[C2] Installing Convertable top
Currently the doors and decklid are off the car. Do these need to be in place to install the top? It seems it is easier to work on the car with these not in the way.
Any tips from those who have done this are appreciated. Thanks!





JIM
I bought the Al Knoch installation CD . It suggested that you need to get the doors lined up first, adjust the frame and weather strip to the windows, and then install the top.
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Mark
As an installer the dilemma is; do I leave the top short (on the sides by the window) or stretch the snot out of it. Even when stretched it sometime doesn't fit the way I want it to. You are pretty far along into the install process when you realize it needs to be stretched.
As the previous poster said some of the tops are tight when fresh right out of the box.
The manufacture won't take the top back after the install is started and the customer doesn't want to hear about a short install. So, I would rather deal with a tight top then have to explain why the top doesn't fit all the way over the side rails.
A new top in the box will shrink over time. So, I would buy a fresh top form a reputable manufacture.
FYI, I don't have this issue with Stay-Fast material.
If it is not a numbers matching car I would always recommend a Stay-Fast top.
JMHO
Last edited by woodsdesign; Mar 7, 2017 at 08:07 AM.

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As long as you have the proper tools you can do the installation.
I agree, you must have the deck lid and doors on the car prior to installation. If you have a hardtop you install the hardtop first, adjust the door glass to fit the hardtop and then adjust your soft top frame to match the doors. If you don' have a hardtop then adjust the soft top (with weatherstripping installed) to fit the door glass for the best fit possible.
Willcox

Mark





After installing the deck lid, install the hard top. Then fit the side windows to the hard top. Remove the hard top and raise the soft top and then fit the soft top frame to the side windows. Use new tack strips and weatherstrips. Install the new soft top making sure it it still fits the side windows.
If the OP doesn't have a hard top:
Install the deck lid. After making sure the old top and frame fit the side windows, install the new soft top. Use new tack strips and weatherstrips.
Optional is to clean the top frame and repaint back to new looking.
Don
A Stayfast top is not a issue. I got one from Mike Coletta 2 years ago, and he had it a year or two. It'll be fine and is going on my own '59, along with a restored power top system....as soon as I find time.
Case 1- The 2 tops that gave me trouble were subjected to several years of heat cold cycle seasons in Long Island, New York, then came to me in Florida. One was actually 5 years old. Both shrank at the rear quarters and were difficult to stretch to the side window rear frames, and across the top on each side to the tops of the side windows. The new AK top was not a problem.
Case 2 - In 1986 I bought my '59. It was a 2 top car, with the hardtop on it. WHen I went to connect the top, it had shrunken considerably from being stored in the well.
Cases 3 to ??? - There are many examples of owners whose vinyl tops were stored in the wells for a long time. When they raised it, it wouldn't latch and fit properly. In the cases of C1 tops, many times the upper frame of the windshield would pull off of the top of the glass. I had that happen to mine 30 years ago.
The more a vinyl top is stored, the more it shrinks. Quite typical. Now if it's already installed, all you have to do is gradually let it heat soak in the sun and spray water on the inside. Gradually it will stretch and become pliable again.
In the case of a new installation, it takes considerable effort to manually stretch the vinyl to get proper fit. It can be done, but it makes a tedious job much more difficult.
I hope I've explained it within reason.
Edit. I often wondered why vinyl shrinks with age. Google just helped....From.....Here.
III. DIFFERENCES IN SHRINKAGE
What you should know
Both chemical and mechanical factors interplay to create shrinkage in vinyl. From a mechanical point of view, there must be some tension when winding up vinyl on rolls at the end of the calendar. A loosely wound roll would tend to telescope when moved. A tight wind helps to prevent the roll from flattening and reduces pressure marks during shipment and storage. Shrinkage caused by tension in wind up is called “snap back”. It usually occurs and is completed within a few hours after the vinyl is sheeted from the roll. A side effect of snap back is that as the vinyl shrinks in the calendaring direction, there is some slight increase in the width dimension. Attempts at introducing artificial shrinkage in low PHR vinyl by stretching at windup have not been successful.
A typical specification for mechanical shrinkage calls for not more than 1% change in dimension after 24 hours at room temperature.
After snap back is complete and as the vinyl ages, there will still be some residual shrinkage. Since flexible vinyl is a thermoplastic material, other stresses introduced in the manufacturing process will relax, causing the material to further condense over time. Another important consideration is the amount of plasticizer in the formulation. Softer vinyl tends to shrink more than firmer vinyl since their elasticity and elongation rates are higher. This brings us back to PHR of plasticizer differences in the formulations of two different vinyls that are being welded together. Normal bookbinding opaque vinyl with 33-35 PHR will tend to shrink more than a double polished clear vinyl with 25 PHR of plasticizer. Wrinkling occurs when two vinyls are welded together that have different rates of shrinkage. When one vinyl shrinks more than the other, the vinyl that shrinks less is displaced and this shows up as long undulating ridges of material. This “wrinkling” is exacerbated as the differences in the rates of shrinkage increase.
What you can do
Snap back can usually be handled in sheet fed work simply by giving the vinyl time to relax in low lifts after sheeting. Only a few hours is required to eliminate snap back problems. If roll feeding, dancer bars (accumulators) should be used to give the vinyl time to relax before reaching the welding die. Avoid introducing any tension in web feeding that could stretch the vinyl, especially when using softer materials.
With chemical shrinkage, since it is the nature of vinyl to shrink, heat sealers of two different materials should work with their suppliers to be sure that the vinyls that they are using have rates of shrinkage that are as close together as possible.
One highly respected bookbinder claims that he has minimized wrinkling by developing dies and heat-sealing techniques that weld the vinyl very tightly to the board and uses the board itself to staunch the vinyl from excessive shrinking.
As we have said before, when vinyl shrinks in the calendering direction, it can grow in the width. This sometimes causes a binder to look great coming off the heat sealer but “bag” a few days later. Vinyl sealed tight to the board will also minimize bagging.
Never cross grain materials when welding them together. Be sure that both pieces are taken from the roll in the same direction.
When packing heat-sealed products allow some space between the product and the top of the carton to absorb the weight of stacked cartons and not put pressure on the edges of the products.
Last edited by rich5962; Mar 7, 2017 at 09:51 PM.
Case 1- The 2 tops that gave me trouble were subjected to several years of heat cold cycle seasons in Long Island, New York, then came to me in Florida. One was actually 5 years old. Both shrank at the rear quarters and were difficult to stretch to the side window rear frames, and across the top on each side to the tops of the side windows. The new AK top was not a problem.
Case 2 - In 1986 I bought my '59. It was a 2 top car, with the hardtop on it. WHen I went to connect the top, it had shrunken considerably from being stored in the well.
Cases 3 to ??? - There are many examples of owners whose vinyl tops were stored in the wells for a long time. When they raised it, it wouldn't latch and fit properly. In the cases of C1 tops, many times the upper frame of the windshield would pull off of the top of the glass. I had that happen to mine 30 years ago.
The more a vinyl top is stored, the more it shrinks. Quite typical. Now if it's already installed, all you have to do is gradually let it heat soak in the sun and spray water on the inside. Gradually it will stretch and become pliable again.
In the case of a new installation, it takes considerable effort to manually stretch the vinyl to get proper fit. It can be done, but it makes a tedious job much more difficult.
I hope I've explained it within reason.
Edit. I often wondered why vinyl shrinks with age. Google just helped....From.....Here.
III. DIFFERENCES IN SHRINKAGE
What you should know
Both chemical and mechanical factors interplay to create shrinkage in vinyl. From a mechanical point of view, there must be some tension when winding up vinyl on rolls at the end of the calendar. A loosely wound roll would tend to telescope when moved. A tight wind helps to prevent the roll from flattening and reduces pressure marks during shipment and storage. Shrinkage caused by tension in wind up is called “snap back”. It usually occurs and is completed within a few hours after the vinyl is sheeted from the roll. A side effect of snap back is that as the vinyl shrinks in the calendaring direction, there is some slight increase in the width dimension. Attempts at introducing artificial shrinkage in low PHR vinyl by stretching at windup have not been successful.
A typical specification for mechanical shrinkage calls for not more than 1% change in dimension after 24 hours at room temperature.
After snap back is complete and as the vinyl ages, there will still be some residual shrinkage. Since flexible vinyl is a thermoplastic material, other stresses introduced in the manufacturing process will relax, causing the material to further condense over time. Another important consideration is the amount of plasticizer in the formulation. Softer vinyl tends to shrink more than firmer vinyl since their elasticity and elongation rates are higher. This brings us back to PHR of plasticizer differences in the formulations of two different vinyls that are being welded together. Normal bookbinding opaque vinyl with 33-35 PHR will tend to shrink more than a double polished clear vinyl with 25 PHR of plasticizer. Wrinkling occurs when two vinyls are welded together that have different rates of shrinkage. When one vinyl shrinks more than the other, the vinyl that shrinks less is displaced and this shows up as long undulating ridges of material. This “wrinkling” is exacerbated as the differences in the rates of shrinkage increase.
What you can do
Snap back can usually be handled in sheet fed work simply by giving the vinyl time to relax in low lifts after sheeting. Only a few hours is required to eliminate snap back problems. If roll feeding, dancer bars (accumulators) should be used to give the vinyl time to relax before reaching the welding die. Avoid introducing any tension in web feeding that could stretch the vinyl, especially when using softer materials.
With chemical shrinkage, since it is the nature of vinyl to shrink, heat sealers of two different materials should work with their suppliers to be sure that the vinyls that they are using have rates of shrinkage that are as close together as possible.
One highly respected bookbinder claims that he has minimized wrinkling by developing dies and heat-sealing techniques that weld the vinyl very tightly to the board and uses the board itself to staunch the vinyl from excessive shrinking.
As we have said before, when vinyl shrinks in the calendering direction, it can grow in the width. This sometimes causes a binder to look great coming off the heat sealer but “bag” a few days later. Vinyl sealed tight to the board will also minimize bagging.
Never cross grain materials when welding them together. Be sure that both pieces are taken from the roll in the same direction.
When packing heat-sealed products allow some space between the product and the top of the carton to absorb the weight of stacked cartons and not put pressure on the edges of the products.
Thanks for your detailed response. Do you have any idea what time period to discard the top in the box for a new top?
Rick










Dennis






