After reading a recent article on making potato chips, I thought some of MOTHER EARTH NEWS' readers might be interested in a gadget I designed for cutting spuds into spiral slices. As anyone who's made potato chips knows, the secret of success is getting the meat of the vegetable evenly thin, so that it'll fry quickly (before it absorbs too much oil) but still hold together.
My hand-cranked gizmo is, admittedly, a bit complicated, but it's fun to use and works wonderfully. To make your own spiral chipper, you'll need a block of hardwood (I used birch) measuring 3/4-by-1-1/4-by-15-3/4 inches, a 3/4-inch birch dowel that's 10-1/2 inches in length, a 5/16-inch I.D. by 3/8-inch O.D. by 2-1/4-inch compression spring, a 12-1/4-inch-long piece of 5/16-18 threaded rod, a 1/4-by-2-7/16-inch hardwood dowel, a 7/16-by-2-5/8-inch scrap of (preferably) stainless steel that's 1/32 inch thick, a 1/8-by-1-inch steel dowel pin, a piece of flat metal measuring 1/8-by-1/2-by-3 inches, a 2-inch-long wooden crank handle, a 1/4-by-2-1/2-inch coarse-threaded machine bolt with a nut and flat washer, a 5/16-18 hex nut, a No. 6 by 1/2-inch roundhead wood screw and some assorted brads.
First, cut your block into three sections: one 11-1/4 inches, the second 3 inches and the third 1-1/2 inches long. Then trim a 1-1/2-inch piece from the threaded rod and divide the 3/4-inch dowel into three equal parts.
Next, drill three 3/4-inch holes through the 11-1/4-inch block (which will be the contraption's base) at the points shown in the illustration of this article's image gallery, and bore a 1/4-inch opening halfway between the two 3/4-inch cavities that are closest together. Finish up the base by center-boring a 7/16-inch hole, 3/8 inch deep, directly over the just-drilled quarter-incher.
Then take your 3-inch-long block and bore holes at each end-centered and 2-1/4 inches apart using the 3/4-inch bit. With that done, chisel a 5/16-inch-square channel longitudinally down the center of the same piece of wood, drill a 15/64-inch hole through the billet at the midpoint of this groove and remove 3/8-inch from each end of the chunk, cutting right across the holes and reducing its overall length to 2-1/4 inches.
Trim the third piece of hardwood to 3/4-by-3/4-by-1-1/2 inches, then cross-drill two 1/2-inch openings through the block, each centered and at a point 1-1/4 inches from one end. Then center-bore a 1/4-inch hole about 3/4 inches deep into the flat end of the pierced rectangle, thread it with a 5/16-18 tap, and lop off the cross-bored tip 1/4 inch from the end to create four wooden "fingers."
With that task complete, carve a crescent-shaped depression — 3/8 inch deep and approximately 2-1/8 inches in length — in one of the 3/4-inch dowels, making its midpoint about 1-3/8 inches from one end of the post. Then drill two 7/64-inch holes, parallel to the concave face of the indentation, at points 3/8 inch and 2-1/4 inches from the dowel's short end. You can also take this opportunity to bore a 21/64-inch hole 3/8 inch from one end of each of the remaining two posts.
Now, grind the 1-1/2-inch section of threaded rod flat on one side and file the opposite side, just at its ends, enough to form 1/4-inch-square platforms at the tips, which you can then pierce with 5/64-inch holes prior to mounting the piece — threaded side up — in your previously channeled block, using small brass brads. Once this step is completed, glue the 1/4-inch dowel into the hole in the smooth side of the block, lock it in place with another brad and sand the opposite end of the thin peg lightly so that it can slide in and out of the small opening in the base without binding.
The cutter's stainless steel blade can be fabricated by trimming a centered 5/32-by-1/2-inch slot in one end and drilling a 5/32-inch hole — also centered — 3/8 inch from its opposite (lower) end. Hold the strip at the bottom and twist its righthand edge toward you about 5 degrees. Then sharpen the back side of that edge above the bend, screw the blade to the carved post with the bevel facing the wood and drive your 1/8-inch steel pin into the dowel, through the slot above the mounting screw.
Next, glue all three posts in position (making sure the top holes and pin are in line) and secure them from the side with brads. Once that's done, all that's left is to work up the handle and crank mechanism, which is simply a matter of threading the flat bar (1/4-20 at one end and 5/16-18 at the other), rounding its sharp edges, center-boring the wooden crank handle so it will accept the 1/4-inch bolt and locking the parts together with the hex nuts.
Finally, assemble the whole gadget by slipping the spring over the 1/4-inch dowel, placing the entire half-nut/carrier unit between the two closest pegs and into the hole in the base, and — while pushing down on the sprung component — sliding the long threaded rod through the guideposts and twisting it into the "fingered" block. At this point, you can, for the sake of cleaning convenience, coat all the tool's wooden parts with polyurethane.
To use the slicer, merely clamp it to the corner of a table and — pushing down on the spring-loaded carrier — pull the screw assembly out far enough to accommodate the length of your to-be-cut potato. Next, push the spud onto the steel pin, slide the fingered block against its opposite end, and start cranking. The threaded rod will feed the tuber at just the right rate to create spirals of perfectly even thickness, thus beating the "by guess and by golly" hand-slicing method all hollow.
You will probably find, as I did, that cranking out spuds and deep-frying them — skin and all — will turn out tasty family treats and you won't be disappointed at what your gadget can do (perhaps with the help of a stronger spring) with carrots and turnips come salad-making time!