Bowl from one board question

[Quinn McCarthy]

I started making my first bowl from 1 board. There is 10 rings and the rings are 3/4" high. The rings are 1/2" wide. I have the rings made and the first and second ring glued to the mdf glue up chuck. I was able to make rings on the top of the base ring to center the second ring but I am alittle perplexed on what the best way is to make sure the next rings are centered. The only way I can think of is just lining them up my feel but if you alignment isn't true you might end up with a shorter bowl. I was thinking about maybe getting half of the rings on and then getting it roughed in so I didn't have to be trying to turn at the bottom of the base. I designed it to be straight along the inside and outside. The top ring is about 12 1/4"

Thanks for the help.

Quinn

[Robert McGowen]

Hi Quinn,

There really isn't any reason you can't turn it as you go. I would turn just to the edge of the transition so that you leave yourself a little wiggle room to finish the piece. Once the inside and outside are turned down some, it should be easy to center the next ring. The problem with glueing it all at once and turning it, is that each error on each ring is multiplied to the very last ring. You could either end up with a VERY thin bowl or even turn away the top rings completely. You could also glue two rings together and then add that section to the bowl, so that you are turning two rings at a time. That will cut your glue time in half. Good luck!

[Gary Conklin]

http://www.fwcwt.org/images/bowl_fro...d_tutorial.htm

[Malcolm Tibbetts]

Quinn, Robert as given you good advice.

Here's one more tip. Take a disc of MDF, drill a centered hole, screw it onto a screw chuck, score concentric circles, use the contentric circles to temporarily position and attach the next ring (or pair of rings) with just a couple dabs of hot melt glue. Now, use your tailstock cone in the center of the MDF hole to position the attached ring(s) against the lower ring in your bowl. This will center each step of the construction and help avoid the center of the stack from drifting away from center. Have fun.

[Quinn McCarthy]

Thanks for all of the help. I thought about gluing pairs of rings together but I have no way of making a flat ring. I have the bottoms of each ring sanded flat. and have been making then parralell on the lathe.

I will let you know how it goes.

Thanks again.

Quinn

[Richard Madison]

A slight variation on what they said- a 5/8 or 3/4 particle board disc on a dedicated faceplate, with the scored, concentric circles. Each ring has one fairly flat side (maybe with a little sanding) that can be fairly well centered and attached to the disc with double stick tape. Am just not a fan of hot melt, but guess it works fine too. Turn and sand side two flat. Remove from spindle, install tailstock adapter (about $20) and install on tailstock. Put workpiece on spindle, apply glue, judiciously apply pressure with tailstock, making sure the alignment is correct before the glue joint "locks up". Let glue set. Release tailstock clamp, rotate spindle while pulling back on tailstock to unscrew the adapter. Back tailstock away and pry particle board disc loose from work piece. Lotta words, but simple procedure. Hope you could follow that.

With a thin pad this same disc also serves as a friction chuck, and the faceplate of a doughnut chuck.

[Malcolm Tibbetts]

Richard, with regard to the hot melt, I probably should explain (at least to some folks), that I do not use the hot melt on the flat surfaces of the rings - it is not applied between the ring and the MDF (or particle board). I clamp the ring in place first with a couple of spring clamps and only apply a few short beads at the intersection between the ring edge and the disc - sort of like a fillet style of weld. Putting the hot melt between the two flat surfaces would make it very difficult to keep the ring oriented flat and it would make it difficult to remove later.

[Richard Madison]

Thanks Malcolm. I assumed that, but probably not everyone would. And the hot glue method does have the advantage of being able to center the ring very carefully before applying glue. With double-stick tape it is necessary to set the ring in the right place on the first attempt, as there is no adjusting it once stuck.