Est. 1998 — 27 years of woodworking knowledge
Pen turning question
Terry Spawn in St.Paul
>I know I have read the answer to this somewhere, but know I cannot find it. When turning on a standard mandrel with the normal bushings, what does it mean when the barrels come out something less than perfectly round? ie. the cross section is slightly oval. Is the mandrel bent from too much/not enough pressure?
Re: Pen turning question
YoYoSpin
>Terry,
Yes, a bent mandrel might be the cause. Also, have a look at how tight that end-nut is on the mandrel...too tight might cause the steel rod to buckle a little, causing some out-of-round effects. If that doesn't fix it, check the ID of the bushings to insure that there's not too much slop with the OD of the mandrel's rod...sometimes one manufacturer's bushings are not compatible with another manufacturer's mandrel. Finally, try a mandrel that has an adjustable length feature. Sometimes, if the mandrel's steel rod is too long, and shimmed up with a lot of bushings, you may get some whipping, where the rod gets a little deformed through the centrifugal forces.
Best regards,
Ed D.
Your son' pen looks OK
Dave Smith
>Hi Terry,
I just checked the pen your son gave me and it looks pretty good. Maybe he can give you some advise. BWG
Check to see if there is any glue on the in side of the barrel. Also, burrs on the tube end can cause the pen blank to be off center when turning. Using a sanding disk to square the ends can cause burrs on one side of the tube end. On small pens it doesn't take much to get wood out of round. The glue or burrs are usually removed when pressing the pen together so the metal part is centered and the out of round wood is not. DAMHIKT
Dave Smith
I turn them round, sometimes, in Longview, WA.
Re: Pen turning question
Larry G.
>Something else to check:
Make sure that the morse taper on the lathe is clean. A small amount of dirt will cause a straight mandrel to wobble.
Larry
Hand Turned Pens at http://pws.chartermi.net/~lgottlieb2/
Re: Pen turning question *LINK*
RevDoug
>Also, the morse taper on the mandrel.
Turn 'em round,
RevDoug
Wood Spun Round
Re: Your son' pen looks OK
Terry Spawn in St.Paul
>Good to hear from you. Thanks for the advice, I'll talk to my son. Actually we are both having the problem. It is intermittent, and I think you may have hit it with the glue idea. It started when we switched to the foaming polyurethane glue. While we are using a pen trimmer, I looked and sure enough there is a little glue that has foamed into the tubes. I thought after using the trimmer that it would be removed enough, but it is there, and I bet it is not there after the pieces are pressed together. Thanks your help.