, I toss in another opinion. Most all of my pens are made from alternative materials. Since I put away the HSS tools and went exclusively to carbide tools, I RARELY see scratch marks, even BEFORE sanding.

After the carbide, I wet sand with Abranet and brasso, from 320 to 600. Then, I change to MM and slurry water to 12,000. After the 12,000, I use the magnifying glass to find any remaining scratches, THEN over to the White Diamond buff wheel.

After the buff wheel, back to lathe with wet MM starting at 4,000 (IMHO, the white diamond take the finish back to about 4,000). Finish to 12,000 THEN one round of Novus 2, followed bt two cycles of Plastx. You can see yourself in a black finish with no scratches visible with a magnifying glass.

This sounds involved, but the whole process takes about 15 minutes.

 

[PenMan1]

Just two questions.
1. Do you turn with the long point of the skew pointing toward the ceiling, or toward the floor?
2. Are you right handed or left handed and which hand is closest to the tool rest when you turn?

 

[ldb2000]

In answer to your questions Andy
1 - Yes
2 - Both

:biggrin::biggrin::biggrin:

 

[PenMan1]

In answer to your questions Andy
1 - Yes
2 - Both

:biggrin::biggrin::biggrin:

I was afraid of that answer. Put down the skew, before you hurt yourself.


#1 was an either/ or answer.

How's your weather?

 

[ldb2000]

Sorry Andy I couldn't resist . In most cases I use the skew with the point down but depending on the material I will use it point up for a less aggressive cut . As for which hand is closer to the rest I switch hands and my control hand is always furthest from the rest .
The weather was good today but we have an Ice storm coming for Tues into Wed . Just what we needed , this has been one heck of a winter so far .... and there's still 2 months to go !!!