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View Full Version : Chatter, chatter.



Dale Thompson
09-22-2006, 10:54 AM
Hi Folks,
I haven't turned a pen in at least a couple of years. I tried a few the other day and am getting a bit of "chatter". Since I am perfect :) :) , I can only blame my tools! :rolleyes: ;)

My mandrel shows a maximum of .007" TIR over a distance of about 10". Any thoughts as to whether or not this could be the problem. I don't remember using the mandrel as a crowbar lately but who knows what I may do in one of my senior moments? :eek: Thanks.

Dale T.

Bernie Weishapl
09-22-2006, 11:07 AM
Hey Dale how have you been? Isn't it the piths when you can't get good tools anymore and I know about the senior moments. I was told it is called Old Timers.:eek: :p :p

I get some chatter on mine Dale if I crank the tailstock to tight on the mandrel. I found if I back it off just a skoosh it quits.

Jim Becker
09-22-2006, 11:12 AM
Bernie has a good point...be very careful about how tight the tailstock is engaging the mandrel. You can at a minimum deflect it, causing minor vibration that is correctable by backing off. But in the worse case, you can actually bend the mandrel, making it undesirable to even use...that costs money! Use the tailstock to support it lightly, but with minimal pressure. A live center with a blunter point that fits into the rounded recess of the mandrel end is also a good idea.

Frank Kobilsek
09-22-2006, 11:23 AM
Dale, My trick to set the pressure tailstock to pen mandrel. Bring tailstock into the cone of the mandrel but not contactly the bottom. With lathe a a slow to medium speed advance the tailstock while your finger is resting gently on the revolving center. Your finger is holding the revolving center stopped. When the revolving center begins to spin stop advancing the tailstock and lock stuff down.

I wreck my first mandrel and the cone of my revolving center before I figured things out.
Frank

Ken Fitzgerald
09-22-2006, 11:29 AM
Good to see you posting again Dale! Somebody has to keep Spring in line!

Frank Fusco
09-22-2006, 12:44 PM
On a penturning forum (can I say that here? ;) ) a fellow wrote that his new skew chattered constantly.
I advised him to return it and exchange for a male skew. He had gotten a female skew and, as we all know, those female chatter contantly. :rolleyes:

Corey Hallagan
09-22-2006, 6:42 PM
Hi Dale, good to hear from you. Like Bernie said if you back off the pressure then it should work ok. I have one PSI mandrell ( I am told that they don't harden the steel like Berea and CS USA) that I have tightened to much and it chatters all the time due to being a bit out of round.

Corey

Karl Laustrup
09-22-2006, 8:04 PM
Pesh, I don't have a clue what's causing the chatter while you are doing pens. :confused:

I'm just glad that your "chattering" on the Creek again. :D :D

Karl

Joe Melton
09-22-2006, 11:14 PM
You really can't expect an 8 dollar fixture (the mandrel) to be that precise, can you? I can't recall ever having a mandrel that was close to perfectly true. Of course, the mt arbor has to be right, too, as well as the hole screwed into the arbor. Don't forget that the dimple in the end of the mandrel must be concentric with the od of the mandrel. Did I mention that the (probably) cheap live center has to turn true, too? Is your spindle perfectly aligned with the live center? Doesn't matter when you are turning bowls, but with pens it does.
I always turn down to close to the bushings, turn the lathe off, loosen the nut and rotate the blanks 180 degrees, tighten the nut and turn again. I do the same thing with every sanding grit. That takes out enough of this problem so that people cannot see or feel it on the finished pen.
Hope this makes sense!
Joe

Tyler Howell
09-23-2006, 12:11 AM
Chatter Chatter is right!!
Must be Pesh back in the creek. It's been so quiet around here till now:rolleyes: :D :D
Good to see you floating buddy. Now do a little back stroke;)