Carbide Tools for Turning Acrylic Blanks? - International Association of Penturners
     International Association of Penturners
Pens for Service Members
 
Support The IAP

Go Back   International Association of Penturners > Community Forums > Penturning
  Forgot Password
Register FAQ Members List Search Today's Posts Mark Forums Read
Penturning General penturning discussions not specifically addressed in one of the specialty forums.


Logged on members can hide ads!

Welcome to penturners.org!

You've found the home of The International Association of Penturners. You are currently viewing our site as a guest, which gives you limited access to view discussions, photos, and library articles.

Consider joining our community today. You'll have full access to all of our content, be able to enter our contests, find local chapters near you, and post your questions and share your experience with our members all over the world.

Membership is completely free!!

If you have any problems with the registration process or your account login, please contact us.

Reply
 
LinkBack Thread Tools Display Modes
Old 05-22-2017, 11:48 AM   #1 (permalink)
 
Join Date: May 2017
Location: North Texas
Posts: 35
Photos: 0

Default Carbide Tools for Turning Acrylic Blanks?

So I just recently got into pen turning. I made a few cool pens from exotic woods and tried my hand on an acrylic blank (I believe it was an inlace acrylester blank). Once I got the blank to round and started turning it down, I noticed my carbide tools were essentially just "chunking out" pieces of blank instead of pulling off in ribbons like it shows in all the videos I watched.

I guess my question is, can you use carbide tools to turn acrylics, or have I unknowingly committed a faux pas? If most people don't have a problem with carbide tools and acrylic blanks, is there something I'm doing wrong? Any tips, etc? I use my round cutter on most things, and this particular blank i tried turning at probably 1000 rpm or so.

I ended up being able to salvage the blank by turning it to shape plus about 1/8" on the radius or so and sanding it down for an hour, but I'm not keen on repeating that process...

Thanks!
thawkins87 is offline   Reply With Quote Top
Old 05-22-2017, 12:04 PM   #2 (permalink)
 
Join Date: Aug 2012
Location: Cincinnati, OH
Posts: 1,503
Photos: 0

Default

Hi Tim,

A couple of thoughts:

1) inlace acryluster gives a lot of people trouble. Seems to be one of the harder acrylics to turn. But the results can be very pretty.
2) I would try a higher rpm - maybe in the 3,000 to 4,000 range
3) carbide works fine on acrylic - but you need to have sharp cutters. Some folks on the IAP replace their blades every couple of pens, others, like me, sharpen the cutter every couple of pens. They are pretty easy to sharpen.
4) glad you could salvage the blank. I have sanded down a few because I was afraid of a chunk or a blow out. But sanding down for an hour seems awfully long. Maybe up your grit of sandpaper (I would start with 150). With acrylics make sure you wet sand (keep the blank and paper wet with plenty of water) rather than dry sand. And maybe up the RPMs as long as you can keep the blank from getting too hot.

Hope that helps.
Dave
Likes: (1)
lyonsacc is offline   Reply With Quote Top
Old 05-22-2017, 12:14 PM   #3 (permalink)
 
mecompco's Avatar
 
Join Date: Apr 2015
Location: Fairfield, Maine
Posts: 1,398
Photos: 8

Default

Dave covered it pretty well! I never slow my lathe down for any pen material--wide open at 3700 all the time (no idea why folks slow them down). IA is probably the worst acrylic to turn--hard and chippy. I use an R2 cutter in my Magical Skew. The Magical Skew's shaft is a hexagon, so it makes it easy to hold at an angle to the work piece, like you would do with a HSS skew. I'm sure you could do the same with your tool. IA prefers to be cut rather than scraped. I am frugal (wife says cheap), so sharpen my cutter with diamond cards.

If you're still getting chipping when your getting near the final diameter, there's no shame in switching to paper. You might, while you are learning acrylics, want to switch to one that is easier to turn (which is pretty much any of them).

Regards,
Michael
mecompco is offline   Reply With Quote Top
Advertisement
Old 05-22-2017, 01:21 PM   #4 (permalink)
 
moke's Avatar
 
Join Date: Dec 2009
Location: Cedar Rapids, Iowa
Posts: 842
Photos: 0

Default

I only turn acrylics for pens and aside from true stone, inlace acrylester is one of the most difficult.....
I totally agree with mecompco, there is no shame in going to sanding earlier than you might ordinarily. Do what you must to get a good product! I might try using the "corner" of the cutter. This is similar to what a metal lathe would be doing....rather than scraping. Scraping "stresses" anything, and chipping is a result. As mentioned, keep your cutter sharp. The diamond file is the best, or just turn it in it's mount.

You can sharpen the cutters many times, except I once mentored a guy who insisted on setting his tool on the lathe and continually knocked it off. Carbide is brittle and chips...turn the cutter head to get rid of the chipped side and always set the tool where it can not be knocked off.

I would recommend picking up a 1" skew chisel, watch some You tube videos on how to use it and practice on 2x4's cut to 1 1/2 square. It takes some practice but the skew is an awesome tool. You can even scrape with it, if you must .... Once you get the hang of it, you will not use your carbide insert tools much.....
All just IMHO.
__________________
Mike aka: Moke

www.hallsphoto.com

Procrastinate Later
--Unknown Author

Last edited by moke; 05-22-2017 at 01:24 PM.
moke is offline   Reply With Quote Top
Old 05-22-2017, 01:47 PM   #5 (permalink)
 
campzeke's Avatar
 
Join Date: Jun 2015
Location: Tampa, FL
Posts: 500
Photos: 5

Default

All good advice in the above posts. I use carbide for all of my pens. Wood, acrylic, antler, and Inlace. I can turn most acrylic blanks in 10 minutes or less. Inlace ... that's another story. I usually turn at 24~2500 RPM... it works for me. When turning Inlace, I use very light cuts and will often sand the corners off on a belt sander before turning. I will almost always spend 2 to 3 times longer on an inlace blank than almost any other type. It's worth it in the end but it does require a little more patience in the process. The same is true of the Stars and stripes blanks many vendors sell.

As a new turner, I would recommend staying away from Inlace until you are more comfortable with some of the other acrylics out there. Work on your fit and finish first. Focus on smooth, tight joints where the blank meets the kit hardware. Work on your sanding and polishing procedure then apply what you learned and ease back into Inlace.

Bottom line, don't get discouraged and let's see some photos of those beautiful pens you are creating!
__________________
Rick - Tampa, FL
campzeke is offline   Reply With Quote Top
Old 05-22-2017, 02:16 PM   #6 (permalink)
 
Join Date: May 2017
Location: North Texas
Posts: 35
Photos: 0

Default

Awesome - thank y'all so much for the tips/advice. I suppose it was just a bit unlucky that I grabbed one of the harder materials to work with the first time around; I'm glad I asked the question or else I would have assumed that all acrylics were as difficult!
thawkins87 is offline   Reply With Quote Top
Old 05-22-2017, 02:47 PM   #7 (permalink)
New Member Advocate
 
Edgar's Avatar
 
Join Date: Feb 2013
Location: Alvin, TX 77511
Posts: 4,981
Photos: 23

Default

All great advice - I can't really add much except to suggest that you try an R2 cutter. I find it easier to control and get the contours that I want on pens than a round cutter. I use my round cutter for some of my bottle stoppers & other spindle shaping, but when I just want a straight or slightly contoured shape, an R2 works best for me.

I also agree with Mike, cant the R2 cutter about 30˚ or so rather than presenting it straight on. I just have a regular square bar on mine, but I have no problem canting it to and holding a steady angle with it. A hexagonal bar like the Magic Skew does make it easier though.

Definitely high speed & sharp tools. I generally turn pens around 3000 RPM.
__________________
Eat pecans - 10,000,000 squirrels can't be wrong.
Edgar is offline   Reply With Quote Top
Old 05-22-2017, 03:12 PM   #8 (permalink)
 
Magicbob's Avatar
 
Join Date: Oct 2012
Location: Akron, OH
Posts: 1,209
Photos: 6

Default

inlace acrylester is the reason I developed the Magical Skew.
Cutting vs scraping, it makes a big difference.
__________________
Inventor of the Magical Skew

M
idwest Penturners Gathering 2018
Date: May 18-20
Comfort Inn & Suites 5 Park Center Drive
Wadsworth, Ohio, OH 44281
Go here: Facebook Page to read about past MPGs


Likes: (2)
Magicbob is offline   Reply With Quote Top
Old 05-23-2017, 01:17 AM   #9 (permalink)
 
qquake's Avatar
 
Join Date: Feb 2004
Location: Northern California
Posts: 1,412
Photos: 1

Default

I hate inlace acrylester, and rarely turn it. When I do, I always use sandpaper for final shaping, starting with 100 grit. This money blank is either inlace acrylester, or turns just like it, and I hated it. But my friend was set on a pen with it, so I persevered.
Attached Thumbnails
027.jpg   031.jpg   032.jpg   037.jpg   043.jpg  

__________________
Jim Lane
Penturner since 1999
qquake is offline   Reply With Quote Top
Old 05-23-2017, 01:36 AM   #10 (permalink)
 
Join Date: Mar 2016
Location: Marietta, GA
Posts: 657
Photos: 59

Default

I turn a lot of IA. I use a 3/4 inch Sorby spindle gouge and my round carbide. In some instances, I turned the corner round using a mill file. I also stop a little proud of the final dimension and take the rest of the way with Abranet. I usually start with 80 and go to 600, then I wet sand it using 500 and 1000 grit then finally I switch to MM and go from 1500 to 12000. That put a finish on it that can stand on it's own, however, I use sometype of plastic polish to complete the process. Now that I have a R2 carbide I will be using it to do some of the final turning.
eharri446 is offline   Reply With Quote Top
Related Content
Logged on members can hide ads
Reply

Bookmarks

Tags
acrylic , carbide tools

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


All times are GMT -5. The time now is 02:40 PM.

Powered by vBulletin® Version 3.7.6
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0

Content Copyright © 2003-2016 by Penturners.org, LLC; All Rights Reserved
Terms Of Service   Acceptable Use Policy