Simple task, difficult? - Long Cylinders

[alex grams]

I am looking at making a cylinder for a pedestal table that needs to be 6" x 24". While turning a small, short cylinder is easy, on such a larger, longer cylinder, I think maintaining a good cylindricity and consistant radius will be a challenge. Even a small variance on such a large piece would be noticable when you feel the piece. Are there any good tricks or methods for making a smooth, even cut over such a long surface?

Thanks in advance.

[tom martin]

Alex, The method I use is to take a caliper and a parting tool and cut a series of groves to the desired diameter. Then take down the cylinder to the depth of those groves. I don't turn a lot of cylinders, so there may be a better way to do it, but this method works.
Tom

[Mel Fulks]

I used to work for an especially good turner who used to occasionally get orders for some type of machine rollers. He used to sometimes use a block plane with the lathe on. Most furniture turnings benefit from either entasis,or a straight taper.

[Jerry Marcantel]

When I got my first lathe in '83, I had to make a table base for a customer. I didn't like the idea of only having a 12" tool rest, so went to a welding shop and had one made that was just a little longer that between spur and live center when extended to max distance. The long tool rest was nothing more that a 2 x 2 with 1/4" walls, and 2 legs that were 2" shorter than my swing. I then got a piece of 1/8" x 2" angle iron, and bolted it to the square tubed tool rest. To get equal distance from center to the tool rest, I measured from the spur and live center point, and clamped the tool rest to the lathe base. I then used a small C clamp on my gouge to only allow so much inward travel. That's the way I made "perfect" rods, cylinders or barrels. It's a simple set up, but a duplicator is probably less hassel.......Jerry (in Tucson)

[Richard Coers]

I use Tom's method. At the start of sanding, I make up a 11" long block sander with 100 or 120 grit glued to a wood block. It will either take out the high points, or tell you where to turn more. When doing long tapers like walking canes, I use the mini Porter-Cable belt sander held at a 45 degree angle to the work. Lathe is on really slow speeds of course.

[Michael Stafford]

I use the procedure that Tom Martin describes but after I turn off the waste between the parting tool cuts I take a straight edge and place it against the cylinder and mark any high spots with a pencil. It will take several tries to get it to a perfect cylinder. Jerry Marcantel's method will also work but I like to make one final pass with a large skew to eliminate as much sanding as possible.

You can also make a temporary long tool rest using some black iron pipe and a "Tee" fitting if you can find pipe that will fit in your tool slide. It will work in a pinch. Not recommended for heavy work but will work for clean up cuts on a cylinder.

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[Prashun Patel]

Getting it to rough dimension is relatively straight forward with a good tool rest and calipers.

To get it perfect (in the absence of perfect tool control) I like to use a flat nosed scraper and 80 grit sandpaper. Sanding roughs the surface, such that a scraper (or even a skew) will burnish and highlight the high/low spots.

In the end, the sandpaper will make it 'perfect enough'.

Don't worry, it's actually easier and more forgiving than it seems.

[Don Orr]

Please don't take this the wrong way but if this is going to be a pedestal under a table, how many people are going to feel it to check for perfectness? Is this a case of close enough is good enough? And as Mel said, consider a taper or entasis which can make things look more pleasing to the eye. They have been used for millenia for a reason. Don't forget to show us pictures of your finished product.

[alex grams]

Don, I won't take that the wrong way, but 99% of the people on the creek, like me, are probably their own biggest critics. I doubt anyone else would ever notice, but I would, hah.

I don't think a taper would work, as I am going to mount legs on the column, akin to this table: