Creative Woodworks & crafts 1998-07, страница 25

THE FINER POINTS OF CUTTING ALABASTER:

-Selecting patterns and designs. Choose larger, less iniricaLe designs. The trivet and cross projects are much easier lo saw than the coyote or "Monumental Trail's End." Note: Patterns are located in Full Size Pattern Section No. 2. I found that, unlike wood, alabaster is not flexible. Saw kerfs will not flex open when you turn the workpiece around to switch the direction of ihe blade. Instead, the blade gets lodged/pinched during the turn because the width (or depth) of the blade is much greater than the thickness of Ihe blade. (The blade thickness produces the size of the kerf). As the blade lodges in the alabaster, il causes the workpiece to be lifted and then slammed back down on the tablelop, often breaking the project. Try to choose designs that maintain a minimum of 1/4" of material between saw cuts. Areas with 1/8" or less are very likely lo break off, such as the spear handle on "Monumental Trail's End." I also recommend eliminating definition lines. They do not show up very well and they also weaken the project.

-Drilling holes for interior cutout areas. Use a 1/16"-Dia. drill bit or smaller, and bore at a moderate to slow speed. Use a backer board under the material while drilling. Maintain firm pressure on top of the material to reduce break-out on the bottom. Position the hole as close as possible to the center of the area to be cut out. While drilling, il helps to reduce the downward pressure slightly as the bit nears the bottom of the workpiece. Proceed slowly to complete the hole as the bit exils the bottom.

-Blade selection. I found the No. 4 and No. 5 skip tooth blades worked best, at moderate to slow cutting speed. The alabaster eats up blades pretty fast, so don't be too surprised. For example, on the trivet, a blade lasts about long enough to make one culout opening. I experimented with both oil and water to cool the blade and hopefully prolong the cutting capacity. However, both fluids only slowed down the sawing action. As a matter of fact, cutting action ceased entirely until the fluid dissipated!

-Dealing with the dust. The processes of cutting, shaping, and sanding alabaster produce fine, powdery,

When selecting patterns, choose larger, less intricate designs.

Alabaster can be surfaced just like wood. My Performax drum sander worked great for this purpose.

chalk-like dust. A dust collector will gather up much of it but I'd recommend wearing a dust mask as well. You may want to have a brush handy while sawing to clear away excess dusi that accumulates on top of the work-piece and tablelop. It's apparently a little heavier than wood dust, because the scroll saw blower does not remove it as easily. The dust will coat everything, so be prepared. This coating will also dry out your hands and, in turn, make them really slippery, so be careful not to drop your projects! Note: while sawing, be sure to maintain constant hand pressure on top of the alabaster to prevent it from being lifted up and slammed back down on the scroll saw table top. Whenever this occurs, your project is very likely to break!

-Sanding and shaping. 1 was amazed to discover that I could run the alabaster through my Performax drum sander. It works great to surface the material and equally as well to reduce the thickness. I also found that a belt sander works great on it, as does hand sanding, filing, etc. Needle Files, rasps, knives, and anything else you regularly use to touch up your wood projects work equally as well on alabaster, including all those attachments for your rotary tools and reciprocating tools. Note: be aware that this materia) does cause your tools to loose their cutting edges much faster than wood.

-Finishing. I found that natural Watco Danish oil works great on the alabaster. It darkens it slightly and seems to accentuate the dark to light color variations, producing a marble-like appearance. After ihe Finish dries, give the alabaster a coat of aulomobile wax, and you'll be happily surprised with the beautiful sheen you'll achieve with a little buffing and polishing.

So get some alabaster, follow these tips, and try your hand at the cross and trivet! For Ihe future, I'm envisioning a stunning alabaster chess set, a pair of elegant alabaster candleholders, and lots of other exciting new challenges for my scroll saw! Enjoy!

Aiabasfer is available from Crystal Valley Stone and Alabaster, 1308 County Road 129 No. 14. Glenwood Springs, CO 81601, (970) 947 0006.

Scrolling alabaster is dusty work, so make sure you're prepared for it.

Alabaster can also be finished with conventional woodworking tools. Shown here is an alabaster disc being smoothed with a belt sander.