jeffreybrown18
Member
I have started turning acrylic. But i have had some come apart when I'm turning them. I use a carbide tool. I tried turning slow then fast, used water to keep it cool. does anyone have some advice to help same me some money.
Acrylic Blanks coming apart
- Thread starter jeffreybrown18
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Justturnin
Member
When you say coming apart do you mean the tube is releasing? If so how are you glueing the tubes in?
jeffreybrown18
Member
They are exploding on me. and i glue them in with CA.
Monty
Group Buy Coordinator
A carbide tool cuts aggressively and my be catching the acrylic causing it to explode on you.
edstreet
Member
Mind posting a shot of the shavings and the blank? Reason being not all blanks are the same, you can learn a ton of things just from the shavings and not only could it be the chisel itself but it technique could also be to blame.
alphageek
Former Moderator
A couple of things that I think of whenever someone new posts this.
1) how fast? I find slow to be really bad - you are more prone to to much grab if slow. I turn pens at full speed - but no matter what speed, you must get comfortable with the tools
2) LIGHT touch, especially with the carbide tools as they are sharp, but not very forgiving in other ways as they tend to be like a scraper, not a tool with a bevel to ride.
3) what "acrylic"? Some are much more forgiving than others.
1) how fast? I find slow to be really bad - you are more prone to to much grab if slow. I turn pens at full speed - but no matter what speed, you must get comfortable with the tools
2) LIGHT touch, especially with the carbide tools as they are sharp, but not very forgiving in other ways as they tend to be like a scraper, not a tool with a bevel to ride.
3) what "acrylic"? Some are much more forgiving than others.
Justturnin
Member
I would also add that gluing w/ Epoxy would be a better solution.
wood-of-1kind
Member
Which carbide (shape) insert are you using? The SQUARE or ROUND shape?
The round shape is less "aggressive" and makes turning 'brittle' acrylic less of a challenge. Speed (RPM) is also a contibuting factor to the ability of material removal.
If you reveal a little more of detail as how you are turning then help will be forthcoming.
The round shape is less "aggressive" and makes turning 'brittle' acrylic less of a challenge. Speed (RPM) is also a contibuting factor to the ability of material removal.
If you reveal a little more of detail as how you are turning then help will be forthcoming.
healeydays
Member
This question leads to the possibility of a great video. Anyone want to put a video together on how to best use carbide tools with acrylic? I know I just picked up the tools and ran with it, but can always learn a few tricks from the masters...
If the blank explodes, the problem is in your tool handling. They don't break apart because of the glue, they break because the tool is applied to aggressively.
The only other possibility is drilling, if you are too aggressive in drilling the blank can crack and then blow up in turning.
What you can do is to turn a bunch of blanks and get the feel for how to handle the tools. Turning is an acquired skill, you have to work at it to learn how.
The only other possibility is drilling, if you are too aggressive in drilling the blank can crack and then blow up in turning.
What you can do is to turn a bunch of blanks and get the feel for how to handle the tools. Turning is an acquired skill, you have to work at it to learn how.
alparent
Member
I use carbide tools and love them. I run my lathe at full speed but turn down the black slowly.
I use the tool almost like a skew. Kinda. I ride that little bevel.
Make sure you don't shatter the acrylic. When you start with a square blank you will get shattering.....but as the blank rounds out...you should start getting shavings and not shattering. You should get nice strands instead of shattered pieces. If not ... you are to aggressive.
I use the radius insert. I found the round one would dig in to much.
I don't really cut the face of the blank (like spindle work) but more from side to side (like shaping a bowl). Sorry, I know my description is crappy but I don't really know how to explain this.
I can now turn an acrylic blank in about 5 min.
I use the tool almost like a skew. Kinda. I ride that little bevel.
Make sure you don't shatter the acrylic. When you start with a square blank you will get shattering.....but as the blank rounds out...you should start getting shavings and not shattering. You should get nice strands instead of shattered pieces. If not ... you are to aggressive.
I use the radius insert. I found the round one would dig in to much.
I don't really cut the face of the blank (like spindle work) but more from side to side (like shaping a bowl). Sorry, I know my description is crappy but I don't really know how to explain this.
I can now turn an acrylic blank in about 5 min.
chris63
Member
this happens occasionally on me also, i think it might be air bubbles or defective acrylic. just a thought
mhbeauford
Member
I use both carbide and HS Steel on acrylic. Negative rake helps. Set the rest a little higher and tip the tool down a little to create about 10 deg of negative rake. This will prevent a lot a catches and cutting too aggressively with the carbide. I turn fast and take light cuts.
ed4copies
Local Chapter Manager
It's kinda funny, when you think about this!!
We started using carbide insert tools because it was too much work to learn to use conventional skews and gouges. NOW, we need further instruction on carbide tools.
Why not use a gouge or skew? If you use THEM correctly you can turn down a square acrylic blank in a very few passes. I know of NO way to do that with a carbide insert tool.
"The right tool for the job"??? Carbide works GREAT on bone and other very dense material.
FWIW,
Ed
We started using carbide insert tools because it was too much work to learn to use conventional skews and gouges. NOW, we need further instruction on carbide tools.
Why not use a gouge or skew? If you use THEM correctly you can turn down a square acrylic blank in a very few passes. I know of NO way to do that with a carbide insert tool.
"The right tool for the job"??? Carbide works GREAT on bone and other very dense material.
FWIW,
Ed
Ed, can you please explain how you do it? I received instructions from craft supplies (I think) that showed using a scraper. I would like to be able to turn them a lot quicker, but I'm not real comfortable with a skew yet and I'm afraid of blowing up my blanks.
Rod
Rod
kovalcik
Member
begin rant/ The way carbide tools are marketed really is a disservice to the turning community. They have people sold that conventional tools are hard to use and sharpen and that carbide is good for everything. \end rant
The roughing gouge is probably the easiest tool to use and sharpen. It is very forgiving. They will get your blanks round and close to size in short order. IMO they are easier to use than the carbide tools. They are easy to sharpen with a simple jig (Woverine or Black hawk, or make you own), or even freehand. I would do a Youtube search. Once you see how to use it, it is a cinch. I recommend capn eddie. Check some of his earlier videos to see the techniques. I am sure there are others on there also. I con't do youtube from work, but I will try to find some tonight.
A skew takes a little practice and instruction (again search for capn eddie on youtube) but no other tool will give a better finish than a sharp skew and they are not that scary once you see the proper technique. While some go crazy getting a sharp edge on their skews, it is also very easy to quickly touch a skew up with a diamond stone and get a passable edge.
I am not saying to throw the carbide tools away, just don't limit your self or let yourself be intimidated that gouges and skew are hard to use.
The last thig I will say is don't be so conerned with "turning a lot quicker". Take small bites and learn how the tools cut (Carbide and steel). Once that becomes second nature, you will get a feel for when you can be more aggressive and when you need to tread lightly.
The roughing gouge is probably the easiest tool to use and sharpen. It is very forgiving. They will get your blanks round and close to size in short order. IMO they are easier to use than the carbide tools. They are easy to sharpen with a simple jig (Woverine or Black hawk, or make you own), or even freehand. I would do a Youtube search. Once you see how to use it, it is a cinch. I recommend capn eddie. Check some of his earlier videos to see the techniques. I am sure there are others on there also. I con't do youtube from work, but I will try to find some tonight.
A skew takes a little practice and instruction (again search for capn eddie on youtube) but no other tool will give a better finish than a sharp skew and they are not that scary once you see the proper technique. While some go crazy getting a sharp edge on their skews, it is also very easy to quickly touch a skew up with a diamond stone and get a passable edge.
I am not saying to throw the carbide tools away, just don't limit your self or let yourself be intimidated that gouges and skew are hard to use.
The last thig I will say is don't be so conerned with "turning a lot quicker". Take small bites and learn how the tools cut (Carbide and steel). Once that becomes second nature, you will get a feel for when you can be more aggressive and when you need to tread lightly.
ed4copies
Local Chapter Manager
Hey Rod!!
CAN I explain it, certainly!!!!!
And my wording is EXCELLENT, so you should all understand
. However, experience at attempting this has led me to the conclusion that a "moving picture" is worth a WHOLE LOT of words, so I created a series of videos. Some of them can be seen in the IAP library!! The BEST spot to see them all is here : Exotic Blanks :: How To Videos
I would direct your attention to the section labelled, "Alternate material Series". Although most of the turning is done with a skew, there is one vid where I used a gouge and a scraper, as well as a skew--just to show different ways to reach the same goal.
There is one observation I would like to make that MAY be unpopular: There is a COST to any EDUCATION!!! I learned in the mid-1990's, when the internet was NOT "user-friendly" and there were no "clubs" for pen turners who did "plastic"---in fact we were the "Darkside of pen turning, which was the red-haired stepchild of Woodturning" In short, very few CARED how to turn plastic (for jollies, you may want to look at old threads on IAP---some GREAT turners proclaiming they will NEVER turn plastic!!)
So what?? So, I blew up a LOT of blanks!!! I did NOT call CSUSA and request replacements-- no one offered a "guaranteed pen", they just sold me blanks and a one page "tutorial" telling me to go slow and use a scraper----two techniques that I will now tell you are the WRONG thing to do with plastics. But, it WAS conventional wisdom!!! Fortunately, I have never been encumbered by a pre-disposition to read instructions, so I "did it my way" and ultimately it worked.
Buy a few blanks---AA is a good place to start!! It is the most "turner-friendly" of the "plastics" (IMO). You WILL chip the ends off a few---THAT is the cost of education.
When the "Vendor-forums" open, I suggest you all add ExoticBlanks. I just had to erase a full paragraph, because current rules would not allow it in this forum.
It will be a great relief to get back to saying anything I want, without worrying about mentioning products made by other members of the IAP who are, incidentally suppliers of ExoticBlanks.com.
There will be MUCH more information available SOON!!! This information will be particularly valuable to those who want to master "plastics". And we will attempt to make the whole process light-reading.
I believe you come to the IAP for ENTERTAINMENT as well as EDUCATION, I will be going back to doing BOTH. Join us on "ExoticBlanks.com-corner of IAP"
Happy Monday!!!!
Ed
Ed
edstreet
Member
People, seriously? Is this going to come down to yet another carbide vs real chisels debate again?
There are many facts that is not known in this case and to help to OP out more information is needed and not for everyone to jump to conclusions and get finicky over the tooling when in fact it most likely is method of application.
There are many facts that is not known in this case and to help to OP out more information is needed and not for everyone to jump to conclusions and get finicky over the tooling when in fact it most likely is method of application.
alphageek
Former Moderator
Actually, I just re-read the thread - I don't see any serious debate. I do see lots of good tips about both.
PeetyInMich
Member
I personally use a woodchuck and approach a fresh "square" blank from an end and work the side of the insert against the blank with an aggressive cut to avoid an "interrupted cut". By that I mean that I want to with a few lateral swipes turn square into cylindrical with the side of the carbide so that I am not "hammering off" the corners and microfracturing the material, once it is cylindrical I can shape it as I please. It works for me.