Homemade Tubing Roller

With this homemade tubing roller you can beat the cost of custom shaped conduit.
By the MOTHER EARTH NEWS editors
September/October 1980
Add to My MSN

Man using the device to bend a length of tubing.

Content Tools

Related Content

Beautiful, Rustic Dog Fence

This rustic, resourcefully sustainable dog fence fits right into the landscape. Before you install a...

Step by step instructions for DIY projects

Detailed instructions for do-it-yourself projects

Living Off-Grid: How to Calculate the Size of Your Electrical System

A short simple explanation of how to project your electrical needs in order to size your electrical ...

Gaiam Restore Launches New Stress Relieving Products

Discover new products by Gaiam Restore, like the Hot/Cold Foot Roller.

If you've looked into building a backyard greenhouse, you know that one of the tools required to build the little "sun shed" is a tubing roller. Now such a device—if purchased—could cost you several hundreds of dollars, because it's normally a motor-driven "professionals only" machine.

A roller is used to shape lengths of standard conduit or electrical metallic tubing (EMT) into arcs (rather than merely to form a corner, as is the case with the far more common tube bender) for use in framing, toolmaking, and other kinds of fabrication. On several occasions MOTHER EARTH NEWS' shop crew has felt a sore need for one of the handy implements ... so finally they just up and built their own "North Carolina copy," which fills the bill perfectly!

Here's How It Works

Most store-bought tube-shapers run on electricity. Our version, though, uses a hand crank that not only feeds the conduit through swiftly and easily, but costs nothing to operate. The tool works like this: The bender itself is simply a pair of crosses—each made of two 18-inch long 2 X 4's—that "sandwich" a set of three grooved pulleys and a pair of support blocks. Two of the wheels (those that are in line along the same crosspiece) serve as idlers ... and the third pulley (positioned at one end of the other crosspiece) is the driver.

When the straight conduit is placed between the driver and the left idler, and the crank is turned, the tubing moves along until it contacts the right idler, which forces the pipe to bend slightly and to continue to bend till the entire section is arced. (This happens, of course, because the driver is positioned close enough to the idlers to force the conduit to bow.)

And It's Easy to Build!

The only tools you'll need in order to make this inexpensive device are a drill with an assortment of bits, a couple of wrenches, and a table saw with adjustable fence and blade height. Start by locating a good piece of 3/4" seasoned oak that's at least 5" wide and 30" in length. (While you're at it, find—or plan to cut from the first board, if it's large enough—another section measuring 3/4-inch  X 1 1/2-inch X 12 inches ... which will become the arm of the turning handle.)

Next, cut the plank in half and glue the two sections together so that—when it dries—you'll have a single piece of wood about 1 1/2 inches thick ... from which you'll cut three 5" X 5" pulley blanks. To do so, set your saw fence 5 inches from the blade and—beginning with a shallow cut and working progressively deeper—pass each blank through the saw, rotating the wood slightly at every pass, until the disks are perfectly round.

You can use the same method to form the grooves in the pulleys. Tilt the saw blade at a 45° angle, then set your fence 1 1/2 inches from its near side. Raise the blade 1 inch from the table (measured along the toothed disk's side), and pass the edge of the wheels through it. When the incision is complete around the entire circumference, turn the wooden circle over and cut the opposite side of the groove. (WARNING: During all of the foregoing sawing procedures, be extremely careful ... remember, your fingers will be very close to the area being cut!)

Trim the rest of the wooden components from a 76" length of 2 X 4, round the ends of the oak handle arm, and cut half-lap joints in the center of your crosses ... then assemble the roller. (NOTE: The critical measurements are [1] the 8-inch center-to-center distance between the two idler pulleys, and [2] the 4 1/2-inch span from the axis of the drive wheel to the midpoint of that 8-inch centerline.)

But That's Not All ...

This little gadget can't be beat for bending the support ribs on our "shoestring" greenhouse. What's more, if you take a tip from MOTHER EARTH NEW' Emerson Smyers, you can use the tool to perform any number of other tube-shaping chores: "Lengthen the channels in the lower section of each cross," Emerson says, "and slot the 1/4" mounting holes so the drive pulley can be moved closer to or farther from the others but can still be locked in place where desired. You can then produce just about any kind of arc ... even those required for large parabolic mirror frames!"

Previous | 1 | 2 | Next

Post a comment below.


2/9/2011 10:32:21 PM
It would be nice, even better, if a dim. drawing was added

Subscribe Today - Pay Now & Save 66% Off the Cover Price

First Name: *
Last Name: *
Address: *
City: *
State/Province: *
Zip/Postal Code:*
(* indicates a required item)
Canadian subs: 1 year, (includes postage & GST). Foreign subs: 1 year, . U.S. funds.
Canadian Subscribers - Click Here
Non US and Canadian Subscribers - Click Here

Lighten the Strain on the Earth and Your Budget

MOTHER EARTH NEWS is the guide to living — as one reader stated — “with little money and abundant happiness.” Every issue is an invaluable guide to leading a more sustainable life, covering ideas from fighting rising energy costs and protecting the environment to avoiding unnecessary spending on processed food. You’ll find tips for slashing heating bills; growing fresh, natural produce at home; and more. MOTHER EARTH NEWS helps you cut costs without sacrificing modern luxuries.

At MOTHER EARTH NEWS, we are dedicated to conserving our planet’s natural resources while helping you conserve your financial resources. That’s why we want you to save money and trees by subscribing through our earth-friendly automatic renewal savings plan. By paying with a credit card, you save an additional $5 and get 6 issues of MOTHER EARTH NEWS for only $12.00 (USA only).

You may also use the Bill Me option and pay $17.00 for 6 issues.