PSI collet- -

[Philip Duffy]

OK, I am a sucker for new toys and today my PSI collet kit arrived from Amazon. Anxious to give it a try I drilled the appropriate hole in a test piece, seated it properly, tightened it up as best I could and brought up the tail stock. I then proceeded to make some cuts, coves and beads. Nearing the end of the exercise I let the shallow roughing gouge drift towards the headstock. BAAAMMM!! The collet exploded and pieces of the chuck section went flying into the walls. Fortunately I was not hurt by these "bullets" and the only real loss is the o-ring that holds the 4 sections together.

[Philip Duffy]

#1 Today, 4:21 PM
Philip Duffy
Member Join Date: Feb 2003
Location: W'burg, VA
Posts: 308

PSI collet- -

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OK, I am a sucker for new toys and today my PSI collet kit arrived from Amazon. Anxious to give it a try I drilled the appropriate hole in a test piece, seated it properly, tightened it up as best I could and brought up the tail stock. I then proceeded to make some cuts, coves and beads. Nearing the end of the exercise I let the shallow roughing gouge drift towards the headstock. BAAAMMM!! The collet exploded and pieces of the chuck section went flying into the walls. Fortunately I was not hurt by these "bullets" and the only real loss is the o-ring that holds the 4 sections together. So back to the Instructions I go, looking for some cautionary tales, warning or Something. NOTHING! They expect a whole lot of intuitive knowlege these days, guys and gals, so do not let the toys kill you!! p

[Thomas Canfield]

Philip,

I take it that this is the expanding collet chuck that works in a 1 3/8" recess. I have probably turned about 40 or so small bowls and saucers up to 3" D x up to 2" D and usually only have about 1/16" deep recess made using a Bedan tool. A Forstner bit leaves the center point and usually a cut line at the outer edge and I stopped using the drill for that reason. I have had the recess break out or split on a few (maybe 3 or so) occasions but never had the chuck come apart.

All that said, I was helping a friend at a workday recently and he did "pull" the bowl off the chuck and there was the 4 flying pieces of chuck. The "o" ring was still there.

The expanding collet chuck is a neat tool and the little bowls that you can make from "scrap" make nice gifts. This should be a warning to stand out of the line of fire, use sharp tools, and take light cuts since there may be a limited grip. I do like the PSI with sharp serrations all the way better than the Woodcraft that has a wide groove at the outside or bottom of recess.

[John Keeton]

I haven't used one of these, but I recall looking at it and thinking - what if that sucker turned loose???? Nothing holding the innards!

Is it possible you contacted the chuck with the gouge? Or, that the recess gave way?

[Philip Duffy]

Hi John, Pretty sure the recess gave way. When I drilled the hole I made sure there was plenty of wood outboard of the hole and that the hole was deep enough. I do not think that there was any significant contract from my tool to the wood that would have caused such an explosion. The speed was far less than max recommended and since the tailstock was in contact the piece was turning as smooth as glass.
All this is just another reminder that one can not be too careful, you must wear your safety gear and take precautions because accidents do happen! Phil

[Bernie Weishapl]

Glad you weren't hurt Phil. Great reminder to wear safety gear. Thanks.

[Thomas Canfield]

Phillip,

You said that the tailstock was in use. I don't see how the piece could have come out with that much surface contact unless there was a dramatic catch or you were turning a long piece. I usually use the PSI collet only for small pieces up to 4" D with 3" a safer bet and 2" thickness or less, and cross grain. I use a screw chuck to turn the outside, make the 1 3/8" recess using a Bedan tool (again, several have been 1/32" after sanding bottom and before mounting chuck), and then mount on the chuck. In turning the inside, I use push cuts so that the force is directed into the headstock. The failure I mention in earlier post was when someone was using a pull cut which puts tension force against the recess and make it more likely to break the grains. I encourage you to keep trying it starting with 1/8" recess or more and use a bedan or scraper to have the flat bottom. A Forstner bit will have a weaker recess than one cut with the Bedan. http://www.sawmillcreek.org/showthread.php?t=152409 This shows my granddaughter with bowl that has about 3/32" recess and I felt comfortable with her wearing safety glasses only and my "assisting " the work.