Acrylics newbie and its driving me nuts!

[ColoradoHermit]

I've been turning pens since March of last year (2008) but only in wood. I got out sold at a craft show a month ago by some one that only had Trident or Polaris style (Same kit different place ordered from) pens done in only acrylics. He sold 20 pens out of about 40 that he had on display and I sold one click pen made from zebra wood. And I had over 150 pens in 27 different woods and 12 different styles to choose from priced from $20 to $35. To say that after the show I was standing there saying "WT* is wrong here?" is an understatement! So I thought that I should try making some acrylic pens in spite of the high cost of the blanks. And they have been driving me nuts!
What does it take to get acrylic to turn? It doesn't matter what tool I use or what speed I run it. If I try to get anything more than a very light skimming cut all I get is a lot of tool chatter and deep gouges with a lot of little holes in the bottom of the gouged groves. The stink of turning it was bad enough, but what does it take to get the stuff to cut?
This is really bugging me because I was a machinist for over 20 years and I've machined all sorts of parts out of all sorts of materials over the years. I should be able to figure this one out but I haven't been able to and I'm about to chuck the whole bunch of acrylic blocks in the cook stove!
Anybody have any suggestions out there? Or is this just one of those things, like the stink, of turning acrylics? Can the stuff only be turned with light skimming cuts or is there a quicker way to turn it?

 

[CaptG]

Scarey sharp tools, fast rpm, and light cuts. This works well for me.

 

[seawolf]

Some will sand away the corners befor turning. I use a 3/4 roughing gouge and follow up with a skew. Fastest speed on the lathe.
Mark

 

[RAdams]

I use a spindle gouge, and a round scraper. As well as the fast speed on the lathe.

I like to "rough" the blank down with a spindle gouge, and then use the scraper. Pay careful attention to the edges. As long as the holes don't get too deep, it doesnt matter. make sense?

In other words, carefully turn each end down with light cuts so as not to chip the acrylic to near final size. use the spindle gouge to rough turn the center area. If it takes out too many pieces, then use lighter cuts. the deeper in the blank you go, the lighter the cuts should be. get the center area close to final size, and then use the round scraper to smooth it all out.

I have found that if you file the top edge of the scraper after sharpening, it works much better for the plastics.

P.S. You can buy a gallon of Poly Resin for around $50 delivered to your door. Some color, and a little bit of PVC pipe and you can make your first batch. You will get over 60 two ounce pen blanks for your initial $100 investment. It gets even cheaper if you buy the PR in 5 gallon buckets! I am making approx 300 blanks, and the cost is about $1.06 per blank.

 

[mickr]

knock the edges off with a sanding disc/belt..then use a skew...

 

[Chasper]

Sharp tools, light touch, high speed, round off the ends early and often. Use the skew. Not all resins are equal, some are brittle and chippy, others are soft and hard to get a ribbon started with anything but a scraper.

 

[Daniel]

A lot depends on what acrylic you are using as well. You did not mention what you have but for Acrylester has been the worst. More like turning glass than plastic. Celluloid was the first really good one I ever turned. I just turned a bunch of acrylics from woodpenpro.com and they where all very nice to turn. Also the woodpenpro blanks where very good on the opacity issue. only a couple of them started showing signs of needed the inside painted. Basically I am slowely making a mental list of what acrylics to use and which ones not to.

 

[rherrell]

I'll second Daniels WOODPENPRO recommendation. Be sure to get the round ones and save yourself alot of heartache!:wink:

 

[randyrls]

Dan; Take a look at these two videos by Barry Gross. Note that the skew is making a shear cut, not a scrape.

1st part is prep:
http://www.youtube.com/watch?v=MDrR7xocrvQ

2nd part is turning and finishing:
http://www.youtube.com/watch?v=FzYu_rEmsPc

 

[arjudy]

1/2 inch spindle gouge to rough out to round and then I use a oval skew on its edge as a scraper to get to the finished shape. Did one last evening and spent maybe 20 minutes from start of turning to end of polishing with MM and I also use the lathe at full speed for all steps. Hope this helps you.

 

[maxwell_smart007]

Doesn't matter what tools you use, they have to be VERY sharp for acrylics. Woods are much more forgiving, in that they tend to cut no matter how you tool them, and can be sanded smooth easily...

 

[kenlicciardello]

Lots of good advise here. I agree with scary sharp, high speed and be very careful with inlace acrylester. I mainly use gouge or scraper. MM then plastic polish. Can't beat wood pen pro and exoticblanks.com for blanks

 

[ColoradoHermit]

Thanks for all the advice and suggestions. Where I got my acrylic blanks was from WoodnWhimsies.com. That's where I get most of my kits from and I get most of my wood blanks from westpennhardwoods.com, exoticwood.biz, and forgottenwoods.net. These places have the best prices and selections that I've been able to find.

 

[Spats139]

I use a skew from start to finish, round blank or square, wood or acrylic; and I am very happy with the results. I'm sure it's no better, and no worse, than the other suggestions, it's just the way I do it. I'm usually in the 1500-1800 speed range with acrylic, but as others have indicated here, that's also a personal preference with lots of wiggle room.

So, which ever way works best for you, is the way to go for you; just don't give up. One of these times you're going to have your "eureka" moment, and you're going to nail it. There will be no stopping you then!

 

[ed4copies]

One trick is NOTICING when you are succeeding.

You don't take off chips with every pass, or the material would be GONE very quickly. So, when you are not experiencing a FAILURE, you are experiencing success. LOOK to see what you are doing THEN!! Then, do more of it.

Turning is not about you doing it MY way. It's about you learning to do it a way that works for you. Some day, you may see me demonstrate and say, WOW, is that easy!!!! Why didn't I do that??

However, if you have been making pens successfully, a new technique is just an improvement!

 

[bobleibo]

- like everyone said....very, very, very sharp tools
- patience, a little bit at a time, 3 minutes of hurry will destroy 20 minutes of prep
- I turn my gouge way up on its' edge and take little bits at a time until it's rounded
then it just peels off in a stream
- I raise the rest a bit higher than with wood and level my tool or point it down just a
hair.
- patience
- I turn the ends inward from the outside to avoid chipping them especially with brittle
blanks, until I get it pretty rounded out
- patience
- did we mention patience
- just in case I forgot, patience
- oh yeah, take it slow!

Lots of great tips here......use a few and find your own style

Good luck.....if you don't blow a few out, you are way better then me, but that's no great accomplishment....

Cheers

 

[TellicoTurning]

I guess I will just echo every one else... a really sharp skew, high speed and take your time.. it takes about 2 or 3 minutes longer to do an acrylic than it does a wood, but if you're in same boat as me.. you got more time than money anyway.

 

[gothycdesigns]

Last year I bought a Spindlemaster tool. Would this work ok for the scraping or skew like work? I was curious. I was just having the same problem turning acrylic and searched, and found this thread so it covers my questions. Just thought to ask about the Spindlemaster.

ThX