I chopped my first roof when I was 17 in the early 70′s and made a real mess of it. This first attempt taught me a lot and when it was time to chop my second top I knew how to avoid the problems I had with my first attempt. The second top came out just as I wanted it to be and I have been cutting roofs ever since. I picked a car with curved screens for my first chops and the glass part of the project was extremely frustrating and will be explained further soon. So I stayed with cars with flat glass windshields for a while until I got a better understanding on the degree of difficulty when it came to cutting curved windshields.
Not knowing how to cut the curved windshield glass I had to find a glass cutter who could cut down the windshield to suit my new roof and windshield opening. I was lucky enough to find such a talented person who taught me a lot about glass and cutting it. This made chopping curved windshield top a lot more comfortable and easier, but still not as easy as cars with flat glass. Even with his years of experience there were breakages, and much swearing and the additional costs for lost windshields etc. After a while he asked me why I needed to chop cars and why I was not having my glass custom made? He referred me to a local manufacturer that explained what they needed to make me new glass that fitted my needs. And since then I have used this process so many times to supply windshields to my customers for their chopped customs and the availability of an additional replacements in the chance of breakage at the cost of a comparable standard automotive windshield. And allows for other owners of the same make of car to have a chop performed with the knowledge of an available screen at a set price.
Over the last 30 odd years I have shared this knowledge and my method of making screen masters and manufacturers with other customizers to make this part of a chop just a little easier and less stressful.
It is not too hard to do, just takes some time to get it perfect, just like all the rest on your project car. And there is a cost involved, initially many people are hesitant believing that there should be no problem just getting a screen cut. And in many cases that is the way it happens, but in others its just a disappointing episode of broken screens. Even the best cutters have bad runs for no explainable reason.
Below are a series of photos I took during the process which I hope will explain the process. Hopefully it will inspire some to create custom made windshield for their project cars.
The windshield opening for the 1948 Hudson that we made was custom shaped to fit the rest of the car in the best possible way. I knew the glass was going to be custom made, so I could create the opening shape I wanted, full creative freedom.
Starting with a piece of thin laminated timber it was trimmed and clamped in place till it fitted the new opening. This process can be time consuming, but you do not want to rush this.
The curved timber pattern was then laminated with Fiberglass to form a rigid pattern that could be fine tuned to fit the opening perfectly. Not pictured here is the Bracing at the back of the pattern. This is used to make sure nothing moves or changes while the furnace mould is being made.
Allowances must be made for rubber or other fitting methods and all gaps and clearances must be exact, again take your time here.
More gaping with all moldings in place.
The fiberglass pattern is then supplied to the glass manufacturer for the fabrication of a furnace mould that will be used in the production of the finished screen.
Just delivered, and sat in place to see how it looks!
At this stage the new screen is trial fitted in the opening with all brightwork in place to check all clearances. If there are any parts that are not 100% the glass manufacturer can make adjustments to the furnace mould and produce another screen. Better to get it sorted at this part of the build.
Here are a few more photo from a different project I did. These show the bracing on the back of the pattern.