Lady in distress...need some helpful advice please.

[Wayne Hribar]

Ok, my husband is 100% to blame. He has addicted me to turning pens. Yes, this is a good thing, but I wanted to try something other than wood. I got a great deal on some Corian and I thought "Alright, something different, pretty, and nifty." Ahhhhhhh, not really. I cannot for the life of me get a hole through one without splitting it out, melting it, cracking it...etc....

I am using a bullet point bit for 7mm pens tubes right now. I have tried faster drilling, slower drilling, pausing while drilling, ice water, soap, glycerin, different homemade jigs, different bits, and plenty of crossing my fingers...I just can't seem to get it.

What am I doing wrong???? Is this impossible???? Any advice, suggestions, help, or thoughts are greatly appreciated.

Thanks in advance,
Mrs. Wayne

[Ron Smith ... Richmond, VA]

Ahhhhhhh, not really. I cannot for the life of me get a hole through one without splitting it out, melting it, cracking it...etc....
What am I doing wrong???? Is this impossible???? Any advice, suggestions, help, or thoughts are greatly appreciated.

Thanks in advance,
Mrs. Wayne

you're trying. The thing you have to remember about Corian is that is actually high tech plastic. It will most certainly melt and clog up the flutes of your drill bit. Sounds like you've been trying everything. All I can suggest with the limited aspect I have is A) make certain you are dead center when you start to drill (using a blank vise is a good thing), B) go slowly and back the drill out often to clean out shavings and C) make sure you cut your blanks a little long to allow the tearout when the bit comes through the bottom. You can then cut off the excess to the right length. Different colors act differently when drilled. Some are a lot more brittle than others due to the concentration of stone chips used. The more solid colors have more resin in them, making them easier to drill, in my experience. Keep trying. I had problems at first, and after quite a few, I rarely have a problem. Hope I've helped a little. Good luck.

Ron

[Dale Thompson]

Mrs. Wayne,
I've never turned Corian but I have done quite a bit of work with those "other" plastic-type materials. Heat is almost ALWAYS the problem. I talked my doctor into a prescription for hypodermic needles. He actually BOUGHT my line about getting glue into 1/4" dovetails, oiling slot car bearings and drilling stuff like plastic. I've had very good luck with drilling at a slow speed (to prevent melting and bit buildup), withdrawing the bit frequently to clear chips and "injecting" water to completely fill the hole before resuming drilling. If the bit is hot to the touch, wait till it cools. Patience, especially toward the end of the hole when heat buildup is greatest, is essential. After the halfway point, or even before, your passes should probably not exceed 3/8 - 1/2".

If I can do it, any other Type A person should be able to do it also. Admittedly, I DO shake a lot toward the bottom. :) Good Luck!!

Dale T.

[Dennis Peacock]

Greetings Mrs. Wayne....!!! :)

Corian is usually only 1/2" thick and drilling EXACTLY in the center for the entire length of the blank is something that needs to be done with a drill press, a machinist vice and good sharp drill bits.

Now....since I have far less than the optimum setup for this....and yes I am now making pens out of corian.....I decided to laminate to pieces together to make a 1" thick blank. I use medium CA glue, rub the pices together (after roughing up the surfaces to be mated of course), quickly line up the pieces, apply spring clamps and let dry for 24 hours.

I then drill with the drill bit splitting the glue line and fairly close to the center of the blank. Constant feed rate and backing out once in a while to clear the chips is a good thing. Works really good for me. I'm not careful enough to drill a 1/4" hole in a 1/2" blank and it be STRAIGHT.! :)

Corian makes a realy nice pen.....but you better be ready to sharpen those turning tools often...even with HSS turning tools.

Hope this helps some.....

[Michael Cody]

OK, my husband is 100% to blame. He has addicted me to turning pens. Yes, this is a good thing, but I wanted to try something other than wood. I got a great deal on some Corian and I thought "Alright, something different, pretty, and nifty." Ahhhhhhh, not really. I cannot for the life of me get a hole through one without splitting it out, melting it, cracking it...etc....

I am using a bullet point bit for 7mm pens tubes right now. I have tried faster drilling, slower drilling, pausing while drilling, ice water, soap, glycerin, different homemade jigs, different bits, and plenty of crossing my fingers...I just can't seem to get it.

What am I doing wrong???? Is this impossible???? Any advice, suggestions, help, or thoughts are greatly appreciated.

Thanks in advance,
Mrs. Wayne

3 things screw you up with plastic -- heat, bit wander, speed....


I drill a lot of plastic, here is how I do it...


1. cut the blank about 1/4"-3/8" long .... will tell you why later...

2. The 2 halves of the pen are only about 2 1/4" or so.. so you don't have that far to go.... if you are drilling with the lathe (IE a jacobs chuck holding the drill bit, something else holding the Corian -- drill 1/4" and back out the drill & clean any debris from the flutes. Then spritz it with water. Same thing for a Drill Press but you are moving the drill instead of the tail stock... Repeat until you are 1/4" from end of the blank.. <b>"DON'T DRILL THROUGH IT!!!!"</b> I mark my drill bits w/a bit masking tape or set my drill press to the right depth .. This way you don't have bit wander, you are killing the heat and your speed should be fairly fast .. say 1000-1100 rpm. This will keep bit wander down and if you only drill 1/4" at a time you keep the heat down.. Also since you didn't drill all the way through -- you don't have blowout!!

3. Once you've got it drilled, glue in the tubes.

4. When the tubes are dry use your mitre saw <b> and some kind of holding jig</b>, hand saw, even the lathe to cut the last 1/4" off exposing the tube...

Viola -- you have a drilled blank. If you batch them you really don't have much more time into them than a normal blank and they are ready to fly.

[John Miliunas]

Lots of neat ideas, thus far, though I think I like Mike C's the best. At the same time, I'm a bit lazy and here's what I've done to minimize blowout on mine. As mentioned, cut them a bit long. Drill speed long about 1000 rpm works OK. Clear chips often. The one additional thing I've done (and I'm not even positive it's worth it, but seems to work for me...) is to put wrap one or two thicknesses of plain, old masking tape at the bottom. I use one of those commercially available centering vises and the tape usually ends up just below the jaws. Seems to work for me and, when I do get a bit of blowout, it's typically below what I need for the tube. YMMV, but it's worked for me. :cool:

[harry strasil]

for what its worth, keep a container of baby powder at hand and dip the bit in it, the powder is talc and makes the bit slick so the stuff drilled will slide easily on it, find a speed that the chips curl out and do not bind in the material, pull the bit out often to clean and redip in the powder, this is how I drill stuff that has a tendency to ball up and create heat.


Irnsrgn

[Dave Richards]

I've never done pens let alone Corian ones, though I might if I ever finish the cradle and get my shop arranged so there's room for a small lathe. Still, I have a thought or maybe a question about a procedure for dealing with the holes.

Are you folks who are dealing with this stuff buying it in blanks already cut for pens or working with larger pieces and cutting them down? If the latter, could you set up a small core box bit in the router table and cut grooves along the edges of a couple of pieces and glue them together?

I'm thinking that if you start with fairly long pieces and cut the grooves, you could then cut these long pieces into the short lengths needed for pens.

I know this doesn't directly give you the options for diagonal seams between different colors and that sort of thing although I can see a way to make that stuff work, too.

For the fat pens, the groove could be cut on the face of the Corian at an appropriate distance from the edge. If the pen will be no more that the thickness of the Corian, the groove could be cut down the edge itself.

Maybe I'm all wet on this. If so, please forgive my error.

[Wayne Hribar]

Wow, all the ideas and advice are great! I was up until 1 am trying to figure this out. The trash guy is really going to hate me while he's lugging away pounds and pounds of ruined corian! :)

I will be working away again today to try and make this work for me. My hubby just smiles and continues merrily along with his wood....wait until I get one of mine done!! :)

I turned my first bowl quite awhile ago, and I really beat my hands up during the sanding process. I gave up on the turning hobby, but am so glad I tried pens. There is almost instant gratification in turning one, and I love the idea of trying different materials for different looks.

If I have any success, I will post and let everyone know. Don't stop with the ideas or suggestions though, if you could see the huge pile of ruined blanks that I have you would know that I need every one of them!!

Thanks again to all,
Mrs. Wayne

[Ken Salisbury]

OK - Let me jump in here.

The main key to drilling Corian or acrylic acetate blanks is the heat buildup causes the bit/hole to be clogged. You must withdraw the bit and clear any buildup. I do that with a toothbrush which I have hanging on a string from my drill press. I withdraw the bit 6 or 7 times in drilling an individual blank and simply hit the bit with the toothbrush.

Cutting the blanks a little longer and not drilling all the way through is a good idea. I set the stop on my drill press to accomplish that. Some times I do that, but not always. After drilling I cut the blanks to exact length (before inserting tubes).

As far as getting the holes straight it is a matter of having a way to insure the blank is held perpendicular to the drill bit. I use a simple "V" block in my drill press vice clamped to the DP table (the one in the picture below has been used on more that 1000 blanks). Note the file mark on the front jaw of the vise which I use to align the next blank to be drilled. Start the hole slowly to eliminate drill bit wandering. After you get about an 1/8" deep you can feed a little faster. Of course - withdrawing the bit multiple times to clear the flutes. I also use parabolic drill bits which help in removing the debris.
The picture of the blanks below were some I drilled a week or so ago using the method described above. As you can see the hole are straight through ½" square Corian. Occassional you will still have a failure. In the batch shown below I believe I had 2 or 3 failures.

It actually is very easy to do - just be patient.