What am I doing wrong?

[sequoia]

This is a bottle stopper question, but I thought this might apply to a lot more than just bottle stoppers.

When I am turning a bottle stopper (kits like the BS1 at Penn State) with their chuck mounted, I can't help lately, but feel that the turning wood is out of balance or it appears to me.

The material seems harder to work with and the gouge skips off the wood as it is turning. I have to be even more careful when this happens as I don't want to have a big chunk get caught and ruin the piece. I must be doing something wrong. I feel sometimes this happens when I turn pens where there is a slight out of round look down near the nib. It's ever so slightly.

I hope this is technique and can be corrected easily. I really would appreciate your thoughts and suggestions.

Thank you all.

Matt

 

[KenV]

How are you sharpening your edges???? Sounds like dull tools and not using the bevel.

 

[plantman]

Matt; Could be an alignment problem on the lathe itself. Mount a drive center in your head stock and a live center in your tail stock. Bring the two together and clamp down the tail stock and see if the points meet. Slowly rotate your head stock by hand to see if they stay on centers. If they are not centered you may have to shim one or the other to correct. As you turn larger objects, any amount of variation will be greatly increased. If this checks out, take Ken's advice and sharpen your tools. Use the bevel to approach your work and check the height and distance of your tool post and bar. Practice make perfect, or at least makes it seem better !! Jim S

 

[SDB777]

Another thing to consider....you are using a wood lathe, not a precision metal lathe. The accuracy of a wood lathe is going to be good...not perfect.



Scott (I overthink stuff too) B

 

[sequoia]

Thank you Ken and Jim,

Regarding the alignment. I mounted the drive center and also the live center. Please see image below. When I rotate the drive center, it barely comes out of center to the live center, but is very so slightly noticeable. Do you think this could be causing it?

Direct link to photo: http://tinypic.com/r/2uswtj6/9

Regarding sharpness. I have to admit, I was most likely using a less than sharp gouge. But I don't just use one gouge when I turn, it's a few. I will start with sharpening, but am curious what you all have to think about the lathe alignment.

I can measure runout, but I'm curious at what point on the lathe can I measure that would be the most accurate.

Thanks again!

Matt

 

[sequoia]

Jim,

When you say use the bevel, can you please explain that in a little more detail?

Much appreciated - Matt

 

[Mortalis]

Theoretically, even if your center is running out you would eventually turn the piece to whatever center of rotation the holder is running around.

Sounds to me if you are having this issue on other items you are trying to turn that you may have a sharpening issue with your tool(s). As a rule of my thumb, I sharpen/touchup my turning tool(s) before I use them for the first time that day and then when I start to have an issue with the tool requiring more pressure than I feel is normal I will take it back to the grinder. AOne thing I always do before staring to sharpen is to mark the tip with a marker so I know when the marker is gone, the tip is ground. You might be surprised how little dulling it takes to make a tool cut badly.