JPM Hot Rods

Things to Consider

At JPM Hot Rods we are committed to providing the longest lasting fiberglass reproductions, to do this we have adopted many of Gibbon Fiberglass’s ideas for building the best quality body.

Designing to allow for inevitable expansion and contraction
The first thing we do differently from other manufacturers is to assemble the body in separate pieces, just like the original metal body and unlike a “silhouette” one-piece body shell. This gives us a more “metal” look with the proper lines and seams and eliminates stress cracking that commonly occurs in the corners of the trunk opening. It also adds many vibration escape joints so the glass absorbs a smaller portion of the vibrations.

Secondly, we look at the expansion-contraction effect which shows up mainly in 90 degree corners and where reinforcement is bonded to the part. We have addressed a portion of the 90 degree corner problem through the separate piece construction.

Consistent panel fit and alignment
In order to save the customer as much work as we can, we build our bodies on frames built from reproduction rails, not mock jigs. We have chosen the reproductions rails for the fact that most cars are built on them these days, we do have original ford frames available to build some of our body styles on, or we will build the body on your frame at no charge, saving you hours of shimming for body-to-frame fit. For the ultimate package in panel fit and alignment we offer the UNI-Body option. We assemble each door in the body to insure a proper door fit. All bodies come with a steel cowl brace installed and doors hinged and latched. Rumble or trunk lids are hung, hinged, adjusted. We do the necessary body work on the mold flashing lines at the plant so you receive a body that is ready to be cured, sanded and then painted.

Choosing the best raw materials
We use only the best resin and glass fiber materials available to ensure your glass body will be as strong and durable as possible.

Common Misconceptions and Questions
This may be your first fiberglass street rod project so we would like to clarify some common misconceptions associated with fiberglass in general.

Weight
Fiberglass is not always lighter than steel. To achieve the same strength, fiberglass should be about 3/16” thick. This makes it even heavier than metal in some circumstances. In the racing industry, where weight is a factor, parts can be made lighter (thinner). But that makes them fragile and easily damaged and even sag across long horizontal areas.

Chopper Gun or Hand Laid
This is probably the most misunderstood procedure in the fiberglass process. Most fiberglass companies utilize the “hand laid fiberglass” feature as a selling point. This is quite deceiving. When fiberglass resin and fiber material are applied in a mold, every square centimeter of that material needs to be hand rolled. A special roller is used to compress the material into the mold eliminating all air bubbles and ensuring complete saturation of the fiber material. This process is the same regardless of how the lamination is applied. Applying the material to the mold with a chopper gun allows for more uniform material thickness and allows the resin to be applied more evenly throughout the mold. When a piece is said to be “hand-laid”, a pre-made piece of fiberglass mat is saturated with resin using a bucket and a brush and laid in the mold. The finished product from this procedure will show the patchwork of all the pieces $14,000. This is expensive enough to be out of reach for most smaller manufacturers. Have you ever heard of a major boat manufacturer boast that their product is hand-laid? We utilize both lamination procedures in our facility and have two complete chopper-gun machines.

Glossy gel coat finish
Our product’s finished surface is not always glossy and polished like our competition. There is a reason for this that is very important. We use a sandable primer gel-coat that is very easy for you to work with and has terrific sanding and painting qualities. This product is more expensive than the normal glossy finish gel-coat, but does not have much shine. The glossy finish gel-coat is shinny and very polishable, but does not have good sanding or primer qualities. Some manufacturers also increase the luster of components by polishing the molds, but this damages the shape and edges of the molds. This is a very important feature for us to clarify. To maintain a high gloss finish inside a mold, it has to be polished repeatedly, and maintained that way. After just a few times sanding and buffing a mold, the crisp edges of the body lines and reveals start to round of and lose their sharpness. This is very noticeable even on finished street rods.

Wood or Steel Reinforcement
This is mostly a matter of opinion. Both work if installed correctly. We primarily utilize wood for several reasons. First of all, Henry Ford reinforced all of his steel bodies with wood when these cars were new. If you are not very familiar with the original bodies of this era, take a look inside of one that is unfinished. You’ll see we use a lot of the same wood reinforcement as the original, including the package tray, tack strips, and top bows. The best reason to use wood is that wood absorbs resin making is possible to bond wood to fiberglass in a very permanent fashion. Wood also makes it easier to fasten the upholstery in place. We also install a steel dash brace in every body to securely mount the steering column. Some of our open bodies receive additional steel reinforcement to strengthen the door post/floor area. Several manufacturers utilize a full steel tubing structure inside their bodies. This system makes the car quite heavy and is not strong enough to be a safety feature. The small square tubing that is added, is not going to protect you in a collision. For this reason, we have added our new roll bar options on our upgrade page. We build each of these bodies to order and we will be happy to add a special brace or structure for your specific needs.