| Bending wood is not the daunting task that it appears | | | | wood is commonly soaked asabove, but it is bent over |
| to be at first glance. Depending on the degree of bend, | | | | a hot bending jig, either electric, or heated with a |
| and whether or not the bend is compound, there are a | | | | propane torch. |
| couple of methods for bending wood. | | | | Brittle woods are supported on the outside of the bend |
| First, you need to have a form to bend your wood | | | | with a thin stainless steel band to help prevent |
| around and clamp to hold thedesired shape. Most bent | | | | cracking. |
| wood will have a certain degree of "springback", so | | | | Green woods can be bent much in the same way, or |
| you must build your form with an allowance for this. | | | | by heating the wood over hotcoals or with a good |
| And, unfortunately, there is no established formula for | | | | heat gun. |
| determining the degree of springback that a given | | | | For projects where lamination is objectionable, or when |
| species of wood will produce. Springback is also | | | | the wood is to be bent incompound curves, a steam |
| influenced by the bending method used. That is to say | | | | box is the answer. One can be made fairly |
| that steamed wood will spring, or "unbend" more than | | | | economically from |
| wood that is laminated and glued. | | | | PVC pipe, but it needs to be supported to keep the |
| Another variable is the type of glue used in laminating. | | | | pipe from deforming. The ends of the pipe need to be |
| As a general rule, the tighter the bend, the more the | | | | closed with a screw cap on at least one end, to allow |
| wood will spring back, making the allowance a matter | | | | access to the interior. Fit the other end of the pipe with |
| of trial and error at best. | | | | a DWV reducing tee, and attach a radiator hose to |
| As laminating thin strips is the easiest method, we'll | | | | the side outlet and to a new gas can to hold sufficient |
| begin with that process. Thefinished thickness of the | | | | water to last through the job. The water may be |
| project will have a direct bearing on the size of the | | | | heated with a hot plate or a propane burner. |
| strips to be used, but generally, the heaviest strip to | | | | Drill through the pipe slightly below center in two or |
| use is about one quarter of an inch thick. Tight bends | | | | three locations and insert dowelsfor the wood to rest |
| may have to be done with one eighth inch strips or | | | | on. Steam must be allowed to circulate freely around |
| thinner, depending on the wood species. Sounds like a | | | | the wood for even penetration. A hole about one half |
| lot of experimenting, but I'm afraid that's a necessary | | | | inch in diameter should be drilled in the cap furthest |
| evil. | | | | from the steam inlet to allow circulation. When you |
| The form required for laminating can be as simple as a | | | | build the support frame for the steam box, pitch the |
| piece of pipe or as complex asa multi-station die. I like | | | | box toward the steam inlet to allow the condensation |
| to keep things as simple as possible. | | | | to return to the water supply |
| When laminating thin strips, you can minimize effort and | | | | Rule of thumb says that wood should be steamed |
| spring back by soaking thestrips before bending, and | | | | fifteen minutes per inch of thickness,but here again, |
| clamping them in the mold without gluing. Once they | | | | some experimenting will be necessary. The wood |
| are dry,remove them from the mold, spread the glue | | | | needs to be placed into the form as quickly as |
| and re-clamp them in the mold. Line the mold with | | | | possible, because as the wood cools, it is more difficult |
| waxed paper to prevent the lamination from sticking to | | | | to bend. Make sure that your wood is at least two |
| the mold. | | | | feet longer than the finished part, because it's nearly |
| When I soak strips, I do so in an open container, and | | | | impossible to bend a 3/4" piece of wood that is less |
| depending on the wood and thesize of the strips, I | | | | than a foot long, so that last foot will have to be cut |
| soak them from 15 minutes to overnight. I also mix in a | | | | off after the wood is dry. Clamp the wood in the form |
| half cup of fabric softener per gallon of water. I find | | | | securely, and leave it there until it is completely cool. If |
| that it softens wood nearly as well as fabric. | | | | you are working with multiple pieces, place them in the |
| If the project is small, and open time on the glue is not | | | | steam box at approximately the interval required to |
| a factor, I'll use poly-vinylacetate, or aliphatic resin glue. | | | | place the piece in the form and clamp it, and remove |
| If I need more working time, I'll use epoxy or resorcinol. I | | | | them from the box in the same order. |
| stay away from the quick setting epoxies, however, | | | | With a little practice and a little luck, it shouldn't take |
| because they rarely harden to the extent that the | | | | long to become proficient in woodbending. Good luck |
| slow sets do. If you're using light colored wood, | | | | with your project, and if I can be of any help or |
| resorcinol dries to a reddish color which might be | | | | answer any questions, feel free to respond to this |
| objectionable on a finished project. | | | | post, or email me at . |
| When bending thin woods such as guitar sides, the | | | | |