Fabrication Supplies & Resources

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Fabrication is perhaps one of the most exciting, yet time consuming tasks in building large scale mobile audio/video systems. The excitement of generating an idea and following it through development into a finished installation is very rewarding professionally. This month we’re taking a look at many of the supplies and resources common to fabrication tasks, and some that are not so common. The focus is to point out inherent advantages that save time, save money, reduce exposure to chemicals, or dramatically increase the reliability of the finished product.

Body Filler (Filling Tasks)
Ease of sanding and minimal shrink are preferred attributes of a good fabrication body filler. Most installers refer to body filler as “Bondo”, when Bondo is actually a brand name. Other brands exist and, depending on where they are purchased, can do a better job for similar cost. Rage Gold by Evercoat is a great alternative to Bondo and sands much easier due to the inclusion of Hattonite, which reduces heat and friction created by aggressive sanding.

Catalyst/Mixers
Have you ever mixed the catalyst into polyester resin and smelled the mixture…sometimes for hours afterwards? How would you like to suppress that smell or even turn the smell into some other “flavor?” A chemical called “Styrene Suppressant” is a wax additive to the MEKP and Polyester Resin mixture which does just that by reducing styrene emissions. Styrene monomer is present in most GP resins used in the install bay. Styrene suppressants are mixed into the resin at about 1 percent by volume and drastically reduce the smell from the chemical reaction of the catalyst and resin or heavily mask the smell with a more pleasant scent, such as “bubble gum” and “citrus”. The suppressant is available from Composites One outlets nationwide as well as most commercial resin suppliers. One of the brand names is called STYRID and is produced by Specialty Products Company of New Jersey. The “bubble gum” scented suppressant is called Odor Mask and is produced by Dewolf.

Body Filler (Build-up Tasks)
Strength while doing build-up tasks as well as minimal shrinking of the material are notable attributes on which to focus. Due to the thickness of some tasks in “building layers,” build-up fillers that contain stranded or chopped fibers have more strength and may negate the need for additional layers of fiberglass mat or cloth. Mar-Glass by Marson and Everglass by Evercoat are a couple of favorites. If you have a hard time finding these, Bondo-Glass is easy to find at any auto parts or home improvement type of store. Kitty Hair by Evercoat is another install bay favorite.
Work Tip:
If you can help it, begin “shaping” body filler prior to it completely hardening to reduce sanding and shaping time. A shaping tool (also known as a “cheese grater”) is more effective than sandpaper if the body filler hasn’t fully cured. Mixed correctly, you should never need to walk away from body filler. Just keep shaping until it’s ready to sand.
When it comes to mixing the cream hardener into most body filler mixtures, almost every installer will tell you it’s a “feeling” thing when asked just how much hardener is right to mix with the body filler. One rule of thumb that is important to consider when you do “hot” mixes, is that longer dry times induce less material shrink.
Stay away from “Spot Putty” in tubes that have no hardener or catalyst mix because they depend on air dry time which may not allow the material to fully harden before moving on to sanding or application of a glue or primer.


High Build Sanding Primers
These primers are mixed (or catalyzed) to promote adhesion to the surface and allow multiple layers to form a surface for filling and finish sanding. Catalyzed build primers allow a fiberglass and MDF surface to blend and appear as one single surface. This takes care of the porous characteristic that is common with MDF when attempting to paint the surface, such as in fiberglass enclosures where the mounting baffle “rings” are constructed from MDF. Select Products offers the material as “Spray Bondo” and is available in gallon cans. Some of the other trade names are Poly Primer by PCL, Dura-Tec (702-003) by Dura Technologies, and Feather Fill or Slick Sand by Evercoat.
Work Tip:
One tip in storing catalyzed primer is to shake or flip the cans regularly. This keeps the filler material from separating out of the liquid. Every week or so, shake the material up (even if it’s not being used) to maximize the shelf life of the product. Always mix the material thoroughly before dispensing MEKP into the mixture and loading into a spray gun.
Bryan Schmitt, Senior Vehicle Designer at Rockford’s Tempe, Arizona RTTI facility had a few tips to add for some of the applications of the fabrication materials. “We always rough sand any body filler project with 80 grit and move right into a thinned out mixture of Dura-Tec catalyzed build primer,” he said. “We thin it down to build layers fast and speed up drying time on the project. Even with small runs, the time savings toward finish sanding is amazing.” Schmitt also recommends liberal use of SEM Guide Coat on any surface that will eventually be painted.

Resins
A good gallon of general-purpose polyester resin should go for about $20. If you can’t find that price in your Home Depot or auto parts store, buy from the local company supplying body shops. They sell so much resin at wholesale that it’s sold by the pound rather than by a packaging size (9.2 lbs to the gallon). Composites One is a national supplier of fabrication materials and may be a resource in your area.
If you have no local resource, Select Products offers a very aggressive price, but according to company president Robert Garza, “It’s the best value when the installer purchases the resin in quantities of 5 gallons (or more) at a time due to shipping and hazardous materials surcharges.”
Work Tip:
Always remember that polyester resins have a shelf life of 90-180 days before the viscosity begins to thicken.

Upholstery Adhesives
Absolutely the coolest stuff for wrapping complex surfaces with vinyl has to be the Heat Activated ADH6587 Adhesive available from Select Products. You can spray both the work piece and the vinyl and adhesion only begins after heating the material to at least 150 degrees with a heat gun. It allows complex shapes to be wrapped without the normal air dry “landau top” adhesive problems of sticking to itself when the vinyl edges flap over. Select suggests using it along with their HF Series (Heat Formable) vinyl. There’s also another version, ADH6302, for use on plastic surfaces rather than wood or fiberglass as the ADH6587 is intended for. In the extreme Arizona heat, this stuff is guaranteed not to peel up or release if applied properly!

Plastic Spray and Texture
SEM Products is one of the most recognized names in plastics and vinyl coatings. Whether it’s coloring, texturing, or both, SEM has about all any installer will ever need to produce professional looking interior surface finishes.
Many of their chemicals allow a plastic interior or exterior part to be professionally prepared and finished. The 3985 Texture Coating is especially useful to duplicate a variety of interior surface finishes. The 3835 Plastic Surface Prep and 3913 Surfacing Primer allow a variety of plastic surfaces to appear as the same material once colorized with a plastic paint. This is especially useful when a factory dash part or console has been modified to accept a headunit, controller, or video screen but needs to remain looking as if it were original equipment. Schmitt recommends that the 38203 Guide Coat be sprayed over the initial sanding primer coat of every body filler project, including fiberglass, ABS, and MDF surfaces, to identify any low or high spots. According to Schmitt, “Most installers tend to use a black epoxy spray paint that never fully saturates into the primer and will show through a second coat of (sealer) primer.” The 38203 Guide Coat leaves no surface traces and speeds up sanding tasks immensely. We use it on practically everything.” Nearly all automotive paint supply stores and most commercial upholstery suppliers offer the SEM products.
In addition to plastics refinishing chemicals, Select Products offers laminated ABS plastics that replicate many popular dash and trim patterns. Various woods as well as carbon fiber and aluminum finishes are available. All except the aluminum finish react well to heat forming if necessary. The laminated plastics can be a lifesaver when trying to do dash and console work in Mercedes, BMW, Lexus, etc.
Although there are literally hundreds of combinations of fabrication products and applications in which to use them, these common materials and tips should save any installer time and money in the long run while increasing the safety aspect of vapors and dangerous chemical inhalation. Keep up the fun and stay profitable!

Resources

Select Products
2400 S.W. 60th Way
Miramar, FL 33023
Tel (800) 458-6063
Fax (954) 985-2661
www.selectproducts.com


Marson
3700 Atlanta Ind. Pkwy. NW
Atlanta, GA 30331
Tel (404) 696-2730
Fax (800) 622-2855


3M Occupational Health and Respiratory Safety Division
3M Center, Bldg. 235-2W-70
St. Paul, MN 55514-1000
Tel (800) 243-4630


Evercoat Company
6600 Cornell Road
Cincinnati, OH 45242-2000
Tel (513) 489-7600
Fax (513) 489-9229


SEM Products Inc.
651 Michael Wylie Drive
Charlotte, NC 28217-1546
Tel (704) 522-1006
Fax (704) 522-7008


Dura Technologies
2720 South Willow Ave.
Bloomington, CA 92316
Tel (909) 877-8477


Composites One (30 locations Nationwide)
Corporate Office:
723 W. Algonquin Road
Arlington Heights, IL 60005
Tel (800) 621-8003
Specialty Products Company (STYRID) 115 Christopher Columbus Drive Jersey City, NJ 07302 Tel (201) 434-4700 Fax (201) 434-6052

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