MGB Convertible Top Buyers Guide When looking to purchase a convertible top for your MGB there are a couple of key points of information you need to make a proper and informed decision.
1. What top frame do I have?
We will address the first part of this question, well first. The first thing to understand is that there are three different designs of folding bows, where the top folds down into the area behind the seats and one set of removable bows, where the top and bows are removed and stored in the trunk, or boot for British speakers. For British speakers, the top is also called “a hood”, which can get really confusing.
We call the first two folding bow designs “Grey Scissor Bows, because they are painted grey and the support arms fold towards the center of the car, like scissors.These bows were installed up to 1971, when they were replaced by the superior Black Folding Frame design.
Interchangeability of Tops
The four frames mentioned above are interchangeable and can be installed on any year of MGB, and it is very important to identify what you have, because your new top must be correct for your frame design. This is also a good time to upgrade your car to a different frame and top if you wish.
A popular alternative to the 1962-'70 Grey scissor folding frame is the two piece Grey stow-away frame. Changing to the Stow-Away frame is straight forward. The front bow assembly is unbolted from the original folding frame and reused. We recommend that chrome tonneau sockets (472-330 x 2) and pozi-drive screws (323-001 x 6) be used to make the installation look original. Because the Stow-Away design is a popular retrofit, we do offer tops with non-original zip out rear windows that make summertime driving more comfortable.
2. What was the original top material and what materials are available today? The standard material for British tops was what we call Everflex. It is a pretty thin material that folds and bends easily. As far as today's materials are concerned Everflex is certainly inferior, however if you must have that "as it left the showroom look" then go with the Everlfex.
Robbins Crush Grain Vinyl – The best American vinyl tops we’ve seen, period. By using Haartz Supreme 36-oz. pinpoint-grain vinyl (backed with pre-shrunk cotton cloth), you get a superior product. For greater durability and to ensure the seams remain water tight, seams are stitched, then electronically sealed. The 40-gauge rear window is made from Regalite B.U.V. Ultralight plastic, which offers superior resistance to UV rays and scratches. We offer tops in non-original American vinyl as an alternative to the more expensive British Everflex. Although the grain pattern is similar to Everflex, it is not going to pass as original. Feedback from customers generally indicates the American vinyl tops are a little stiffer than the Everflex. Aside from the originality aspect, these are superior tops in every way, and offer outstanding value for the money.
Robbins Imported English Everflex Vinyl –If you want your top to be as close to original as you can get, this is the only material to consider. Made in England and imported by Robbins, this material is accepted as original for all MGBs.
Robbins Stayfast Canvas –Absolutely the finest cloth top available. If originality is not your primary concern, Robbins Stayfast offers an opportunity to upgrade your top. Stayfast fabric uses 100% acrylic Glen Raven surface cloth, laminated to a pre-shrunk cotton backing cloth. Stayfast is engineered for high tensile and tear strength, but the fabric stays soft, supple and color-fast. The 40-gauge rear window is made from Regalite B.U.V. Ultralight plastic for superior resistance to UV rays and scratches. Because it is a woven fabric, it looks like the top on a Rolls-Royce Corniche more than a top on a British Sports car, and the biggest problem when the top is up is that people just naturally want to touch it. Stayfast has a practical side as well. Stayfast canvas resists fading and shrinking better than vinyl and does not stiffen up at lower temperatures. This means you don't have to be Hercules to put your top up on a cool morning.
3. Can you describe how the seams are put together? If a company is going to cut corners and save time and money this is the area in which they are going to do it, and many do. Many companies glue seams and put in one row (if you are lucky two rows) of stitching, and when first installed everything looks OK. As time marches on and the glue goes through the cold and hot cycles associated with daily temperatures, it starts to breakdown and puts all the stress on the seams. Without the additional holding of the glue the stitched seams will start to come apart. On the other hand Robbins spent their time, energy and resources figuring out a better way to hold seams together rather then searching out a better glue. The answer was heatsealing the seams. Heatsealing is essentially welding the material together which is stronger than any glue will be. On top of the heatsealing Robbins then reinforces the seams with double stitching to give the "joints" extra support.
4. What is included with a new top? All the necessary fasteners are included in our kits but they are not installed as there may be variations in the locations of existing mounting hardware.
5. Why Robbins Auto Tops? Over the years, Moss has offered tops from a variety of manufacturers. We settled on Robbins for several reasons, the primary consideration being quality. Robbins has a reputation among British car owners and restorers that is second to none. Robbins is committed to manufacturing high quality products which offer long term value to convertible owners.
Quality Material & Custom Workmanship: Robbins uses only first quality top material and original style components. Combine that with the finest custom workmanship, and you end up with well made long lasting tops that fit correctly and look sharp.
Computerized Cutting: Robbins has invested heavily in modern computer aided production equipment By using a Gerber® Cutting System and its CNC controls, materials can be processed without tooling by loading digitized patterns for cutting vinyl and canvas top material. This produces pieces that are 100% accurate every time. This means that the assembly of the tops proceeds smoothly, and the finished product is consistent and the installed fit is correct.
Factory Designs Duplicated or Improved: Robbins duplicates factory designs, and improves upon them when necessary. They add reinforcements where experience has shown them to be necessary. Advances in materials and technology have resulted in better heatsealing processes, which improves the quality and durability of the tops they make. Tops made with American Crush grain vinyl incorporate numerous modern features while the emphasis is on originality with the British Everflex tops.
Heatsealed Reinforcements: Robbins heatseals reinforcements in most of our products for extra strength and to prevent side to side shrinkage in tops. Heatsealed reinforcements will not bubble or fail over time as do most glued reinforcements. It takes more time and costs more, and you will never notice it looking at the top, but it means the useful life of the top is extended.
Plastic Windows: Robbins uses only full width Regalite B.U.V. and Ultrashield plastic sheets, to manufacture their plastic window assemblies.
Finish and Detail: Robbins purchases full width cloth and vinyl binding materials that are run to our specifications, to make most bindings we use to finish our tops and other products. Our bindings are more supple and sew on easily without bunching around tight curves on tops. Stitching in our products is held to a uniform length, and we do not ship products with broken or erratic stitches.
Testing and Quality Systems: Robbins performs stretch testing, sew testing and heatseal testing on samples of every batch of material they receive. Thread and plastic sheets used to make the rear windows are also tested before any of the material is passed on to the production floor. Robbins passed the tough Ford Q1 Quality Audit, and they are currently working to obtain ISO 9000 quality system certification. They are committed to continuous improvement of their processes, products and level of service.
Continuity Since 1943: Three generations of the Robbins family have owned and operated Robbins Auto Top Co. Their experience in the design, manufacturing and installation of convertible tops, glass and plastic windows, tonneau covers and related products is unmatched in the industry.
Using What They Manufacture: Robbins business began as a trim shop, and they continue to operate their own shop as an R & D center, where Robbins products are installed daily to check the fit and appearance. Not many other top manufacturers can say that. The advantages are many. We knew we had a problem with one of the Robbins MGB tops we carry, but it was intermittent and we could not pin it down. We finally arranged to have Robbins fit one of the problem tops on a customer’s car, they realized that the early 1963 folding top frame required a pattern of its own, so they made one. There are not many early ’63 MGBs running around, but they did it anyway.
6. Do I have to have the top professionally installed? Although good results may be achieved by non-professionals, best results are achieved by a professional with experience with MGB top installation. For this reason our tops do not come with installation instructions.