Fabricating Large Wooden Columns

Brainstorming session about how to make 9-foot-high non-loadbearing decorative columns. February 5, 2007

Question
I would like to make some decorative (non-load bearing) pillars/columns for a client. The total height of the pillars will be 3m(+/-9ft). Painted white, so I don't have to worry about what grade of wood to use.

I am aware of the fact that one cannot put that length of lumber in a lathe. The only idea I have is to laminate the timber to a PVC pipe, fill the gaps with resin, sand and paint. Does this sound feasible, or are there better alternatives?

Forum Responses
(Architectural Woodworking Forum)
From contributor J:
I would stave build it, then turn it on a lathe. Barring that, I would find a company that builds columns and buy one. There are many companies which have experience in that area. Laminating around PVC is not a good idea - something is going to fail due to seasonal movement of the wood.



From contributor R:
Contact George Pagels Co. Their whole business is making columns. They made some walnut columns for me that were great and I thought reasonably priced.


From contributor D:
The problem with columns of PVC - other than its exclusion of everybody's favorite building material - is that they have no entasis. A column without entasis is just a tube.

The classic columns all have the same fairly complicated formula to figure the taper to make them look right. A proper column not only looks right, but looks a whole heck of a lot better than some tube. You can easily approximate the taper on the lathe, without actually having to taper the staves. Study good photographs and you will see how the entasis lays out.



From the original questioner:
Thanks for the info. I was planning on wrapping the finished shape in a couple of sheets of fiberglass, specifically to avoid seasonal movement. How/where does one find a lathe that can chuck something that long?

The columns wouldn't be load bearing and entasis could be worked in, should I get the shaping right. My biggest concern would be the lathe.



From contributor J:
Seasonal movement of wood cannot be avoided - something is going to break, eventually. If fiberglass is to be the final surface, then skip the wood and find a material that is compatible with the thermal shrinkage rates of PVC and fiberglass and use that as the bulk material.

As for a lathe large enough to turn columns, I built my own. They, like the columns, can be purchased, too. It all depends upon which business you wish to be in and where you wish to spend your money.

If you have no lathe, are only going to build a few columns, are not concerned with the design issues of classical columns, perhaps buying the columns would be the shortest path to completion of this task.



From contributor S:
There were lathes made to turn stuff that size at one time. In the UK, Wadkin used to build a monster called the RU. I know one guy who has one of these with an 18 foot bed. He's an architectural woodturner. Unfortunately he's over here in the UK. But realistically these lathes were always pretty rare and are getting rarer by the year.

So instead of PVC pipe, have you thought about using cardboard tube? This is made in a variety of standard sizes for manufacturing dry goods and food drums, etc. and the firms who make this seem to have fairly low minimum order quantities. These tubes are strong enough to stand up to shipping and being made from wood pulp, which is what paper is, will glue up using conventional wood glues without any worries about seasonal movement pulling the glue joints apart.



From the original questioner:
I could outsource the pillars, but that wouldn't be fun and I won't be able to put "column maker" on my business card.

I actually did give a thought to cardboard. Also thin MDF and ply. The nice thing about PVC is its availability, and if I do it right, its re-usability... I know we in South Africa use the cardboard forms for concrete pillars and such, but I still need to find a supplier. I thank you for your input.



From contributor D:
I currently turn up to 14 feet in length on a Powermatic with a wooden extension bed, all bolted to floor and wall. Recess the centers, turn it down slow, remote start and let it spin a while before stepping up to one exciting turning job! I learned to turn with a wood bed lathe, babbit bearings, open pulleys, that did up to 18 feet in length x 28" swing.

I missed the part about attaching wood to the PVC. Redundant in my opinion. Wood is the way it has been done (if not stone) for centuries, so it is achievable for you.



From contributor A:
Since it gets painted, why can't you turn it in sections? I don't know what kind of lathe experience you have, but if sufficient, you should be able to do it very easily. I would divide the column into thirds or divide it in half depending on your lathe, and put mortise and tenon on the ends so they nest together.