How to?

[James P Lile]

Hi, I'm a newbie.

I was wondering how people cut out shapes in a bowl. There seems to be a lot of designs, such as trees cut into the sides of bowls, and I was wondering what is the most efficient way to make these shapes.

Thanks.

Here is a couple of examples of what I would like to learn how to do.

http://www.aawforum.org/photopost/showphoto.php?photo=11670&ppuser=30579

http://www.aawforum.org/photopost/showphoto.php?photo=11663&ppuser=7117

 

[john lucas]

That is a technique we call piercing. It's usually done with a High speed grinder. And I'm talking really high speed. 400,000RPM. These are Dental tools or modifications of Dental grinders. They are expensive usually running $300 or more.
I have done it with a Dremel that runs at 36,000 rpm but it is very slow and painfully hard to control. The slower speed tends to want to follow the grain of the wood so you fight it constantly. The Dental grinders are almost like writing with a pen.
The other downside of piercing is it needs to be done on wood that is very thin. Less than 1/8" is ideal. When I took a class from Binh Pho I turned a goblet. I had made the base of the goblet a tapered thickness. It was really obvious when it got thicker than 1/8" . The cuts were very slow. It's even worse with a slow speed grinder like the Dremel.

 

[James P Lile]

Thanks,

Where would find one the dental grinders?


I wonder if I called all the dentist in town if they would sell some of their old tools...

 

[Bill Boehme]

There have been a few dealers selling either reconditioned dental tools or similar tools to woodturners, but every time I get interested in a particular one, thee is so much negative feedback from owners of the tool that it scares me away from it.I am sure that thee are some good dealers somewhere, but I just have not come across one of them yet.For a whiole there was a local guy who refurbished used dental tools, but he is no longer doing it. You could ask your dentist, but I think that many of them have maintenance contracts with companies that periodically refurbish their tools or trade then in for new ones when they can no longer be refurbished. The ones used by your dentist are much more expensive than the ones that are sold for wood piercing. I suspect that dentists do not just throw away their old drills.

 

[Bill Boehme]

I did some searching and saw new prices in the $2000 range (probably for a complete system). I did find this place where hand piece prices were in the $200 to $300 range. This brings back some fuzzy memories from a Binh Pho demo at SWAT. He talked about two-hole and four-hole hand pieces, but I do not recall which are better. For wood piercing, you do not want water cooling the burr, but cooling air is probably a good idea. There are also special connectors that go on the back of the hand piece to hook up the air and water lines). You will need a good assortment of burrs and they get dull or break all too often. I believe that Binh has some information on his web site. The air turbines need frequent maintenance so do not forget about that expense. Let us know if you find something useful. I would love to do some piercing, but it involves a fairly large expenditure to get all the needed stuff.

 

[John Torchick]

Dentists?

Just a thought-contact local dentists who might be upgrading their equipment?

 

[Bill Blasic]

You can go on Ebay and you can find whole systems at very very good prices. The thing is that dental drills (400,000 rpm) are angled. The NSK Presto system which has a straight head cost over twice what the dental systems cost. One other thing is the dental systems require a drop of oil where the NSK does not.
Bill

 

[James P Lile]

Thanks for all the information. Its going to be a little while before I can spend the coin needed for the good stuff. I might try a drimmel soon, just to see how it (does/doesn't) work.


Once I get something done, I post a photo or 2.

 

[john lucas]

Here is one.
http://www.nskamericacorp.com/prod_handtools_presto.aspx
Do a google search for Ultra High speed air grinders and you'll find more. Binh Pho sells them I believe but I could not find his website. Here's a video you might find interesting.
http://www.youtube.com/watch?v=LiEVA3kOyg0

Here's another one
http://www.razertip.com/turbine.htm

 

[Patrick Miller]

turbocarver

You might check out the Turbocarver also. Not as expensive as the NSK and the one we use (bought used) works well and has been quite reliable. Use a good air line filter just ahead of these units and lube per the instructions (if required) and they will last a long time.

 

[Lee Tourtelotte]

FYI--Brian McEvoy is a very accomplished, professional turner living in Canada.
He does a lot of piercing in his work and sells on his website several different high quality, dental type piercing tools in the $500. range. A turning friend of mine recently bought one of these systems from Brian and has said that he is completely satisfied with the performance it gave him..

These piercing systems are described on his web site.

Go to: http://www.onegoodturn.ca

Happy Trails,

Lee Tourtelotte
Minneapolis, MN
(Baja Canada)

 

[Richard Coers]

Just a thought-contact local dentists who might be upgrading their equipment?

That's about like buying a used medical grade vacuum pump. Both could be a poster child for bio hazard. Lots of blood and bacteria in the human mouth, ugh! I'd make sure I knew the dentist, and he would have to swear that thing had been in the autoclave before I bought it.

 

[Jeff Gilfor]

The Master Carver brand from woodcarver's supply(http://www.woodcarverssupply.com/) is nice and cost effective. They stand behind the equipment, and are very easy to deal with.