Our larger "oven" is nothing...
Our larger "oven" is nothing more than the lower section of a storage rack, boarded up on all sides with foil-faced foam insulation board. The entire 4' x 3' x 8' space can be quickly heated to over 150F
Get Hot Summer Days Even In The Dead Of WinterEvery time I work on a project, I think to myself, "Is there a better way of doing this?" For my personality, getting comfortable with the status quo without progressing and improving drives me crazy. Some people can do the same thing for years without it ever crossing their mind that they could modify the process in some way to make it better. I'm sure there are writers out there that still create scripts or novels on their trusty old typewriter, forgoing modern conveniences like computers and word processing. I see many installers that have a similar mentality, sticking to "what they know," rather than trying new and improved techniques and products. I'm not saying that everything that is new is better, but keeping an open mind to new ideas is always a good idea. Over the next several issues I will be sharing some of my favorite fabrication tips and tricks, that while simple, can increase efficiency and improve the quality of a project.
The Shop Oven
Custom fabrication requires many different kinds of products, including adhesives, resins, body fillers and primers. The curing rate and times of all these things depend on temperature. I often read about installers who have a tough time fabricating during the winter because of cold and freezing temperatures. Although it's hard for me to relate to anything below 40 degrees Fahrenheit (living in sunny southern California), I came across a quick and cost-effective way to deal with cold climates. Build your own shop oven! I always seem to get a chuckle when I suggest this idea, but any installer who has used a heat gun to try to force some fiberglass or paint to cure on a cold winter night knows how much time can be wasted when the project is held up because something isn't curing properly. I use the term "oven" loosely because I'm not talking about the steel contraption we all have in our kitchens.
One of the best ways to maximize efficiency of custom fabrication during the winter months is to create a space large enough to fit a large enclosure or panel that can be heated between 90 and 150F to accelerate cure times. Some installers are happy using their heat guns, while others use heat lamps, but I have steered away from those methods because they aren't efficient and tend to heat unevenly. I know others use cardboard boxes with heaters and think it's "good enough." While the "hot box" is better than nothing, cardboard isn't much of an insulator and doesn't work well in extreme temperatures. Rather than making a box out of cardboard or MDF, I made an "oven" using readily available foam insulation board which can be found at your local home improvement warehouse. You can stroll down to the insulation section and purchase some 1" to 1 1/4" thick foam insulation board. Certain stores carry regular Styrofoam boards while others carry "foil-faced" urethane foam boards. Next, you'll want to check out the electric heater aisle and pick up a simple electric heating fan if you don't have one already. I've always preferred the heating fan because it doesn't direct heat in a concentrated area and doesn't get too hot. This is important because we're just trying to mimic a warm summer day, not bake cookies. Speaking of baking, you'll also want to stop by a grocery store and pick up a meat thermometer so that you can check the temperature inside your oven. Once you decide what size you want to make your oven, you can cut the foam to size on a table saw like butter. I would recommend making it as large as space and budget permit. For reference, I made the oven in our fabrication shop 4' tall, 3' wide and 8' deep. Whatever dimensions you choose, just make sure it will be able to house the largest project you intend to fabricate in addition to the heating fan inside the oven. The construction (if you can call it that) can be as simple as using duct tape to hold the foam boards together or as elaborate as lining the inside of a wooden or steel enclosure with the foam. Our larger oven was created by simply boarding up the lower section of a storage rack. For the bench top version we made for our retail shop, I glued 2 1/2" strips of 1/2" MDF together and made L-brackets that allowed me to screw the foam boards together at the joints. Two-inch fender washers keep the screws from pulling through the foam. Of course you will need one side of the oven that opens for access, which should be big enough to easily pass the parts through
It's important not to get too carried away with the oven because forcing certain things to cure too quickly will cause excessive warping. Remember to catalyze the resins and primers for the temperatures in the oven and not the outside temperature. Mixing a batch of "hot" resin, and then throwing the piece into the oven is only asking for trouble. Use the temperature control on the heater fan to achieve an appropriate temperature for your project, instead of always leaving the control on "max." Another use for the shop oven is to "heat cycle" pieces like custom dashes, by exposing them to high temperatures, similar to those inside a car during a hot summer day. "Heat cycling" will expose shrinkage problems before the project is finished.
Stay tuned for more shop "tricks and tips" in upcoming issues.
 Creating a simple shop "oven"...  Creating a simple shop "oven" out of insulation foam board will allow fiberglass resins, body fillers and primers to cure, even on a cold winter day. Simple MDF L-brackets hold the pieces of foam board together. |  Our trusty, old electric heating...  Our trusty, old electric heating fan gently and evenly warms up our oven without getting too hot. The temperature control allows the oven to reach temperatures between 100 and 160F, which mimics the inside of a car on a hot summer day. |  A meat thermometer, available...  A meat thermometer, available at most grocery stores, is a cheap and easy way to keep an eye on the temperature. |