8 Springs are removed from the old canvas casing, cleaned, and checked for cracks. Each row of springs is different and some may be different in size and gauge. It is important to keep the springs in the original order they came in.
9 Measurements are taken from the old burlap casing and recorded onto the legend card. Height, width, and overall length of the burlap are needed to reproduce the new casing. Variations in the spacing of the pockets should also be noted.
10 Spring tension is an important part of the rebuild. To create the correct spring tension, some pockets may be shorter than others. This measurement is also added to the legend card so that it can be sewn into the new casing.
11 New spring casings are cut from burlap and marked according to the measurements taken from the original casing and recorded on the legend card. Individual pockets are then sewn into the new casings that divide and space each spring for proper alignment and tensioning.
12 Each spring is compressed and inserted into its pocket and then it is sewn closed. After the row of springs has been sewn in, the springs are turned and expanded vertically in their pocket. The rows of springs are now ready to be reinstalled into the edge wire frame.
13 Each casing of springs is hog ringed together one row at a time by following the legend card. Working in a methodical way ensures that no hog rings are skipped. Tension rods are secured in place and the edge wire frame is hog ringed to the outside edges of the spring unit.
Seatback Supports
Now is a good time to address the mounting arm on the backrest of the front seat. The arm is a structural element to the seatback, and on a four-door car it is attached to the seat bottom with bolts and does not pivot. The backrest upholstery covers these supports, hiding them from view.
The design is different on a two-door car. The seat is designed to allow the backrest to be tilted forward for access to the rear seat. Because of this pivot action, the support arms are somewhat visible. The factory painted the metal arms to help them blend in with the upholstery, but their color choices were very generic.
The support arms need to be cleaned and any chips in the old paint should be sanded smooth before priming the metal. A complementary color can then be sprayed on the support arms and allowed to dry.
Zigzag Springs
The bottom seat frame of this project uses modern zigzag springs. The name obviously comes from the design of the spring. Clean the springs by wire brushing them to remove any rust and debris.
The backrest support arms are visible and they deserve to be cleaned up to look like new. Cleaning, sanding, and a good color coat make them fit in with the new seat cover that is installed over the freshly tensioned spring set.
Check for broken or loose springs and repair them as necessary. If the springs are rusty from mouse damage they need to be washed with a 50/50 solution of bleach and water before they are painted. Painting the springs seals them to keep them from smelling bad. The paint also helps prevent further corrosion. I use Rust-Oleum to paint the springs in my projects. What makes it a great paint is that it covers well and comes in rattle cans that are ready to use.
I don’t recommend powder coating the seat springs. The powder coating does not like to be flexed as this cracks the coating, causing it to chip off.
The adjustable seat tracks must be serviced along with the lower seat springs. Clean the seat tracks and lubricate the roller bearings so that the track can move freely. It is not recommended to sand blast the seat tracks. Grit gets into the roller bearings and causes the seat tracks to grind and wear the bearings.
This seat bottom frame is fitted with zigzag springs. These springs provide all the support necessary for a comfortable ride and yet they are easy to work on. The attached adjustable seat tracks give the seat the correct ride height and secure the frame to the floor of the car.
Decorative trim panels are used to hide unsightly components in the car. The small apron panels are stripped of their old cover material and the surface is cleaned and straightened in preparation for a new layer of upholstery.
Adding a felt underliner material before the new vinyl cover is applied softens the surface of the metal. The new cover material is held in place by a coat of contact cement that has been sprayed onto the back surface of the material.
Trim Panels and Seat Skirts
Along the outsides of the seat are additional upholstered panels that conceal the raw edges and working elements of the seat. These decorative pieces need to be stripped and reconditioned before they can be reinstalled. Most of the panels are covered or wrapped with the same upholstery material as the interior. Some trim panels are metal or molded plastic and are painted to match the interior color scheme.
The simple flat apron panels are stripped down and the surface is cleaned. The metal is straightened and a felt underliner is applied to the face of the panel and trimmed to the edge. The underliner gives the panel a softer appearance when it is re-covered.
New vinyl is cut about 1 inch oversize of the panel to allow for the material to wrap around the backside of the panel. Glue is sprayed onto the backside edges of the panel and the overhanging vinyl material.
After the glue gets tacky the edges of the vinyl should be pulled taut as it is wrapped around the panel.
A little heat from a heat gun helps the vinyl conform to the panel when pulled around the corners. Press the vinyl into the glue to secure it to the panel. Trim off the excess vinyl that has bunched up on the backside of the panel.
Although seat skirts are mostly decorative, they do have a function: The seat skirt conceals the seat track and pivot point of the seatback. Some skirt panels have decorative chrome or stainless trim attached. This must be removed before the panel can be re-covered. First remove the inner liner of the skirt by lifting the staples holding it in place. The stainless trim is fastened to the skirt panel by small screws or tabs that are bent over to hold the trim in place. Remove any screws that may be holding the trim to the panel and from the backside of the panel carefully lift the tabs or pins that hold the trim in place. Try not to break off any of the fasteners or damage the trim when removing it from the panel.
Wrapping the trim panels in vinyl gives the piece a nice, soft appearance.